INTERNET-DRAFT
                                                                       R. deBry
                                                                IBM Corporation
                                                                    T. Hastings
                                                              Xerox Corporation
                                                                     R. Herriot
                                                               Sun Microsystems
                                                                    S. Isaacson
                                                                   Novell, Inc.
                                                                      P. Powell
                                                     San Diego State University
                                                                  June 23, 1997
       
                 Internet Printing Protocol/1.0: Model and Semantics
                             draft-ietf-ipp-model-02.txt
       
       Status of this Memo
       
       This document is an Internet-Draft.  Internet-Drafts are working
       documents of the Internet Engineering Task Force (IETF), its areas, and
       its working groups.  Note that other groups may also distribute working
       documents as Internet-Drafts.
       
       Internet-Drafts are draft documents valid for a maximum of six months
       and may be updated, replaced, or obsoleted by other documents at any
       time.  It is inappropriate to use Internet-Drafts as reference material
       or to cite them other than as "work in progress".
       
       To learn the current status of any Internet-Draft, please check the
       "1id-abstracts.txt" listing contained in the Internet-Drafts Shadow
       Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe),
       munnari.oz.au (Pacific Rim), ds.internic.net (US East Coast), or
       ftp.isi.edu (US West Coast).
       
       Abstract
       
       This document is one of a set of documents, which together describe all
       aspects of a new Internet Printing Protocol (IPP).  IPP is an
       application level protocol that can be used for distributed printing
       using Internet tools and technology.  The protocol is heavily influenced
       by the printing model introduced in the Document Printing Application
       (ISO/IEC 10175 DPA) standard.  Although DPA specifies both end user and
       administrative features, IPP version 1.0 is focused only on end user
       functionality.
       
       The full set of IPP documents includes:
       
       
       
       
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         Internet Printing Protocol: Requirements
         Internet Printing Protocol/1.0: Model and Semantics
         Internet Printing Protocol/1.0: Security
         Internet Printing Protocol/1.0: Protocol Specification
         Internet Printing Protocol/1.0: Directory Schema
       
       The requirements document takes a broad look at distributed printing
       functionality, and it enumerates real-life scenarios that help to
       clarify the features that need to be included in a printing protocol for
       the Internet.  It identifies requirements for three types of users: end
       users, operators, and administrators.  The requirements document calls
       out a subset of end user requirements that MUST be satisfied in the
       first version of IPP.  Operator and administrator requirements are out
       of scope for v1.0. The model and semantics document describes a
       simplified model with abstract objects, their attributes, and their
       operations. The model introduces a Printer object and a Job object.  The
       Job object supports multiple documents per job.  The security document
       covers potential threats and proposed counters to those threats.  The
       protocol specification is formal document which incorporates the ideas
       in all the other documents into a concrete mapping using clearly defined
       data representations and transport protocol mappings that real
       implementers can use to develop interoperable client and server side
       components. Finally, the directory schema document shows a generic
       schema for directory service entries that represent instances of IPP
       Printers.
       
       This document is the "Internet Printing Protocol/1.0: Model and
       Semantics" document.
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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                                  Table of Contents
       
       1. Introduction.......................................................7
       2. Terminology........................................................7
          2.1  Conformance Terminology ......................................8
             2.1.1 MUST......................................................8
             2.1.2 MUST NOT..................................................8
             2.1.3 SHOULD....................................................8
             2.1.4 SHOULD NOT................................................8
             2.1.5 MAY.......................................................8
             2.1.6 CONDITIONALLY MANDATORY...................................9
             2.1.7 NEED NOT..................................................9
          2.2  Model Terminology ...........................................10
             2.2.1 Keyword..................................................10
             2.2.2 Parameters...............................................10
                2.2.2.1  Parameter Name ....................................10
                2.2.2.2  Parameter Value ...................................10
                2.2.2.3  Parameter Syntax ..................................10
             2.2.3 Attributes...............................................11
                2.2.3.1  Attribute Name ....................................11
                2.2.3.2  Attribute Group Name ..............................11
                2.2.3.3  Attribute Value ...................................11
                2.2.3.4  Attribute Syntax ..................................11
             2.2.4 Supports.................................................12
       3. Simplified Printing Model.........................................12
       4. IPP Objects.......................................................15
          4.1  Printer Object ..............................................15
          4.2  Job Object ..................................................17
          4.3  Document Object .............................................18
          4.4  Object Relationships ........................................19
          4.5  Object Attributes ...........................................19
             4.5.1 Job Template Attribute Overview..........................19
             4.5.2 The "best-effort" Job Attribute Overview.................20
          4.6  Object Identity .............................................20
       5. IPP Operations....................................................21
          5.1  Operation Semantics .........................................22
             5.1.1 Get-Operations Operation.................................22
                5.1.1.1  Get-Operations Request ............................23
                5.1.1.2  Get-Operations Response ...........................23
             5.1.2 Print-Job Operation......................................23
                5.1.2.1  Print-Job Request .................................23
                5.1.2.2  Print-Job Response ................................25
             5.1.3 Print-URI Operation......................................26
                5.1.3.1  Print-URI Request .................................26
                5.1.3.2  Print-URI Response ................................26
             5.1.4 Validate-Job Operation...................................27
                5.1.4.1  Validate-Job Request ..............................27
                5.1.4.2  Validate-Job Response .............................27
       
       
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             5.1.5 Create-Job Operation.....................................28
                5.1.5.1  Create-Job Request ................................28
                5.1.5.2  Create Job Response ...............................28
             5.1.6 Send-Document Operation..................................29
                5.1.6.1  Send-Document Request .............................29
                5.1.6.2  Send-Document Response ............................29
             5.1.7 Send-URI Operation.......................................30
                5.1.7.1  Send-URI Request ..................................30
                5.1.7.2  Send-URI Response .................................30
             5.1.8 Cancel Job Operation.....................................30
                5.1.8.1  Cancel-Job Request ................................31
                5.1.8.2  Cancel-Job Response ...............................31
             5.1.9 Get-Attributes Operation.................................31
                5.1.9.1  Get-Attributes Request ............................31
                5.1.9.2  Get-Attributes Response ...........................33
             5.1.10 Get-Jobs Operation .....................................34
                5.1.10.1 Get-Jobs Request ..................................34
                5.1.10.2 Get-Jobs Response .................................34
          5.2  Operation Status Codes and Messages .........................35
       6. Object Attributes.................................................35
          6.1  Attribute Syntaxes ..........................................36
             6.1.1 Attribute Extensibility..................................37
          6.2  Job Template Attributes .....................................38
             6.2.1 job-name (name)..........................................42
             6.2.2 job-sheets (type4 keyword)...............................43
             6.2.3 notify-events (1setOf type2 keyword).....................43
             6.2.4 notify-addresses (1setOf uri)............................43
             6.2.5 job-priority (integer(1:100))............................44
             6.2.6 job-hold-until (type4 keyword)...........................44
             6.2.7 multiple-documents-are (type2 keyword)...................45
             6.2.8 best-effort (type2 keyword)..............................45
             6.2.9 media (type4 keyword)....................................47
             6.2.10 number-up (type3 keyword) ..............................47
             6.2.11 sides (type2 keyword) ..................................48
             6.2.12 printer-resolution (type2 keyword) .....................48
             6.2.13 print-quality (type2 keyword) ..........................49
             6.2.14 copies (integer(1:2**31 - 1)) ..........................49
             6.2.15 finishing (1setOf type2 keyword) .......................49
             6.2.16 document-format (type2 keyword) ........................50
             6.2.17 compression (type3 keyword) ............................50
             6.2.18 job-k-octets (integer(0:2**31 - 1)) ....................50
             6.2.19 job-impressions (integer(0:2**31 - 1)) .................50
             6.2.20 job- media-sheets (integer(0:2**31 - 1)) ...............51
          6.3  Job Description Attributes ..................................51
             6.3.1 job-uri (uri)............................................52
             6.3.2 job-uri-user (uri).......................................53
             6.3.3 job-originating-user (name)..............................53
             6.3.4 job-originating-host (name)..............................53
       
       
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             6.3.5 user-locale (type3 keyword)..............................53
             6.3.6 job-state (type1 keyword)................................53
             6.3.7 job-state-reasons (1setOf  type2 keyword)................53
             6.3.8 job-state-message (text).................................53
             6.3.9 output-device-assigned (name)............................53
             6.3.10 time-since-pending (milliseconds) ......................54
             6.3.11 time-since-processing (milliseconds) ...................54
             6.3.12 time-since-completed (milliseconds) ....................54
             6.3.13 number-of-intervening-jobs (integer(0:2**31 - 1)) ......54
             6.3.14 job-message-from-operator (text) .......................54
             6.3.15 job-k-octets-completed (integer(0:2**31 - 1)) ..........54
             6.3.16 job-impressions-completed  (integer(0:2**31 - 1)) ......55
             6.3.17 job-media-sheets-completed (integer(0:2**31 - 1)) ......55
          6.4  Document Attributes .........................................55
             6.4.1 document-name (name).....................................55
             6.4.2 document-format (type2 keyword)..........................55
             6.4.3 document-uri (uri).......................................56
          6.5  Printer Description Attributes ..............................56
             6.5.1 printer-uri (uri)........................................57
             6.5.2 printer-uri-user (uri)...................................58
             6.5.3 printer-name (name)......................................58
             6.5.4 printer-location (text)..................................58
             6.5.5 printer-description (text)...............................58
             6.5.6 printer-more-info-site (uri).............................58
             6.5.7 printer-driver-installer (uri)...........................58
             6.5.8 printer-make-and-model (text)............................58
             6.5.9 printer-more-info-manufacturer (uri).....................59
             6.5.10 printer-state (type1 keyword) ..........................59
             6.5.11 printer-state-reasons (1setOf type2 keyword) ...........60
             6.5.12 printer-is-accepting-jobs (boolean) ....................62
             6.5.13 printer-state-message (text) ...........................62
             6.5.14 queued-job-count (integer(0:2**31 - 1)) ................62
             6.5.15 printer-message-from-the-operator (text) ...............62
             6.5.16 printer-locale (locale) ................................62
             6.5.17 printer-locales-supported (1setOf locale) ..............62
             6.5.18 color-supported (boolean) ..............................62
       7. Conformance.......................................................63
          7.1  Conditionally Mandatory .....................................63
          7.2  Client Conformance Requirements .............................63
          7.3  Printer Object Conformance Requirements .....................63
             7.3.1 Objects..................................................64
             7.3.2 Operations...............................................64
             7.3.3 Attributes...............................................64
             7.3.4 Printer extensions.......................................65
             7.3.5 Attribute Syntaxes.......................................65
          7.4  Security Conformance Requirements ...........................65
       8. IANA Considerations, Registered Extensions, Private Extensions....66
       9. Security Considerations...........................................66
       
       
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       10.References .......................................................66
       11.Author's Address .................................................67
       12.APPENDIX A - Status Codes ........................................70
          12.1 Status Codes (type2 keyword) ................................70
             12.1.1 Informational ..........................................71
             12.1.2 Successful Status Codes ................................71
                12.1.2.1 successful-OK (IPPL1) .............................71
             12.1.3 Redirection Status Codes ...............................71
             12.1.4 Client Error Status Codes ..............................71
                12.1.4.1 client-error-bad-request (IPPL1) ..................71
                12.1.4.2 client-error-unauthorized .........................71
                12.1.4.3 client-error-payment-required .....................72
                12.1.4.4 client-error-forbidden (IPPL1) ....................72
                12.1.4.5 client-error-method-not-allowed ...................72
                12.1.4.6 client-error-timeout (NEW) ........................72
                12.1.4.7 client-error-not-found ............................72
                12.1.4.8 client-error-gone .................................72
                12.1.4.9 client-error-request-entity-too-large (IPPL1) .....73
                12.1.4.10client-error-request-URI-too-long .................73
                12.1.4.11client-error-unsupported-media-type (IPPL1) .......73
                12.1.4.12client-error-attribute-value-not-supported ........73
             12.1.5 Server Error Status Codes ..............................74
                12.1.5.1 server-error-internal-server-error ................74
                12.1.5.2 server-error-operation-not-implemented ............74
                12.1.5.3 server-error-service-unavailable ..................74
                12.1.5.4 server-error-timeout (NEW) ........................74
                12.1.5.5 server-error-HTTP-version-not-supported (NEW) .....74
                12.1.5.6 server-error-IPP-version-not-supported ............75
                12.1.5.7 server-error-printer-error ........................75
                12.1.5.8 server-error-write-fault ..........................75
          12.2 Mapping of HTTP 1.1 Status Codes to IPP Status Keywords .....76
          12.3 Status Keywords for IPP Operations ..........................77
       13.APPENDIX B - "document-format" Values ............................77
       14.APPENDIX C - "media" Values ......................................80
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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       1. Introduction
       
       The Internet Printing Protocol (IPP) is an application level protocol
       that can be used for distributed printing on the Internet.  The protocol
       is heavily influenced by the printing model introduced in the Document
       Printing Application (ISO/IEC 10175 DPA) standard.  Although DPA
       identifies both end user and administrative features, the first version
       of IPP is focused only on end user functionality.
       
       Section 2 introduces the terminology used within this document.
       
       Section 3 introduces the simplified IPP model.  The IPP model is made
       simple by exposing only the objects, attributes, and operations that are
       essential for end user access and control of the print system.  When
       future versions of IPP include features which satisfy operator and
       administrator requirements, the model can be extended to support the
       appropriate objects, attributes, and operations.
       
       Section 4 introduces the full semantics of the Printer, Job, and
       Document objects in the IPP model.  It covers how instances of these
       objects are identified, named, and related to each other.
       
       Section 5 covers the operations that are part of the IPP model.  These
       operations include: the Create-Job, Send-Document, Print-Job, Cancel,
       Get-Attributes, and Get-Jobs operations.
       
       Section 6 describes the attributes, their syntaxes, and semantics which
       are part of the IPP model.  Each object's attributes are described, and
       the attributes are grouped into logical groups to help clarify their
       relationships and meaning.  These groups are also used to simplify
       queries that request multiple attributes.
       
       Section 7 is a review of conformance issues and clarifies requirements
       that apply to client side and server side implementations.
       
       Sections 8-11 cover extensibility, security, technical references, and
       author information.
       
       
       2. Terminology
       
       This specification uses the terminology defined in this section.
       
       
       
       
       
       
       
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       2.1 Conformance Terminology
       
       The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
       "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and  "OPTIONAL" in this
       document are to be interpreted as described in RFC 2119 [25].
       
       2.1.1 MUST
       
       This word, or the terms "REQUIRED",  "SHALL" or "MANDATORY", mean that
       the definition is an absolute requirement of the specification.
       
       ISSUE: There are too many "SHALLs" in the document right now.  Carl-Uno
       makes the comment: "I think we have gone overboard in the use of SHALL
       in this version.  Every time we need a verb it is preceded by a SHALL,
       also in places where it does not serve any purpose.  I think that this
       only detracts from the places where SHALL is really useful."  These do
       need to be cleaned up.    Also, many of our conformance requirements in
       the form of MANDATORY, CONDITIONALLY MANDATORY and SHALL statements are
       too stringent, and needs quite a bit of relaxation.
       
       2.1.2 MUST NOT
       
       This phrase, or the phrase "SHALL NOT", mean that the definition is an
       absolute prohibition of the specification.
       
       2.1.3 SHOULD
       
       This word, or the adjective "RECOMMENDED", mean that there may exist
       valid reasons in particular circumstances to ignore a particular item,
       but the full implications must be understood and carefully weighed
       before choosing a different course.
       
       2.1.4 SHOULD NOT
       
       This phrase, or the phrase "NOT RECOMMENDED" mean that there may exist
       valid reasons in particular circumstances when the particular behavior
       is acceptable or even useful, but the full implications should be
       understood and the case carefully weighed before implementing any
       behavior described with this label.
       
       2.1.5 MAY
       
       This word, or the adjective "OPTIONAL", mean that an item is truly
       optional.  One vendor may choose to include the item because a
       particular marketplace requires it or because the vendor feels that it
       enhances the product while another vendor may omit the same item.   An
       implementation which does not include a particular option MUST be
       prepared to interoperate with another implementation which does include
       
       
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       the option, though perhaps with reduced functionality. In the same vein
       an implementation which does include a particular option MUST be
       prepared to interoperate with another implementation which does not
       include the option (except, of course, for the feature the option
       provides.)
       
       2.1.6 CONDITIONALLY MANDATORY
       
       This term means that an item MUST be implemented in a conforming
       implementation if the item corresponds to a feature or behavior that the
       implementation is capable of realizing.  It is also true, that a
       conforming implementation is not required to implement the items that
       correspond to features or behaviors that the implementation is not
       capable of realizing.
       
       ISSUE:  Should we use the following definition and define an explicit
       condition for each attribute labeled as CONDITIONALLY MANDATORY?
       
         This term means that an item MUST be implemented in a conforming
            implementation if the specified condition is true.  Furthermore, a
            conforming implementation NEED NOT implement the item if the
            specified condition is false.
       
       2.1.7 NEED NOT
       
       The verb "NEED NOT" indicates an action that the subject of the sentence
       does not have to implement in order to claim conformance to the
       standard.  The verb "NEED NOT" is used instead of "MAY NOT" since "MAY
       NOT" sounds like a prohibition.
       
       ISSUE:  Occasionally in the document the terms MANDATORY and OPTIONAL
       get used for what a requester shall supply in a request or what a
       provider shall return in a response.  I think that it is confusing to
       say that such and such input parameter is OPTIONAL meaning that the
       requester NEED NOT supply it in a request because it sounds like we are
       saying that the requester NEED not implement the input parameter and
       that the provide need not support the input parameter.  Same for
       responses.  Instead of labeling input parameters and output parameters
       as MANDATORY and OPTIONAL, just say something like "the requester SHALL
       supply the xxx input-parameter in the yyy operation"  or "the requester
       MAY supply the zzz input-parameter in the yyy operation" or "the
       requester NEED NOT supply the zzz input-parameter in the yyy operation".
       In headings for parameters, how about: "(SHALL be supplied)" and "(MAY
       be omitted)"?  In the description of each parameter we need to also
       specify whether support of the input parameter is MANDATORY for the
       provider or whether support is OPTIONAL.
       
       
       
       
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       2.2 Model Terminology
       
       2.2.1 Keyword
       
       Keywords are used within this document as identifiers of semantic
       entities within the abstract model.  Attribute names, attribute values,
       attribute syntaxes, and attribute groups are represented as keywords. In
       this document, a keyword is a sequence of characters (length of 1 to
       255) which consists of the following ASCII characters: lower-case
       letters, digits, hyphen ("-"), and underscore ("_").  A keyword MUST
       start with a lower-case letter.  In the actual protocol, these keywords
       will be represented using an appropriate protocol encoding (strings,
       enumerated values, constants, operation codes, identifiers, etc.).
       
       2.2.2 Parameters
       
       A parameter is an item of information supplied in an operation
       consisting of a parameter name and parameter value(s) using a specific
       syntax for that parameter.  Clients supply input parameters in an
       operation request and Printers return output parameters in an operation
       response.  Most parameters have corresponding object attributes, some do
       not.  All parameters are defined in section 5.  Parameterare identified
       as being "MANDATORY", "CONDITIONALLY MANDATORY", or "OPTIONAL" for
       implementation and "SHALL be supplied" or "MAY be omitted" in operation
       requests and responses.
       
       2.2.2.1 Parameter Name
       
       Each parameter is uniquely identified in this document by its parameter
       name which is a keyword.  The keyword parameter name is given in the
       section header describing that parameter.  In running text in this
       document, parameter names are indicated inside double quotation marks
       (").
       
       2.2.2.2 Parameter Value
       
       Each parameter has one or more values.  Parameter values are represented
       in the syntax type specified for that parameter. In running text in this
       document, parameter values are indicated inside single quotation marks
       ('), whether their parameter syntax is keyword, integer, text, etc.
       
       2.2.2.3 Parameter Syntax
       
       Each parameter is defined using an explicit syntax.  In this document,
       each syntax type is defined as a keyword with specific meaning.  The
       protocol specification document [23] indicates the actual representation
       for each parameter syntax that SHALL be used for the actual protocol.
       
       
       
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       Parameter syntaxes are the same as attribute syntaxes which are defined
       in section 6.1.
       
       2.2.3 Attributes
       
       An attribute is an item of information that is associated with an object
       instance consisting of an attribute name and attribute value(s) using a
       specific syntax for that attribute. A requester sets an attribute by
       supplying an input parameter in an operation request which has the same
       syntax as the attribute.  A provider returns an attribute by supplying
       an output parameter in an operation response which has the same syntax
       as the attribute.  The attributes that can be set by a client have a
       corresponding representation as an input parameter.  The attributes that
       can be queires by a client have a corresonding representation as an
       output parameter.   All attributes are defined in section 6.  Attributes
       are identified as being "MANDATORY", "CONDITIONALLY MANDATORY", or
       "OPTIONAL".
       
       2.2.3.1 Attribute Name
       
       Each attribute is uniquely identified in this document by its attribute
       name which is a keyword.  The keyword attribute name is given in the
       section header describing that attribute.  In running text in this
       document, attribute names are indicated inside double quotation marks
       (").
       
       2.2.3.2 Attribute Group Name
       
       Related attributes are grouped into named attribute groups.  The name of
       the group is a keyword.  It MAY be used as the value of an input
       parameter in place of naming all the attributes in the group explicitly.
       Attribute groups are defined in section 6.
       
       2.2.3.3 Attribute Value
       
       Each attribute has one or more values.  Attribute values are represented
       in the syntax type specified for that attribute. In running text in this
       document, attribute values are indicated inside single quotation marks
       ('), whether their attribute syntax is keyword, integer, text, etc.
       
       2.2.3.4 Attribute Syntax
       
       Each attribute is defined using an explicit attribute syntax.  In this
       document, each attribute syntax is defined as a keyword with specific
       meaning.  The protocol specification document [23] indicates the actual
       representation for each attribute syntax that SHALL be used for the
       actual protocol.  Attribute syntaxes are defined in section 6.1.
       
       
       
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       2.2.4 Supports
       
       By definition, a job processing behavior or selectable feature is
       supported by a Printer only if that Printer responds with the
       corresponding attribute and the associated value in a response to a
       query for that attribute. A given implementation may exhibit a behavior
       that corresponds to the value of some supported attribute, but if the
       implementation, when queried for that attribute, doesn't respond with
       the supported attribute populated with that specific value, then as far
       as IPP is concerned, that Printer does not support that feature. A
       conforming implementation SHALL support all MANDATORY attributes and all
       CONDITIONALLY MANDATORY attributes whose possible values correspond to
       the behaviors that the implementation is capable of realizing. Therefore
       conformance to IPP does not mandate that all implementations support all
       possible values representing all possible job processing behaviors and
       features.
       
       For example, if a given instance of a Printer supports only certain
       document formats, then that Printer SHALL respond with the "document-
       format-supported" attribute populated with a set of values, possibly
       only one, taken from the entire set of possible values defined in this
       model document.  This set of values represent the Printer's set of
       supported document formats.  Another example is the "finishings-
       supported" attribute.  If a Printer is not physically capable of
       stapling (there is no stapler in the output device itself), the
       "finishings-supported" attribute MUST NOT be populated with the value of
       'staple'.
       
       Note: The supported attributes are set (populated) by some
       administrative process or automatic sensing mechanism which is outside
       the scope of IPP.
       
       
       3. Simplified Printing Model
       
       In order to a achieve its goal of realizing a workable printing protocol
       for the Internet, IPP is based on a simplified printing model which
       abstracts the many (often complex) components of real world printing
       solutions.  Many of these systems include features, interfaces, and
       relationships that are beyond the scope of IPP.  IPP has to run in a
       distributed computing environment where requesters of print services
       (clients, applications, PC drivers, etc.) cooperate and interact with
       print service providers.  Although the underlying configuration may be a
       complex n-tier client/server system, an important simplifying step in
       the IPP model is to expose only the key objects and interfaces required
       for printing.  The IPP model encapsulates these important elements into
       three simple objects:
       
       
       
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         Printer (Section 4.1)
         Job (Section 4.2)
         Document (Section 4.3)
       
       Each of these objects has a set of operations associated with it.  These
       include:
       
         Printer:
            Get-Operations (Section 5.1.1)
            Print-Job (Section 5.1.2)
            Print-URI (Section 5.1.3)
            Validate-Job (Section 5.1.4)
            Create-Job (Section 5.1.5)
            Get-Attributes (Section 5.1.9)
            Get-Jobs (Section 5.1.10)
         Job
            Send-Document(Section 5.1.6)
            Send-URI (Section 5.1.7)
            Cancel-Job (Section 5.1.8)
            Get-Attributes (Section 5.1.9)
       
       There are no operations defined for a Document object.  All document
       information is accessed through a Job object and its operations.
       
       It is important, however, to understand that in real system
       implementations (which lie underneath the abstracted IPP model), there
       are other components of a print service which are not explicitly defined
       in the IPP model. The following figure illustrates where IPP fits with
       respect to these other components.
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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                                    +--------------+
                                    |  Application |
                          o         +. . . . . . . |
                         \|/        |   Spooler    |
                         / \        +. . . . . . . |   +---------+
                       End-User     | Print Driver |---|  File   |
             +-----------+ +-----+  +------+-------+   +----+----+
             |  Browser  | | GUI |         |                |
             +-----+-----+ +--+--+         |                |
                   |          |            |                |
                   |      +---+------------+---+            |
       N   D   S   |      |      IPP Client    |------------+
       O   I   E   |      +---------+----------+
       T   R   C   |                |
       I   E   U   |
       F   C   R   -------------- Transport ------------------
       I   T   I
       C   O   T                    |         --+
       A   R   Y           +--------+--------+  |
       T   Y               |    IPP Server   |  |
       I                   +--------+--------+  |
       O                            |           |
       N                   +-----------------+  | IPP Printer
                           |  Print Service  |  |
                           +-----------------+  |
                                    |         --+
                           +-----------------+
                           | Output Device(s)|
                           +-----------------+
       
       IPP Printers encapsulate the functions normally associated with physical
       output devices along with the spooling, scheduling and multiple device
       management functions associated with a print server. Printers may be
       registered as entries in a directory where end users find and select
       them based on some sort of filtered and context based searching.  The
       directory is used to store relatively static information about the
       Printer, allowing end users to search for and find Printers that match
       their search criteria (name, context, printer capabilities, etc.).
       
       IPP clients implement the IPP protocol on the client side and give end
       users or programs the ability to query an IPP Printer and submit and
       manage their print jobs.  An IPP server is just that part of the IPP
       Printer that implements the protocol.  The rest of the IPP Printer
       implements the application semantics of the print service itself.  The
       IPP Printer MAY be embedded in an output device or MAY be embedded in a
       host on the network that communicates with the output device.  All
       information about the Printer, both static and dynamic information, can
       
       
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       be accessed directly from the Printer itself.  The more dynamic
       information associated with a Printer includes state, currently loaded
       and ready media, number of jobs on the Printer, errors, warnings, etc.
       When a job is submitted to the Printer, the Printer SHALL create a Job
       object.  The end user then interacts with this new Job to query its
       status and monitor the progress of the job.  End users may also cancel
       the Job.  The end user is able to register to receive certain events
       which are then routed using the notification service(s).
       
       
       4. IPP Objects
       
       An IPP object is defined as set of attributes that can be potentially
       supported by each instance of the object.  The attributes for each
       object type are identified as MANDATORY, CONDITIONALLY MANDATORY, or
       OPTIONAL (see section 2).  Each instance of an IPP object supports an
       appropriate set of attributes (with values for each of the attributes)
       that describe that instance.  That is, an IPP Printer object is defined
       as set of attributes that can potentially be implemented by some entity
       claiming to be an IPP Printer.  In the same manner, a Job object is
       defined as a set of attributes that are potentially associated with each
       instance of a Job object.
       
       4.1 Printer Object
       
       A major component of the IPP model is the Printer object.The
       capabilities and state of an IPP Printer are described by its
       attributes.  Printer attributes are grouped as follows:
       
         "job-template" attributes (section 6.2)
         "printer-description" attributes (section 6.5)
       
       Operations which are invoked on a printer include:
       
         Get-Operations (Section 5.1.1)
         Print-Job (section 5.1.2)
         Print-URI (Section 5.1.3)
         Validate-Job (Section 5.1.4)
         Create-Job (section 5.1.5)
         Get-Attributes (section 5.1.9)
         Get-Jobs (section 5.1.10)
       
       An instance of a Printer object implements IPP.  Using the protocol, end
       users may query the attributes of the Printer, submit jobs to the
       Printer, determine subsequent states of submitted and queued jobs, and
       cancel their own print jobs. The realization of a Printer object may
       take on different forms for any given configuration of real components.
       
       
       
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       However, the details of the configuration of real components are
       transparent to the end user.
       
       Since a Printer object is an abstraction of a generic document output
       device or print service provider, an IPP Printer object could be used to
       represent any real or virtual device with semantics consistent with the
       Printer object. For example, an instance of a Printer object could be
       used to front end a fax-out device, any kind of imager, or even a CD
       writer.
       
       Some examples of configurations supporting a Printer object include:
       
         1) An output device, with no spooling capabilities
         2) An output device, with a built-in spooler
         3) A print server supporting IPP with one or more associated output
            devices
            3a) The associated output devices might or might not be capable of
              spooling jobs
            3b) The associated output devices might or might not support IPP
       
       See the following figures for some examples on how to view Printer
       objects on top of several print system configurations.  The embedded
       case below represents configurations 1 and 2. The hosted and fan-out
       figures below represent configuration 3.
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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       Legend:
       
       ##### indicates a Printer object which is
             either embedded in an output device or is
             hosted in a server.  The implementation
             might or might not be capable of queuing/spooling.
       
       any   indicates any network protocol or direct
             connect, including IPP
       
       
       embedded printer:
                                                 output device
                                               +---------------+
        O   +--------+                         |  ###########  |
       /|\  | client |------------IPP------------># Printer #  |
       / \  +--------+                         |  # Object  #  |
                                               |  ###########  |
                                               +---------------+
       
       
       hosted printer:
                                               +---------------+
        O   +--------+        ###########      |               |
       /|\  | client |--IPP--># Printer #-any->| output device |
       / \  +--------+        # Object  #      |               |
                              ###########      +---------------+
       
       
       
                                                +---------------+
       fan out:                                 |               |
                                            +-->| output device |
                                        any/    |               |
        O   +--------+      ###########   /     +---------------+
       /|\  | client |-IPP-># Printer #--*
       / \  +--------+      # Object  #   \     +---------------+
                            ########### any\    |               |
                                            +-->| output device |
                                                |               |
                                                +---------------+
       
       
       
       4.2 Job Object
       
       A Job object is used to model a job.  A job can contain one or more
       documents.  The information required to create a Job object is sent in a
       
       
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       create request from the end user via an IPP client to a Printer.  A
       create request can be either a Print-Job Request, a Print-URI request,
       or a Create-Job Request.  The Printer MUST perform validation checks to
       verify that the job may indeed be processed.  A client MAY send a
       Validate-Job Request (with no document data) so that the Printer
       performs all validation checks without the overhead of transferring all
       of the document data.  As an example of some of the validation checks
       that are performed, the create request may specify that the documents
       within the job are to be printed duplex (on both sides of the media).
       However, the Printer might not support such a feature.  Once the Printer
       validates the submitted information, a Job object is created.  The
       instance of the Job object is initialized with information from the
       create request.  If a Create-Job operation is used to create the Job
       object, subsequent Send-Document operations are used to transfer the
       document data from the client to the IPP Printer.
       
       This model specification defines rules for what MUST be done when:
       
         - optional attributes are missing
         - there are conflicts between what is supported and what is requested
         - there are conflicts between what the client requests via external
            attributes in the IPP operation and what the client requests in
            embedded instructions in the document page description language
            (PDL).
       
       Job attributes are grouped as follows:
       
         "job-template" attributes (optionally supplied by the client/end
            user, section 6.2)
         "job-description" attributes (set by the Printer, section 6.3)
       
       The following operations can be invoked on Jobs:
       
         Send-Document (section 5.1.6)
         Send-URI (Section 5.1.7)Cancel Job (section 5.1.8)
         Get-Attributes (section 5.1.9)
       
       
       4.3 Document Object
       
       A Document object consists of printable data and Document Attributes
       (see section 6.4).  These Document Attributes only describe the data to
       be printed; they do not include any specialized document processing
       instructions that apply to only one Document in a multi-document Job.
       All Job Template attributes (those attributes that describe desired job
       processing behavior) are defined as part of the Job object, therefore,
       they apply equally to all Documents within a Job. Currently there are no
       operations defined for Document objects.
       
       
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       4.4 Object Relationships
       
       Instances of objects within the system have relationships that MUST be
       maintained persistently along with the persistent storage of the object
       attributes.  A Printer can represent one or more output devices.  An
       output device can be represented by at most one Printer object.  A
       Printer can contain zero or more Job objects.  A Job object is contained
       in exactly one Printer object.  A Job object contains one or more
       Documents.  If the Document is simply a reference to some print data
       stream, the reference may be used in multiple Documents in the same Job
       or even in different Jobs.  If the Document is not just a reference, but
       an actual stream of print data, the stream SHALL contain only one
       document, although there can be copies of the same document data in
       other Documents in the same or different Jobs.
       
       ISSUE: Does "An output device can be represented by at most one Printer
       object" kill "fan-in" too much?
       
       
       4.5 Object Attributes
       
       Each object type is defined by a set of possible attributes which
       describe the realization of each instance of an object.  That is, a
       Printer object is defined as set of attributes which each instance of a
       Printer object might potentially support.  In the same manner, a Job
       object is defined as a set of attributes that are associated with each
       instance of a Job object.  Some attributes are OPTIONAL, some are
       MANDATORY, and some are CONDITIONALLY MANDATORY (see section 2).  Object
       attributes are defined in section 6 of this document.
       
       4.5.1 Job Template Attribute Overview
       
       Attributes that a client may optionally include in a create request are
       called Job Template attributes.  These are described in detail in
       section 6.2.  The Printer object has associated attributes which define
       supported and default values for the Printer.
       
         - When a Job Template attribute is supplied by a client in a create
            request, the attribute and its value describe the desired job
            processing behavior.
       
         - The Printer object's supported attribute describes what behaviors
            are possible.
       
         - The Printer object's default value attribute describes what will be
            done when no other job processing information is supplied by the
            client.
       
       
       
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       4.5.2 The "best-effort" Job Attribute Overview
       
       Client supplied Job Template attributes affect the rendering,
       production, and finishing of the documents in a job.  Similar types of
       instructions may also be contained within the Page Description Language
       (PDL) of the document to be printed.  The "best-effort" attribute,
       described in detail in section 6.2.8 is provided to help manage the
       conflicts between values supplied in IPP Job Template attributes and
       corresponding instructions contained within the body of the document
       itself.  The "best-effort" attribute SHALL take one of the following
       values:
       
         - 'shall-honor-ipp-attributes': If a Printer supports this value and
            a client requests this value, the Printer guarantees that all IPP
            attribute values take precedence over embedded instructions in the
            job data (the PDL of the job's documents).
         - 'should-honor-ipp-attributes': If a Printer supports this value,
            and a client requests this value, the Printer SHOULD try to make
            sure that IPP attribute values take precedence over embedded PDL
            instructions, however there is no guarantee
       
       This "best-effort" attribute has nothing to do with conflict between
       what a Printer supports and what an IPP client requests.  If there is
       such a conflict, the Printer SHALL reject the create request.  A client
       SHOULD query the printer to find out what is supported before supplying
       specific values in a create request.
       
       
       
       
       4.6 Object Identity
       
       All instances of Printer and Job objects have an identifier attribute
       whose value is globally unique so that they can persistently and
       unambiguously referenced.  The IPP model requires that these values be
       URIs as defined by RFC 1738 and RFC 1808.  In addition to an identifier
       attribute, instances of Printer and Job objects may have a name.  An
       object name need not be unique across all instances of  all objects. The
       Printer name is chosen and set by an administrator. If not supplied by
       the client, tthe Job name is created by the Printer.  In all cases, the
       name only has local meaning, and is not constrained to be unique.
       
       To summarize, each instance of Printer and Job objects will have two
       identifying attributes:
       
         - "xxx-uri": The globally unique identifier for this object instance
         - "xxx-name": The non unique name for this object instance
       
       
       
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       Document objects sent to an IPP Printer only have names, no identifiers.
       The "document-name" attribute is used to store the name of the Document.
       This name is just of interest within the context of a Job; it need not
       be unique.
       
       If Documents are printed by reference, they are identified by URIs.
       
       
       5. IPP Operations
       
       Jobs and Printers each have a set of associated operations. End users or
       programs invoke these operations using an IPP client. The operations
       are:
       
         For a Printer object:
            Get-Operations (section 5.1.1)               MANDATORY
            Print-Job (section 5.1.2)                    MANDATORY
            Print-URI (section 5.1.3)                    OPTIONAL
            Validate-Job (section 5.1.4)                 OPTIONAL
            Create-Job (section 5.1.5)                   OPTIONAL
            Get-Jobs (section 5.1.8)                     OPTIONAL
            Get-Attributes (section 5.1.9)               OPTIONAL
       
         For a Job object:
            Send-Document (section 5.1.6)                OPTIONAL
            Send-URI (section 5.1.7)                     OPTIONAL
            Cancel-Job (section 5.1.8)                   MANDATORY
            Get-Attributes (section 5.1.9)               OPTIONAL
       
       When a client communicates with a remote IPP object, it sends an
       operation request to the URI for that object.  Each request carries
       along with it the input parameters and data required to perform the
       specified operation.  Each request requires a response from the object
       indicating success or failure of the operation including response data
       and/or error messages. The representation and encoding of the IPP
       protocol are contained in "Internet Printing Protocol: Protocol
       Specification."[23]
       
       It is assumed that URIs for IPP Printers are available to end users or
       programs that wish to invoke Printer operations.  Although NOT
       MANDATORY, it is RECOMMENDED that Printers be registered in a directory
       service which end users and programs can interrogate. "Internet Printing
       Protocol: Directory Schema"[24] defines the attributes to be associated
       with a Printer entry in a directory service.
       
       
       
       
       
       
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       5.1 Operation Semantics
       
       In this section, the IPP operations are described in terms of their
       contents and semantics including both the request and the response.
       
       In order to create a new Job object, a client MAY use one of three
       operations:
       
         - The Print-Job operation:  This operation is used if the client
            wants to create a Job with only a single Document and the document
            data is included in the request.  In this case, the client "pushes"
            the document data to the Printer.
       
         - The Print-URI operation: This operation is used if the client wants
            to create a Job with only a single Document and only a URI
            reference to the document data (not the document data itself) is
            included in the request.  In this case, the Printer "pulls" the
            document data from the location identified by the URI.
       
         - The Create-Job operation:  This operation is used if the client
            wants to create a Job with one or more Documents.  This operation
            is followed by an arbitrary number of Send-Document or Send-URI
            operations (each creating another Document for this Job).  The
            Send-Document operation includes the document data with the
            operation request (client "pushes" the document data to the
            printer), and the Send-URI operation includes only a reference (a
            URI) to the document data (the Printer "pulls" the document data
            from the referenced location).
       
       A Create-Job operation followed by a only one Send-Document operation is
       semantically equivalent to a Print-Job operation, however, for
       performance reasons, the client SHOULD use the Print-Job operation for
       all single Document Jobs. Throughout this model specification, the term
       "create request" is used to refer to any of the three operation requests
       that creates a new job object (a Print-Job request, a Print-URI request,
       or a Create-Job request).
       
       5.1.1 Get-Operations Operation
       
       Since some of the IPP operations defined in this specification are
       OPTIONAL and therefore some implementations MAY choose to not implement
       support them, this operation, Get-Operations, is a simple, MANDATORY
       operation that all implementations MUST support.  The client uses this
       operation to query a specific implementation for a list of supported
       OPTIONAL operations.
       
       
       
       
       
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       5.1.1.1 Get-Operations Request
       
       The Get-Operations Request has no parameters.
       
       5.1.1.2 Get-Operations Response
       
       The Printer SHALL return to the client the following output parameters
       as part of the Get-Operations Response:
       
         Supported Operations:
            A list of the OPTIONAL operations that this implementation
            supports.  This set of OPTIONAL operations are 'Create-Job',
            'Print-URI', 'Submit-Document', 'Submit-URI', 'Get-Jobs', and 'Get-
            Attributes'.
       
         Status
            Status information including error status
       
       
       
       5.1.2 Print-Job Operation
       
       When an end user desires to submit a print job with only one Document,
       the client sends a Print-Job Request to a Printer and receives a Print-
       Job Response from that Printer. The information in a Print-Job Request
       (along with any default information associated with the Printer) is
       sufficient for the Printer to create a Job object and then process that
       Job.  A Print-Job operation differs from a Print-URI operation in that a
       Print-Job operation contains the document data to be printed and a
       Print-URI operation only contains a reference to the document data.
       
       5.1.2.1 Print-Job Request
       
       The following elements are part of the Print-Job Request:
       
         Job Template Attributes:
            An optional set of Job Template attributes as defined in section
            6.2.  If the client supplies no Job Template attributes in the
            Create-Job Request, the Printer uses its default value attributes
            when processing the job.  Since a Print-Job operation is used for a
            Job with only one Document, the Document attributes "document-name"
            and "document-format" are also supplied by the client.  "document-
            name" is MANDATORY; "document-format" is OPTIONAL.
       
         Document Content
            The client supplies the document data.
       
       
       
       
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       The simplest Print-Job Request consists of just the Document Content and
       nothing else.  This means that the Printer SHALL create a new Job object
       with no Job Template attributes and a single contained Document.
       
       When a Printer receives a Print-Job Request, the Printer SHALL either
       accept or reject the request. The Printer SHALL accept the Print-Job
       Request and SHALL create a Job object if it is able to accept all
       attributes in the request.  The Printer SHALL reject the request and
       SHALL NOT create a Job object if the Printer rejects any attribute in
       the request. There are six cases to consider when accepting or
       rejectingJob and Document attributes:
       
         1. The client supplies a Job Template attribute named "xxx" and the
            value supplied by the client is among the values supported by the
            Printer (i.e., is among the values of the Printer's "xxx-supported"
            attribute): The "xxx" Job Template attribute is accepted.  If the
            "best-effort-supported" attribute contains the value 'shall-honor-
            ipp-attributes' the Printer SHALL guarantee the behavior
            represented by the value in the "xxx" attribute (i.e., the IPP
            attribute has precedence over any other embedded job instruction).
            If the value of the "best-effort-supported" is 'should-honor-ipp-
            attributes' then the Printer SHOULD try to realize the behavior
            requested by the client, but NEED NOT guarantee the behavior.  The
            Printer creates the Job object and associates the "xxx" attribute
            with the new Job object using  the value supplied by the client.
       
         2. The client supplies a Job Template  attribute but the attribute is
            syntactically bad: The Printer SHALL reject the job and return the
            'attribute-unsupported' error code and the name of the badly formed
            attribute (if known) in the "unsupported-attributes" response
            parameter.
       
         3. The client supplies a Job Template attribute and the attribute
            value is not among the values supported by the Printer:  The
            Printer SHALL reject the Job and return the 'attribute--value-
            unsupported' error code and the name of the unsupported attribute
            in the "unsupported-attribute-values" response parameter.
       
         4. The client supplies a Job Template attribute and the Printer does
            not support the attribute: The Printer rejects the attribute.  The
            Printer returns the 'attribute-unsupported' error code and the name
            of the rejected attribute in the "unsupported-attributes" response
            parameter.
       
       
         5. The client does not supply a Job Template  attribute, but the
            Printer supports the attribute:  The attribute is accepted and when
            the Printer creates the Job object, the Printer SHALL NOT associate
       
       
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            the attribute with the new  Job object.  When the Printer processes
            that Job, the Printer SHOULD attempt to use the behavior implied by
            the default value Printer attribute as set at the time of Job
            processing (not Job creation).  In other words, these rules allow
            for a Job object to be created without implementing some of the Job
            Template attributes.  As the Printer processes the Job, if the
            Printer supports  a corresponding default value attribute for the
            missing Job Template attribute, the Printer uses the default value.
            Depending on the value of the Printer's "best-effort" attribute,
            the Printer either guarantees the behavior corresponding to the
            default value or it does its best to realize the behavior of the
            default value.  The results of processing a Job are undefined if
            the Printer does not support the default value attribute and the
            client does not supply a value in the create request.
       
         6. The client does not supply an attribute, and the Printer does not
            support the attribute:  The Printer accepts the Job but how the Job
            is finally processed (with respect to the missing Job Template
            attributes) is undefined.
       
       
       5.1.2.2 Print-Job Response
       
       The Printer SHALL return to the client the following output parameters
       as part of the Print-Job Response:
       
         Job Identifier:
            A URI which the client SHALL use for all other operations on this
            Job
       
         Job Status:
            The following Job attributes:  job-name, job-state, and job-state-
            reasons.  The value of each attribute SHALL be from a snapshot
            taken sometime after the time the Printer receives the print
            request.  The "job-state-message" attribute is OPTIONAL.
       
            Note: Since any printer state information which affects a job's
            state is reflected in the "job-state" and "job-state-reasons"
            attributes, it is sufficient to return only these attributes and no
            specific printer status attributes.
       
       ISSUE:  Randy suggest that the following are optional returns in a
       response: job-originating-user  job-originating-host  user-locale  job-
       state  job-state-reasons  job-state-message  output-device-assigned
       time-since-submission  time-since-processing  number-of-intervening-jobs
       job-message-from-operator  time-since-completion  job-k-octets-completed
       job-impressions-completed  job-media-sheets-completed
       
       
       
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         Unsupported Attributes:
            A list of attribute names which are unsupported.  The existence of
            any attribute name in this list implies that the Job was rejected.
       
         Unsupported Attribute Values:
            A list of attribute names whose client supplied values are
            unsupported.  The existence of any attribute name in this list
            implies that the Job was rejected.
       
       ISSUE: Should we call both of these "attribute-syntax-invalid'?
       
       
         Status
            Status information including error status
       
       The simplest response SHALL consist of the job identifier, the Job
       Status attributes, and an operation status that is either an "ok" status
       or an "error" status.
       
       5.1.3 Print-URI Operation
       
       This operation is identical to the Print-Job operation (section 5.1.2)
       except that a client supplies a reference (a URI) to the document data
       to be printed rather than the document data itself.  It is up to the IPP
       server to interpret the URI and subsequently "pull" the document from
       the source referenced by the URI string.
       
       5.1.3.1 Print-URI Request
       
       The following elements are part of the Print-URI Request:
       
         Job Template Attributes:
            (see section 5.1.2.1)
       
         Document Reference:
            The client supplies the a URI reference to the document data.
       
       
       
       5.1.3.2 Print-URI Response
       
       The Printer SHALL return to the client the following output parameters
       as part of the Print-URI Response:
       
         Job Identifier:
       
       
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            (see section 5.1.2.2)
       
         Job Status:
            (see section 5.1.2.2)
       
         Unsupported Attributes:
            (see section 5.1.2.2)
       
         Unsupported Attribute Values:
            (see section 5.1.2.2)
       
         Status
            (see section 5.1.2.2)
       
       
       
       5.1.4 Validate-Job Operation
       
       This operation is identical to the Print-Job operation (section 5.1.2)
       except that a client supplies no document data or any reference to
       document data and the Printer allocates no resources (i.e., a new Job
       object) to process the job. The VALIDATE request is only used to verify
       capabilities of a printer object against whatever input parameters are
       supplied in the Validate-Job request.
       
       5.1.4.1 Validate-Job Request
       
       The following elements are part of the Validate-Job Request:
       
         Job Template Attributes:
            (see section 5.1.2.1)
       
       
       
       5.1.4.2 Validate-Job Response
       
       The Printer SHALL return to the client the following output parameters
       as part of the Validate-Job Response:
       
         Job Identifier:
            (see section 5.1.2.2)
       
         Job Status:
            (see section 5.1.2.2)
       
         Unsupported Attributes:
            (see section 5.1.2.2)
       
       
       
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         Unsupported Attribute Values:
            (see section 5.1.2.2)
       
         Status
            (see section 5.1.2.2)
       
       
       
       
       
       5.1.5 Create-Job Operation
       
       This operation is similar to the Print-Job operation (section 5.1.2)
       except that a client supplies no document data or any reference to
       document data in the Create-Job request.  This operation is followed by
       one or more Send-Document or Send-URI operations.  It is possible for a
       given implementation to only support either Send-Document or Send-URI
       but not both.  In that case, a client SHOULD NOT use an unsupported
       operation.  If a Printer supports the Create-Job operation, it MUST also
       support one of the Send-Document or Send-URI operations or both.
       
       5.1.5.1 Create-Job Request
       
       The following elements are part of the Create-Job Request:
       
         Job Template Attributes:
             (see section 5.1.2.1)
       
       
       
       5.1.5.2 Create Job Response
       
       The Printer SHALL return to the client the following output parameters
       as part of the Create-Job Response:
       
         Job Identifier:
            (see section 5.1.2.2)
       
         Job Status:
            (see section 5.1.2.2)
       
       
         Unsupported Attributes:
            (see section 5.1.2.2)
       
         Unsupported Attribute Values:
            (see section 5.1.2.2)
       
       
       
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         Status
            (see section 5.1.2.2)
       
       (see section 5.1.2.2)
       
       5.1.6 Send-Document Operation
       
       Once a Job object has been created using a Create-Job operation
       (returning a "job-uri"), a client directs a Send-Document operation to
       the newly create Job object (identified by the returned "job-uri").  The
       operation adds a new Document to the Job object. An entire document MUST
       be sent in a single Send-Document operation.SEND-DOCUMENT requests are
       directed towards the job object referenced by the "job_URI" string
       returned in a successful CREATE-JOB-RESP message.
       
       5.1.6.1 Send-Document Request
       
       The client submits the request to a Job URI.
       
       The following abstract data types are part of the Send-Document Request:
       
         Document Attributes:
            A set of Document Description attributes (section 6.4).
         Last Document Flag
            This is a boolean flag that is set if this is the last Document for
            the Job.
       
         Document Content:
            The client supplies the document data.
       
       
       5.1.6.2 Send-Document Response
       
       The following output parameters are part of the Send-Document Response:
       
         Job Status:
            (see section 5.1.2.2)
       
         Unsupported Attributes:
            (see section 5.1.2.2)
       
         Unsupported Attribute Values:
            (see section 5.1.2.2)
       
         Status:
            (see section 5.1.2.2)
       
       
       
       
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       5.1.7 Send-URI Operation
       
       This operation is identical to the Send-Document operation (see section
       5.1.6) except that a client supplies a reference (a URI) to the document
       data to be printed rather than the document data itself.  It is up to
       the IPP server to interpret the URI and subsequently "pull" the document
       from the source referenced by the URI string.
       
       5.1.7.1 Send-URI Request
       
       The client submits the request to a Job URI.
       
       The following abstract data types are part of the Send-URI Request:
       
         Document Attributes:
            (see section 5.1.6.1)
       
         Last Document Flag
            (see section 5.1.6.1)
       
         Document Reference:
            The client supplies a URI reference to the document data.
       
       
       5.1.7.2 Send-URI Response
       
       The following output parameters are part of the Send-URI Response:
       
         Job Status:
            (see section 5.1.6.2)
       
         Unsupported Attributes:
            (see section 5.1.6.2)
       
         Unsupported Attribute Values:
            (see section 5.1.6.2)
       
         Status:
            (see section 5.1.6.2)
       
       5.1.8 Cancel Job Operation
       
       This operation allows a user to cancel one specific Print Job any time
       after the print job has been established on the Printer.  Some pages may
       be printed before a job is terminated if printing has already started
       when the Cancel Job operation is received.  Only the end user who is
       also the job originator ("job-originating-user" Job attribute) can
       cancel the job using IPP 1.0.
       
       
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       5.1.8.1 Cancel-Job Request
       
       The client submits the request to a Job URI.
       
       The following abstract data types are part of the Cancel Job Request:
       
         Message:
            Optional message to the operator
       
       5.1.8.2 Cancel-Job Response
       
       The following information is part of the Cancel Job Response:
       
         Status:
            Status information including error status
       
       ISSUE:  Randy suggests that the following might be optionally returned
       in a response:  job-state  job-state-reasons  job-state-message  job-k-
       octets-completed  job-impressions-completed  job-media-sheets-completed
       time-since-submission  time-since-processing  job-originating-user  job-
       originating-host
       
       
       
       5.1.9 Get-Attributes Operation
       
       The Get-Attributes operation allows a client to obtain information from
       a Printer or Job object. The client supplies as an operation parameter
       the set of attribute names and/or attribute group names that the
       requester is interested in.  The Printer SHALL return a corresponding
       attribute list in the response with the appropriate attribute values
       filled in for each attribute (explicitly named or implicitly included in
       an attribute group) that the client supplied in the request.
       
       ISSUE: Should this be broken up into two sections - one for Printer one
       for Job?
       
       5.1.9.1 Get-Attributes Request
       
       The client SHALL submit the Get-Attributes request to a Job URI or
       Printer URI.
       
       The following input parameters SHALL be part of the Get-Attributes
       Request:
       
         Document Format:
       
       
       
       
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            The client SHALL supply this input parameter only when requesting
            attributes of the Printer object.  The Printer SHALL reject this
            request, if this input parameter is supplied for a Job object.
       
            This input parameter conditions the Printer attributes and values
            that might depend on the document format.  The Printer SHALL return
            only (1) those attributes that are supported and (2) the attribute
            values that are supported for the specified document format.  By
            specifying the document format, the client can eliminate the
            attributes and values that are not supported.
       
            If the client omits this input parameter, the effect SHALL be the
            same as if the value of the Printer's default value document format
            attribute were supplied.  It is recommended that the client always
            supply a value for document-format, since the Printer's default
            value for document-format may be 'auto-sense', in which case the
            returned attributes and values are for the union of the document
            formats that the Printer supports in its 'auto-sense' support."
       
         Requested Attributes:
            An optional set of attribute names (without values) or attribute
            group names in whose values the requester is interested.  If the
            client omits this input parameter, the effect SHALL be the same as
            if the "all" attribute group were supplied.
       
       Attributes may be requested by name or by group name.  For Jobs, the
       attribute groups include:
       
         - 'job-template': all of the Job Template attributes that apply to a
            Job object (the first column of the table in Section 6.2).
         - 'job-description': the Job Description attributes in Section 6.3.
       
       For Printers, the attribute groups include:
       
         - 'job-template': all of the Job Template attributes that apply to a
            Printer object (the last two columns of the table in Section 6.2).
         - 'printer-description': the attributes specified in Section 6.5.
       
       There are also special groups:
       
         - 'none': no attributes of the specified object.  Note: none is
            primarily useful in Get-Jobs, but can be used as a "ping" with the
            Get-Attributes operation.
         - 'all': all attributes of the specified object
       
       
       
       
       
       
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       5.1.9.2 Get-Attributes Response
       
       The Printer SHALL return the following response parameters as part of
       the Get-Attributes Response:
       
         Result Attributes:
            The requested attributes of the object with their current
            valuesSHALL
       
         Unknown Attributes:
            A list of attribute names included in the Get-Attributes request
            which are unknown by the Printer.
       
         Status:
            Status information including error status
       
       A Printer MAY be configured, for security reasons, not to return all
       attributes that a client requests. It may even return none of the
       requested attributes. In such cases, the status returned is the same as
       if the Printer had returned all requested attributes. The client cannot
       tell by such a response whether the requested attribute was present or
       absent on the Printer.
       
       In response to a "Get-Attributes" (or a "Get-Jobs") operation the
       following requirements apply to the Printer:
       
         1. If the client supplies an attribute name in the Requested
            Attribute input parameter and that attribute is supported by the
            Printer, the printer SHALL respond with all current values for that
            attribute.
       
         2. If the client supplies an attribute name in the Requested
            Attributes input parameter and that attribute is not supported by
            the Printer, the Printer SHALL respond with the attribute name in
            the "unsupported attributes" response parameter.
       
         3. If the client supplies an attribute group that is supported by the
            Printer, the Printer SHALL respond with all current values for each
            supported attribute in the group. It SHALL not respond for
            unsupported attributes in the group.
       
         4. If the client supplies an attribute group keyword that is not
            unsupported, the Printer assumes that it is an unknown attribute
            and responds  group name in the "unknown attribute list" response
            parameter.
       
       
       
       
       
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       5.1.10 Get-Jobs Operation
       
       The Get-Jobs operation allows a client to retrieve Printer attributes
       and a list of print jobs belonging to the target Printer object. A list
       of Job attribute names or attribute group names that the client is
       interested in seeing may be included in the request.
       
       This operation is like Get-Attributes, except that Get-Jobs operation
       returns attributes from more than one object.
       
       5.1.10.1 Get-Jobs Request
       
       The client SHALL submit the Get-Jobs request to a Printer URI.
       
       The following input parameters are part of the Get-Jobs Request:
       
         Limit
            This is an integer value which indicates a limit to the number of
            Jobs returned.  The limit is a "stateless limit" in that if the
            limit is n then only the first n jobs are returned in the Get-Jobs
            Response; there is no mechanism to allow for the "next" n jobs.
            The limit applies across all Job States requested.  For example, if
            the limit if 50, and there are 75 jobs in the 'completed' state and
            25 in the 'pending state' and the client requests first 'completed
            jobs' and then 'pending' jobs, only the oldest 50 'completed' jobs
            are returned.  The other 25 'completed' jobs are not returned and
            neither are any of the 'pending' jobs returned.
       
         Requested Job Attributes:
            A optional set of attribute names (without values) or attribute
            groups names in whose values the requester is interested from each
            of the jobs on the specified Printer.  The attribute group names
            are the same as for the Get-Attributes operation for the Job
            object.  If the client omits this input parameter, the effect SHALL
            be the same as if the "job-uri" attribute were supplied.
       
       5.1.10.2 Get-Jobs Response
       
       The Printer SHALL return the following output parameters as part of the
       Get-Jobs Response:
       
         Result Attributes:
            The result includes zero or more objects each with zero or more
            attributes.  Each Job is returned in chronological order.  This
            order is explicitly defined to be: oldest to newest with respect to
            completion time, either actual or expected. Jobs that are in the
            'pending-held' state SHALL appear in their position as if they were
            'pending'  (otherwise, a user might be deceived by jobs that move
       
       
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            from 'pending-held' to 'pending' as seeming to jump ahead in the
            queue).
       
            If the client did not supply any Job attributes, the Printer SHALL
            assume that the client is implicitly requesting  the "job-uri"
            attribute (that is no other Job attributes are returned, but the
            Job URI for each Job).
       
         Status
            Status information including error status
       
       A Printer MAY be configured, for security reasons, not to return all
       attributes that a client requests. It may even return none of the
       requested attributes. In such cases, the status returned is the same as
       if the Printer had returned all requested attributes. The client cannot
       tell by such a response whether the requested attribute was present or
       absent on the Printer.
       
       ISSUE: Some people still have complaints about this security statement.
       
       
       5.2 Operation Status Codes and Messages
       
       An operation status code provides information on the processing of a
       request.  A message provides a short textual description of the Status.
       The status code is intended for use by automata and a message is
       intended for the human user.  An IPP application (i.e. a browser, GUI,
       print driver or gateway) is not required to examine or display the
       message.  Status codes and suggested corresponding messages are included
       in section 12 "APPENDIX A - Status Codes".
       
       
       6. Object Attributes
       
       This section describes the attributes with their corresponding syntaxes
       and values that are part of the IPP model. The sections below show the
       objects and their associated attributes which are included within the
       scope of this protocol.  Many of these attributes are derived from other
       relevant specifications:
       
         - ISO/IEC 10175 DPA (Final, June 1996)
         - RFC 1759 Printer MIB (Proposed Standard, May 1995)
         - Internet-Draft: Printer MIB (Draft Standard in progress, December
            1996)
         - Internet-Draft: Job Monitoring MIB (I-D in progress, March 1997)
       
       Each attribute is uniquely identified in this document using a "keyword"
       (see section 2.2.1).  The keyword in included in the section header
       
       
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       describing that attribute. Not only are attributes uniquely identified
       with keywords, some attributes take on a syntax which is a set of
       keywords.
       
       
       6.1 Attribute Syntaxes
       
       The following table shows the basic syntax types that a client and
       server SHALL be able to handle.
       
         text:  a sequence of characters, length: 0 to 4095, any characters.
            This syntax type is used for free form human readable text intended
            for human consumption.
       
         name:  a sequence of characters, length: 1 to 255, any characters.
            This syntax type is used for referencing some object or entity via
            a user-friendly string, such as a Printer name, a document name, a
            user name, or a host name.
       
         fileName:  a sequence of characters, length: 1 to 1024, any
            characters.  This syntax type is used for referencing some file.
            The limit is the same as in POSIX and Microsoft NT.
       
         keyword:  a sequence of characters, length: 1 to 255, containing only
            the characters ASCII letters, ASCII digits, hyphen ("-"),
            underscore ("_").  The first character MUST be an ASCII letter.
            This syntax type is used for enumerating semantic identifiers of
            entities in the abstract protocol (specified in this document).
            These entities can be attribute names or values of attributes.
            When a keyword is used to represent an attribute (its name), it
            MUST be unique within the full scope of IPP objects and attributes.
            When a keyword is used to represent a value of an attribute, it
            MUST be unique just within the scope of that attribute.  That is,
            the same keyword can not be used for two different values within
            the same attribute to mean two different semantic ideas.  However,
            the same keyword can be used across two or more attributes,
            representing different semantic ideas for each attribute.
       
         uri:  a sequence of characters as defined in rfc1738 and rfc1808.
            This syntax type is used for carrying Universal Resource
            Identifiers.
       
         uriScheme:  a sequence of characters representing the URI Scheme.
            These include 'http' for HTTP schemed URIs (e.g., http://...), and
            'ftp' for FTP schemed URIs (e.g., ftp://...).
       
         locale:  a standard identifier for country and language.  The values
            for this syntax type are taken from RFC 1766 [26].
       
       
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         octetString:  a sequence of octets.  This syntax type is used for
            opaque data, such as the document-content.
       
         boolean:  two values of 'true' and 'false'.  This syntax type is like
            a keywordSet, but there are only two values. Note: An application
            might use a checkbox for an attribute with this syntax type.
       
         integer:  an integer value that is in the range from -2**31 to 2**31
            - 1.  Each attribute specifies the range constraint explicitly if
            the range is different from the full range of possible integer
            values (e.g., 0 - 100 for the "job-priority" attribute).
       
         dateTime:  a standard, fixed length representation of date and time
            (to the nearest second) as defined in RFC 1123 [27].  For example,
            Sun, 06 Nov 1994 08:49:37 GMT.  This is a fixed-length subset of
            that defined by RFC 1123  (an update to RFC 822).  All values MUST
            be represented in Greenwich Mean Time (GMT). This is indicated by
            the inclusion of "GMT" as the three-letter abbreviation for time.
       
         seconds:  a non-negative integer with implicit units of seconds.
            This is used for relative time.
       
         milliseconds:  a non-negative integer with implicit units of
            milliseconds.  This is used for relative time.
       
         1setOf  X:  1 or more values of type X.  This syntax type is used for
            multi-valued attributes, whose value is a set of values.  Note:
            The syntax type is called "1setOf" to indicate that set of values
            SHALL NOT be empty (a set of size 0).
       
         rangeOf  X:  a range of value of type X.  This syntax type is used
            for ordered values (numeric, lexical, etc.) such as integers.
       
       
       6.1.1 Attribute Extensibility
       
         This document uses prefixes to the "keyword" basic syntax type in
         order to communicate extra information to the reader through its
         name. This extra information need not be represented in an
         implementation because it is unimportant to a client or Printer.  The
         table below describes the prefixes and their meaning.
       
         "type1":  The editor MUST revise the IPP standard to add a new name.
            No private names are allowed.
       
         "type2":  Implementers can, at any time, add new values by proposing
            them to the PWG for registration (or an IANA-appointed registry
       
       
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            advisor after the PWG is no longer certified) where they are
            reviewed for approval.  IANA keeps the registry.  Implementers can
            support private (unregistered) with a suitable distinguishing
            prefix, such as "-xxx-" where xxx is the company name registered
            with IANA for use in domain names.
       
         "type3":  Implementers can, at any time, add new values by submitting
            a registration request directly to IANA, no PWG or IANA-appointed
            registry advisor review is required.  Implementers can support
            private (unregistered) names with a suitable distinguishing prefix,
            such as "-xxx-" where xxx is the company name registered with IANA
            for use in domain names.
       
         "type4":  Anyone (system administrators, system integrators, site
            managers, etc.) can, at any time, add new installation-defined
            names to a local system. Care SHOULD be taken by the implementers
            to see that keywords do not conflict with other keywords defined by
            the standard or as defined by the implementing product. There is no
            registration or approval procedure for type 4 keywords.
       
       Each of the four types above assert some sort of registry or review
       process in order to be valid.  "type1" values are only valid if the
       specification is updated, "type2" values are only valid if the PWG or an
       IANA approved review process approves them, "type3" values are only
       valid if IANA registers the value with no review process required, and
       "type4" values are always valid (there is no review or registration
       process required).  Any typeN value MAY be registered using a process
       for some typeM where M is less than N, however such registration is NOT
       REQUIRED.  For example, a type4 value MAY be registered in a type 1
       manner (by being included in a future version of an IPP specification)
       however it is NOT REQUIRED.
       
       Note: This specification defines keyword values for all of the above
       types, including type4 keywords.
       
       
       6.2 Job Template Attributes
       
       Job Template attributes describe job processing behavior.  Take for
       example, a generic Job Template attribute called "xxx":
       
         1. "xxx" is optionally supplied by the client in a create request.
            If "xxx" is supplied, the client is specifying that the Printer
            will apply a specific job processing behavior to this job while
            processing the Job.  When "xxx" is not supplied, the client expects
            the Printer will apply the default job processing behavior.
       
       
       
       
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         2. "xxx-supported" is a Printer attribute that describes which
            behaviors are supported by a Printer.  "xxx-supported" is a
            CONDITIONALLY MANDATORY  attribute which means that the Printer
            only supports the attribute if it is capable of realizing one or
            more of the behaviors associated with the attribute and its values.
            A client can query the Printer and find out what behaviors are
            supported by inspecting at the values in the "xxx-supported"
            attribute.
       
         3. The Printer also supports a default value attribute named "xxx".
            This default value attribute describes what will be done when no
            other job processing information is supplied by the client (either
            explicitly as an IPP attribute in the create request or implicitly
            as an embedded instruction within the job data).  Along with the
            supported attribute, the default value attribute is also
            CONDITIONALLY MANDATORY.  However, if the Printer supports the
            "xxx-supported" attribute, the Printer MUST support the
            corresponding default value attribute and vice versa.
       
         4. If a client application wishes to present an end user with a list
            of supported and default values from which to choose, the client
            program SHOULD query the supported and default value attributes.
            The values that the client then supplies in the create request will
            all fall within the supported values at the Printer.  When querying
            the Printer, the client MAY enumerate each attribute by name in the
            Get-Attributes Request, or the client MAY just name the "printer-
            job-template" group in order to get the complete set of supported
            and default value attributes which are supported.
       
       The "job-priority" attribute is an example of a Job Template attribute.
       It is an integer in the range from 1 to 100.  A client can query the
       Printer for the "job-priority-supported" attribute and the "job-
       priority" default value attribute.  The supported attribute contains a
       set of supported priority values (a range).  The default value attribute
       contains the job priority value that will be used for a new job if the
       client does not supply one in the create request.  If the client does
       supply the "job-priority" attribute, the Printer validates the value to
       make sure that it falls within the range of supported values.  If the
       client-supplied value is supported, the Job object is created and the
       "job-priority" attribute is populated with that value.  The Job object,
       when queried, returns the value supplied by the client.  If the client
       does not supply a "job-priority" value in the create request, the Job
       object is created, but no "job-priority" attribute is associated with
       the Job.  The client queries the Printer's default value "job-priority"
       value to find out at what priority the job will be processed.
       
       
       
       
       
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       The following table summarize the names, relationships, and conformance
       requirements for all Job Template attributes.  The following general
       rules apply to implementation requirements:
       
         1. In a create request, all Job Template attributes are OPTIONAL.
       
         2. In a Printer Object, all supported attributes are CONDITIONALLY
            MANDATORY.
       
         3. All Printer default value attributes are CONDITIONALLY MANDATORY.
            However, if the Printer implements that "supported" attribute then
            the Printer MUST also implement the default value attribute as
            well. and vice versa.
       
       The table only shows exceptions to the above rules.   The first column
       of the table (Job) shows the name and syntax for each Job Template
       attribute in the Job object (in the create request, the same name and
       syntax is used).  Section All of the attributes in the first column make
       up the groupThe last two columns show the name and syntax for each Job
       Template attribute in the Printer object (the default value attribute
       and the supported attribute).  A "No" in the table means the Printer
       SHALL NOT support the attribute.  A "MAN" indicates that the attribute
       is MANDATORY.
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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       +----------------------+----------------------+----------------------+
       |    Job               |Printer: Default Value|  Printer: Supported  |
       +----------------------+----------------------+----------------------+
       | job-name             | No                   | No                   |
       | (name, MAN)          |                      |                      |
       +----------------------+----------------------+----------------------+
       | job-sheets           | job-sheets           |job-sheets-supported  |
       | (type4 keyword)      | (type4 keyword)      |(1setOf type4 keyword)|
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | notify-events        | notify-events        | notify-events-       |
       |(1setOf type2 keyword)|(1setOf type2 keyword)| supported            |
       |                      |                      |(1setOf type2 keyword)|
       +----------------------+----------------------+----------------------+
       |notify-addresses      |No                    |notify-addresses      |
       |(1setOf uri)          |                      |-supported            |
       |                      |                      |(1setOf uri scheme)   |
       +----------------------+----------------------+----------------------+
       | job-priority         | job-priority         |job-priority-supported|
       | (integer 1-100)      | (integer 1-100)      |(rangeOf integer      |
       |                      |                      | 1-100)               |
       +----------------------+----------------------+----------------------+
       | job-hold-until       | job-hold-until       | job-hold-until-      |
       | (type4 keyword)      | (type4 keyword)      | supported            |
       |                      |                      |(1setOf type4 keyword)|
       +----------------------+----------------------+----------------------+
       |multiple-documents-are|multiple-documents-are|multiple-documents-are|
       | (type2 keyword)      | (type2 keyword)      |-supported            |
       |                      |                      |(1setOf type2 keyword)|
       +----------------------+----------------------+----------------------+
       | best-effort          | best-effort          | best-effort-supported|
       | (type2 keyword)      | (type2 keyword, MAN) |(1setOf type2 keyword,|
       |                      |                      |MAN)                  |
       +----------------------+----------------------+----------------------+
       | media                | media                | media-supported      |
       | (type4 keyword)      | (type4 keyword)      |(1setOf type4 keyword)|
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | number-up            | number-up            | number-up-supported  |
       | (type3 keyword)      | (type3 keyword)      |(1setOf type3 keyword)|
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | sides                | sides                | sides-supported      |
       | (type2 keyword)      | (type2 keyword)      |(1setOf type2 keyword)|
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | resolution           | resolution           | resolution-supported |
       
       
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       | (type2 keyword)      | (type2 keyword)      |(1setOf type2 keyword)|
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | quality              | quality              | quality-supported    |
       | (type2 keyword)      | (type2 keyword)      |(1setOf type2 keyword)|
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | finishings           | finishings           | finishings-supported |
       |(1setOf type2 keyword)|(1setOf type2 keyword)|(1setOf type2 keyword)|
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | copies               | copies               | copies-supported     |
       | (integer: 0 - MAX)   | (integer: 0 - MAX)   | (rangeOf integer     |
       |                      |                      |  0- MAX)             |
       +----------------------+----------------------+----------------------+
       | document-format      | document-format      | document-format-     |
       | (type2 keyword)      | (type2 keyword)      | supported            |
       |                      |                      |(1setOf type3 keyword)|
       +----------------------+----------------------+----------------------+
       | compression          | No                   | compression-supported|
       | (type3 keyword)      |                      |(1setOf type3 keyword)|
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | job-k-octets         | No                   |job-k-octets-supported|
       | (integer)            |                      | (rangeOf integer)    |
       |                      |                      |                      |
       +----------------------+----------------------+----------------------+
       | job-impressions      | No                   | job-impressions-     |
       | (integer)            |                      | supported            |
       |                      |                      | (rangeOf integer)    |
       +----------------------+----------------------+----------------------+
       | job-media-sheets     | No                   | job-media-sheets-    |
       | (integer)            |                      | supported            |
       |                      |                      | (rangeOf integer)    |
       +----------------------+----------------------+----------------------+
       
       6.2.1 job-name (name)
       
       This attribute is the name of the job.  It is a name that is more user
       friendly than the "job-uri" attribute value.  It does not need to be
       unique.
       
       If "job-name" is not supplied in the create request, the Printer, on
       creation of the Job, SHALL generate a name.  The name MAY be generated
       using the name of the first Document in the Job ((the "document-name"
       attribute)..  If "job-name" is supplied in the create request, the
       Printer SHALL use its value as the name of the created Job.
       
       
       
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       6.2.2 job-sheets (type4 keyword)
       
       This attribute determines which if any banner page(s) SHALL be printed
       with a job.
       
       Standard values are:
       
         'none': no job sheet is printed
         'standard': a site specific standard job sheet is printed
       
       To force no job sheets, the system administrator SHALL set the supported
       value to only 'none'.  To force the use of banner pages, the supported
       values SHALL not include 'none'.  If a client requests 'none' in the
       create request, the request is rejected.
       
       6.2.3 notify-events (1setOf type2 keyword)
       
       This attribute specifies the events for which the end user desires some
       sort of notification.  The "notify-addresses" attribute is used to
       describe the destination addresses for these events.
       
       Standard values are:
       
         'none': the Printer SHALL not notify.
         'all': the Printer SHALL notify when any of event occurs.
         'job-completion':  the Printer SHALL notify when the job containing
            this attribute completes with or without errors.
         'job-canceled':  the Printer SHALL notify when the job containing
            this attribute is canceled by the end-user or by the operator, or
            aborts before completion.
         'job-problems':  the Printer SHALL notify when this job has a problem
            while this job is printing. Problems include any of the "job-state-
            reasons" or "printer-state-reason" values.
         'printer-problems': the Printer SHALL notify when any job, including
            this job, is affected by a Printer problem (the printer has moved
            to the stopped state and there is a reason in the printer-state-
            reasons attribute) while this job is waiting to print or printing.
            Problems include any of the "job-state-reasons" or "printer-state-
            reason" values.
       
       ISSUE:  Should these correspond with Job states job-completed, job-
       completed-aborted, job-completed-canceled?
       
       
       6.2.4 notify-addresses (1setOf uri)
       
       This attribute describes both where (the address) and how (the mechanism
       for delivery ) events are to be delivered. The Printer SHALL use this
       
       
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       attribute as the set of addresses and methods for sending messages when
       an event occurs that the end user (job submitter) has registered an
       interest in.
       
       Standard uri scheme values are:
       
         'mailto': email is used
         'http': an HTTP  method is used to add HTML formatted events to the
            end of the specified HTML file.
         'ftp': FTP is used to append a record at the end of a specified text
         file.
       
       6.2.5 job-priority (integer(1:100))
       
       This attribute specifies a priority for scheduling the print-job. A
       higher value specifies a higher priority. The value 1 is defined to
       indicate the lowest possible priority. The value 100 is defined to
       indicate the highest possible priority.  Among those jobs that are ready
       to print, a Printer SHALL print all jobs with a priority value of n
       before printing those with a priority value of n-1 for all n.  The
       mapping of vendor-defined priority over this range is implementation-
       specific.
       
       6.2.6 job-hold-until (type4 keyword)
       
       This job attribute specifies the named time period during which the Job
       print job SHALL become a candidate for printing.
       
       Standard values for named time periods are:
       
         'no-hold': immediately, if there are not other reasons to hold the
            job.
         'day-time': during the day.
         'evening': evening
         'night': night
         'weekend': weekend
         'second-shift': second-shift
         'third-shift': third-shift (after midnight)
       
       
       An administrator SHALL associate allowable print times with a named time
       period (by means outside IPP 1.0).  An administrator is encouraged to
       pick names that suggest the type of time period.
       
       If the value of this attribute specifies a time period that is in the
       future, the Printer SHALL add the 'job-hold-until-specified' value to
       the job's "job-state-reasons" attribute and SHALL NOT schedule the
       print-job for printing until the specified time-period arrives.  When
       
       
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       the specified time period arrives, the Printer SHALL remove the 'job-
       hold-until-specified' value from the job's "job-state-reason attribute"
       and, if no other reasons remain, SHALL consider the job as a candidate
       for processing.
       
       If this job attribute value is the named value "'no-hold'", or the time
       period has already started , the job SHALL be a candidate for processing
       immediately.
       
       6.2.7 multiple-documents-are (type2 keyword)
       
       This job attribute is relevant only if a job consists of two or more
       documents. It controls finishing operations, job-sheet placement, and
       the order of documents when the copies attribute exceeds 1.
       
       ISSUE: Change name to "finishing-for-multiple-documents"??
       
       Standard values are:
       
         'single-document': If the files for the job are a and b, then files a
            and b SHALL be treated as a single document for finishing
            operations. Also, there SHALL be no slip sheets between files a and
            b. If more than one copy is made, the ordering SHALL be a, b, a, b,
            ....
         'separate-documents-uncollated-copies': If the files for the job are
            a and b, then each file SHALL be treated as a single document for
            finishing operations. Also, a client may specify that a slip sheet
            be placed between files a and b.  If more than one copy is made,
            the ordering SHALL be a, a, b, b, ....
         'separate-documents-collated-copies': If the files for the job are a
            and b, then each file SHALL be treated as a single document for
            finishing operations. Also, a client may specify that a slip sheet
            be placed between files a and b. If more than one copy is made, the
            ordering SHALL be a, b, a, b, ....
       
       
       Both of the 'separate-xxx' values force each new document to start on a
       new media sheet.
       
       6.2.8 best-effort (type2 keyword)
       
       A client supplies Job Template attributes to affect the rendering,
       production and finishing of the documents in the job.  Similar types of
       instructions may also be contained in the document to be printed, that
       is, within the Page Description Language (PDL) of the document data.  If
       there is a conflict between the value of one of these IPP Job Template
       attributes, and a corresponding instruction in the document (either
       implicit or explicit), it is desirable that the value of the attribute
       
       
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       SHALL take precedence over the document instruction.  Until companies
       that supply interpreters for PDLs, such as PostScript and PCL allow a
       way to external attributes (such as IPP attributes) to take precedence
       over internal job production instructions, a Printer might not be able
       to support the semantics that IPP attributes override (take on a higher
       precedence) the embedded PDL instructions.   Therefore, this attribute
       gives the end user some ability to influence, or at least understand,
       how a particular Printer implementation handles these conflicts.
       
       This attribute takes on the following values:
       
         - 'shall-honor-ipp-attributes': If a Printer supports this value and
            a client requests this value, the Printer guarantees that all IPP
            attribute values take precedence over embedded instructions in the
            job data (the PDL of the job's documents).
         - 'should-honor-ipp-attributes': If a Printer supports this value,
            and a client requests this value, the Printer SHOULD try to make
            sure that IPP attribute values take precedence over embedded PDL
            instructions, however there is no guarantee
       
       ISSUE: Should these be 'shall-honor-attribute-precedence' and 'should-
       honor-attribute-prcedence'?
       
       A Printer SHALL implement the "best-effort-supported" attribute.  Notice
       that since 'should-honor-ipp-attributes' does not offer any type of
       guarantee, a Printer may not do a very "good" job of implementing the
       semantics of "should", but it would still be a conforming
       implementation.
       
       If there is ever a conflict between what a Printer supports and what an
       IPP client requests, the Printer SHALL reject the print request.  A
       client SHOULD query the printer to find out what is supported before
       making a request.  This ensures that all requested attribute values are
       supported.
       
       ISSUE: Should this be called "effort-level" rather than "best-effort"?
       
       
       
       If the value of this attribute is 'shall-honor-ipp-attributes', the
       implementation MUST guarantee that the IPP attribute values take
       precedence over any related job processing instructions in the PDL Job's
       document data.  This can be done by modifying the interpreter within the
       output device itself to understand IPP attributes, or by merging theses
       Job Template attributes directly into the document data, or in any other
       implementation specific manner.  In any case, the semantics of 'shall-
       honor-ipp-attributes' MUST be preserved.
       
       
       
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       Note: Since 'should-honor-ipp-attributes' does not offer any type of
       guarantee, a Printer may not do a very "good" job of implementing the
       semantics of 'should', but it would still be a conforming
       implementation.
       
       
       
       6.2.9 media (type4 keyword)
       
       This job attribute identifies the medium that the Printer SHALL use for
       all pages of the document regardless of what media are specified within
       the document.
       
       The values for "media" include medium-names, medium-sizes, input-trays
       and electronic forms so that one attribute specifies the media. If a
       printer allows a client to specify a medium name as the value of this
       attribute, such a medium name implicitly selects an input-tray that
       contains the specified medium.  If a printer allows a client to specify
       a medium size as the value of this attribute, such a medium size
       implicitly selects a medium name which in turn implicitly selects an
       input-tray that contains the medium with the specified size.  If a
       printer allows a client to specify an input-tray as the value of this
       attribute, such an input-tray implicitly selects the medium that is in
       that input-tray at the time the job prints. This case includes manual-
       feed input-trays.  If a printer allows a client to specify an electronic
       form as the value of this attribute, such an electronic form implicitly
       selects a medium-name which in turn implicitly selects an input-tray
       that contains the medium specified by the electronic form. The
       electronic form also implicitly selects an image that the Printer SHALL
       merge with the data from the document as its prints each page.
       
         Standard values are (taken from ISO DPA and the Printer MIB) and are
            listed in section 14.
       
       6.2.10 number-up (type3 keyword)
       
       This job attribute specifies the number of source page-images to impose
       upon a single side of an instance of a selected medium.
       
       Standard values are:
       
         'none': The Printer SHALL not include any embellishments and SHALL
            place one logical page on a single side of an instance of the
            selected medium without any translation, scaling, or rotation.
         'one': The Printer SHALL place one logical page on a single side of
            an instance of the selected medium (MAY add some sort of
            translation, scaling, or rotation).
       
       
       
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         'two': The Printer SHALL place two logical page on a single side of
            an instance of the selected medium (MAY add some sort of
            translation, scaling, or rotation).
         'four': The Printer SHALL place four logical page on a single side of
            an instance of the selected medium (MAY add some sort of
            translation, scaling, or rotation).
       
       This attribute primarily controls the translation, scaling and rotation
       of page images, but a site may choose to add embellishments, such as
       borders to each logical page.
       
       6.2.11 sides (type2 keyword)
       
       This attribute specifies how source page-images are to be imposed upon
       the sides of an instance of a selected medium.
       
       The standard values are:
       
         'one-sided': imposes each consecutive source page-image upon the same
            side of consecutive media sheets.
         'two-sided-long-edge': imposes each consecutive pair of source page-
            image upon front and back sides of consecutive media sheets, such
            that the orientation of each pair of source-pages on the medium
            would be correct for the reader as if for binding on the long edge.
            This imposition is sometimes called 'duplex'.
         'two-sided-short-edge': imposes each consecutive pair of source page-
            image upon front and back sides of consecutive media sheets, such
            that the orientation of each pair of source-pages on the medium
            would be correct for the reader as if for binding on the short
            edge.  This imposition is sometimes called 'tumble' or 'head-to-
            toe'.
       
       'two-sided-long-edge', 'two-sided-short-edge', 'tumble'. 'duplex', and
       'head-to-toe' all work the same for portrait or landscape, that is,
       'head-to-toe' is 'tumble' in portrait but 'duplex' in landscape.  'head-
       to-head' also switches between 'duplex' and 'tumble' when using portrait
       and landscape modes.
       
       6.2.12 printer-resolution (type2 keyword)
       
       This job attribute specifies the resolution that the Printer SHOULD use.
       
       The values are type2 keywords which represent single integers or pair of
       integers. The latter are to specify the resolution when the x and y
       dimensions differ. When two integers are specified, the first is in the
       x direction, i.e., in the direction of the shortest dimension of the
       medium, so that the value is independent of whether the printer feeds
       long edge or short edge first.
       
       
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       The standard values are:
       
       ISSUE: TBD   normal: res-100:  res-300x300:  ...
       
         'normal':
         'res-100':
         'res-200':
         'res-240':
         'res-300':
         'res-600':
         'res-800':
         'res-1200':
         'res-1800':
         'res-100x200':
         'res-300x600':
         'res-600x300':
         'res-400x800':
         'res-800x400':
         'res-600x1200':
         'res-1200x600':
         'res-1800x600':
       
       6.2.13 print-quality (type2 keyword)
       
       This job attribute specifies the print quality that the Printer SHOULD
       use.
       
       The standard values are:
       
         draft: lowest quality available on the printer
         normal: normal or intermediate quality on the printer
         high: highest quality available on the printer
       
       
       6.2.14 copies (integer(1:2**31 - 1))
       
       This job attribute specifies the number of copies of the job to be
       printed.
       
       Note: The effect of this attribute on jobs and documents is controlled
       by the "multiple-documents-are" job attribute (section 6.2.7).
       
       
       
       6.2.15 finishing (1setOf type2 keyword)
       
       This job attribute identifies the finishing operations that the Printer
       SHOULD apply to each copy of each printed document in the job where the
       
       
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       definition of a copy is controlled by the "multiple-documents-are" Job
       attributes.
       
       Standard values are:
       
         none:
         staple:
         ...
       6.2.16 document-format (type2 keyword)
       
       This optional attribute defines the document format for each Document in
       a Job.  The standard values for this attribute are keywords.  Since the
       complete list is rather long, the full enumeration of standard values is
       found in section 13 APPENDIX B - "document-format" Values.
       
       6.2.17 compression (type3 keyword)
       
       This attribute identifies compression algorithms used for compressed
       document data.
       
       Standard values for this attribute are:
       
         'none': no compression is used.
         'zip':ZIP compression technology
         'tar': UNIX TAR compression technology
       
       
       6.2.18 job-k-octets (integer(0:2**31 - 1))
       
       This Job attribute specifies the total size of the job in K octets,
       i.e., in units of 1024 octets.  The value SHALL be rounded up, so that a
       job between 1 and 1024 octets SHALL be indicated as being 1K, 1025 to
       2048 SHALL be 2, etc. This attribute is not intended to be a counter as
       in the Job Monitoring MIB;  it is intended to be useful routing and
       scheduling information if known.  If the client does not supply this
       attribute in the create request, the Printer might not be able to
       compute this value at the time the Job is created.
       
       6.2.19 job-impressions (integer(0:2**31 - 1))
       
       This job attribute specifies the total size of the job in impressions.
       This attribute is not intended to be a counter as in the Job Monitoring
       MIB;  it is intended to be useful routing and scheduling information if
       known.  The Printer SHALL try to compute the value if it is not supplied
       in the create request.  The Printer might not be able to compute this
       value (if not supplied by the client in the request) at the time the Job
       is created.  If not, the Printer may support this attribute at any later
       time as it is able to compute the total size of the Job.
       
       
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       6.2.20 job- media-sheets (integer(0:2**31 - 1))
       
       This job attribute specifies the total size of the job in media-sheets.
       This attribute is not intended to be a counter as in the Job Monitoring
       MIB; it is intended to be useful routing and scheduling information if
       known. The Printer SHALL try to compute the value if it is not supplied
       in the creaet request.  The Printer might not be able to compute this
       value (if not supplied by the client in the request) at the time the Job
       is created.  If not, the Printer may support this attribute at any later
       time as it is able to compute the total size of the Job.
       
       
       6.3 Job Description Attributes
       
       The attributes in this section form the attribute group called "job-
       description".  The following table summarizes these attributes.  The
       third column indicates whether the attribute is a MANDATORY attribute.
       If it is not MANDATORY, then it is OPTIONAL.
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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       +----------------------------+----------------------+----------------+
       |      Attribute             |     Syntax           |   MANDATORY?   |
       +----------------------------+----------------------+----------------+
       | job-uri                    | uri                  |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | job-uri-user               | uri                  |                |
       +----------------------------+----------------------+----------------+
       | job-originating-user       | name                 |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | job-originating-host       | name                 |                |
       +----------------------------+----------------------+----------------+
       | user-locale                | locale               |                |
       +----------------------------+----------------------+----------------+
       | job-state                  | type1 keyword        |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | job-state-reasons          | 1setOf type2 keyword |                |
       +----------------------------+----------------------+----------------+
       | job-state-message          | text                 |                |
       +----------------------------+----------------------+----------------+
       | output-device-assigned     | name                 |                |
       +----------------------------+----------------------+----------------+
       | time-since-pending         | milliseconds         |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | time-since-processing      | milliseconds         |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | time-since-completed       | milliseconds         |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | number-of-intervening-jobs | integer              |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | job-message-from-operator  | text                 |                |
       +----------------------------+----------------------+----------------+
       | job-k-octets-completed     | integer              |                |
       +----------------------------+----------------------+----------------+
       | job-impressions-completed  | integer              |                |
       +----------------------------+----------------------+----------------+
       | job-media-sheets-completed | integer              |                |
       +----------------------------+----------------------+----------------+
       
       6.3.1 job-uri (uri)
       
       This attribute contains the URI for the job.  The Printer, on receipt of
       a new job, SHALL generate a URI which identifies the job on the Printer.
       The Printer, SHALL return the value of the "job-uri" attribute as part
       of the response to a create request.   The precise format of a job URI
       SHALL be implementation dependent.
       
       
       
       
       
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       6.3.2 job-uri-user (uri)
       
       Similar to "job-uri", this attribute contains the URI referencing an
       HTML page containing information about the Job.
       
       6.3.3 job-originating-user (name)
       
       This attribute specifies the user name of the person submitting the
       print job.  The Printer SHALL set this attribute to the most authentic
       name that it can obtain from the protocol over which the operation was
       received from the client.
       
       6.3.4 job-originating-host (name)
       
       This attribute identifies the originating host of the job. The Printer
       SHALL set this attribute to the most authentic host name it can obtain
       from the protocol over which the operation was received from  the
       client.
       
       6.3.5 user-locale (type3 keyword)
       
       This attribute identifies the locale of the job, i.e, the country,
       language, and coded character set. The Printer sets this attribute to
       the most authentic value it can obtain from the protocol over which the
       Print operation was received from the client.
       
       The Printer SHALL use this attribute to determine the locale for
       notification messages that it sends.
       
       6.3.6 job-state (type1 keyword)
       
       
       
       6.3.7 job-state-reasons (1setOf  type2 keyword)
       
       
       
       6.3.8 job-state-message (text)
       
       This attributes specifies supplemental information about the Job State
       in human readable text.  It SHALL be set by the Printer.
       
       6.3.9 output-device-assigned (name)
       
       This attribute identifies the Output Device to which the Printer has
       assigned this job.  If an output device implements an embedded IPP
       Printer, the Printer NEED NOT set this attribute.  If a Print Server
       
       
       
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       implements a Printer, the value MAY be empty until the Printer assigns
       an output device to the job.
       
       6.3.10 time-since-pending (milliseconds)
       
       This attribute indicates the amount of time that has passed since the
       Job was first put into the pending state..
       
       6.3.11 time-since-processing (milliseconds)
       
       This attribute indicates the amount of time that has passed since the
       Job first entered the processing state.
       
       6.3.12 time-since-completed (milliseconds)
       
       This attribute indicates the amount of time that has passed since the
       Job was completed.
       
       6.3.13 number-of-intervening-jobs (integer(0:2**31 - 1))
       
       This attribute indicates the number of jobs that are "ahead" of this job
       in the current scheduled order.  For efficiency, it is only necessary to
       calculate this value when an operation is performed that requests this
       attribute.
       
       Note: This attribute is necessary since an end user may request just
       their own jobs and they need some relative position indicator if there
       are other jobs interspersed in the waiting list which are not returned
       in the response or cannot be because of site security policy
       restrictions.
       
       6.3.14 job-message-from-operator (text)
       
       This attribute provides a message from an operator, system administrator
       or "intelligent" process to indicate to the end user the reasons for
       modification or other management action taken on a job.
       
       6.3.15 job-k-octets-completed (integer(0:2**31 - 1))
       
       This attribute specifies the number of octets completed in K octets,
       i.e., in units of 1024 octets.  The value SHALL be rounded up, so that a
       job between 1 and 1024 octets SHALL be indicated as being 1K, 1025 to
       2048 SHALL be 2, etc. This attribute is intended to be a counter as in
       the Job Monitoring MIB.
       
       
       
       
       
       
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       6.3.16 job-impressions-completed  (integer(0:2**31 - 1))
       
       This job attribute specifies the number of impressions completed. This
       attribute is intended to be a counter as in the Job Monitoring MIB.
       
       6.3.17 job-media-sheets-completed (integer(0:2**31 - 1))
       
       This job attribute specifies the media-sheets completed. This attribute
       is intended to be a counter as in the Job Monitoring MIB.
       
       ISSUE: Should the above three attributes be regularly named as job-size-
       in-xxx-yyy where xxx is k-octets, impressions and media sheets and where
       yyy is a job state pending, processing and completed. So job-impressions
       becomes job-size-in-impressions-pending and job-impressions-completed is
       job-size-in-impressions-processing while printing and job-size-in-
       impressions-completed  when the job completed. Thus job-impressions-
       completed doesn't serve two functions.
       
       6.4 Document Attributes
       
       This group of attributes describes the document data for the job.  For
       single-Document Jobs, they are supplied in the Print-Job or Print-URI
       requests.  For multi-Document Jobs, they are supplied in each Send-
       Document or Send-URI request.
       
       +----------------------------+----------------------+----------------+
       |      Attribute             |     Syntax           |   MANDATORY?   |
       +----------------------------+----------------------+----------------+
       | document-name              | name                 |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | document-format            | type 2 keyword       |                |
       +----------------------------+----------------------+----------------+
       | document-uri               | uri                  |                |
       +----------------------------+----------------------+----------------+
       
       6.4.1 document-name (name)
       
       This attribute contains the name of the document used by the client to
       initially identify the document. When a client prints by reference, i.e.
       includes the document-URI attribute and no document content, this
       attribute SHALL be absent.
       
       6.4.2 document-format (type2 keyword)
       
       See section 6.2.16 which describes "document-format" as a Job Template
       attribute.
       
       
       
       
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       6.4.3 document-uri (uri)
       
       This attribute contains the URI of the document when the document
       content is not included in the Send Document operation.  Document-number
       is the only other attribute allowed when a document-URI attribute is
       present in a Send Document operation.
       
       ISSUE: Now that we have Print-URI and Send-URI, do we still need this?
       Do we allow for the query of this attribute via Get-Attributes?
       
       
       6.5 Printer Description Attributes
       
       These attributes form the attribute group called "printer-description".
       A Printer object may be realized in either a print server or output
       device.  Note: How these attributes are set by an Administrator is
       outside the scope of this specification.  The following table summarizes
       these attributes, their syntax, and whether or not they are MANDATORY.
       If they are not MANDATORY, they are OPTIONAL.
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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       +----------------------------+----------------------+----------------+
       |      Attribute             |     Syntax           |   MANDATORY?   |
       +----------------------------+----------------------+----------------+
       | printer-uri                | uri                  |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | printer-uri-user           | uri                  |                |
       +----------------------------+----------------------+----------------+
       | printer-name               | name                 |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | printer-location           | text                 |                |
       +----------------------------+----------------------+----------------+
       | printer-description        | text                 |                |
       +----------------------------+----------------------+----------------+
       | printer-more-info-site     | uri                  |                |
       +----------------------------+----------------------+----------------+
       | printer-driver-installer   | uri                  |                |
       +----------------------------+----------------------+----------------+
       | printer-make-and-model     | text                 |                |
       +----------------------------+----------------------+----------------+
       | printer-more-info-         | uri                  |                |
       | manufacturer               | uri                  |                |
       +----------------------------+----------------------+----------------+
       | printer-state              | type1 keyword        |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | printer-state-reasons      | type2 keyword        |                |
       +----------------------------+----------------------+----------------+
       | printer-state-message      | text                 |                |
       +----------------------------+----------------------+----------------+
       | printer-is-accepting-jobs  | boolean              |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | queued-job-count           | integer              |                |
       +----------------------------+----------------------+----------------+
       | printer-message-from-      | text                 |                |
       | operator                   |                      |                |
       +----------------------------+----------------------+----------------+
       | printer-locale             | locale               |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | printer-locales-supported  | 1setOf locale        |  MANDATORY     |
       +----------------------------+----------------------+----------------+
       | color-supported            | boolean              |                |
       +----------------------------+----------------------+----------------+
       
       6.5.1 printer-uri (uri)
       
       This attribute contains the URI for the printer.  An administrator SHALL
       determine a printer's URI and SHALL set this attribute to that URI. The
       precise format of a printer URI SHALL be implementation dependent.
       
       
       
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       6.5.2 printer-uri-user (uri)
       
       Similar to "printer-uri", this attribute contains the URI for an HTML
       page with more information about this printer.
       
       6.5.3 printer-name (name)
       
       This attribute contains the name of the printer. It is a name that is
       more user friendly than the printer-URI. An administrator SHALL
       determine a printer's name and SHALL set this attribute to that name.
       This name may be the last part of the printer's URI or it may be
       unrelated. In non-US-English locales, a name may contain characters that
       are not allowed in a URI.
       
       6.5.4 printer-location (text)
       
       This attribute identifies the location of this printer.
       
       6.5.5 printer-description (text)
       
       This attribute identifies the descriptive information about the this
       Printer.  This could include things like: "This printer can be used for
       printing color transparencies for HR presentations", or "Out of courtesy
       for others, please print only small (1-5 page) jobs at this printer", or
       even "This printer is going away on July 1, 1997, please find a new
       printer".
       
       6.5.6 printer-more-info-site (uri)
       
       This attribute contains a URI used to obtain more information about this
       specific printer.  The information obtained from this URI is intended
       for end user consumption. Features outside the scope of IPP can be
       accessed from this URI.  The information is intended to be specific to
       this printer instance and site services (e.g. job pricing, services
       offered, end user assistance).  The printer manufacturer may initially
       populate this attribute.
       
       6.5.7 printer-driver-installer (uri)
       
       This attribute contains a URI to use to locate the driver installer for
       this printer.   This attribute is intended for consumption by automata.
       The mechanics of print driver installation is outside the scope of IPP.
       The printer manufacturer may initially populate this attribute.
       
       6.5.8 printer-make-and-model (text)
       
       This attribute identifies the make and model of the printer.
       
       
       
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       6.5.9 printer-more-info-manufacturer (uri)
       
       This attribute contains a URI used to obtain more information about this
       type of printer.  The information obtained from this URI is intended for
       end user consumption.  Features outside the scope of IPP can be accessed
       from this URI (e.g., latest firmware, upgrades, print drivers, optional
       features available).  The information is intended to be germane to this
       printer without regard to site specific modifications or services.
       
       6.5.10 printer-state (type1 keyword)
       
       This attribute identifies the current state of the printer.  The
       "printer-state reasons" attribute augments the "printer-state" attribute
       to give more detailed information about the Printer in the given printer
       state.
       
       A Printer SHALL continually keep this attribute set to the value in the
       table below which most accurately reflects the state of the Printer.  A
       Printer NEED NOT implement all values if they are not applicable to a
       given implementation.
       
       The following standard values are defined:
       
         'unknown':  The Printer state is not known, or is indeterminate. A
            Printer SHALL use this state only if it cannot determine its actual
            state.
       
         'idle':  If a Printer receives a job (whose required resources are
            ready) while in this state, such a job SHALL transit into the
            processing state immediately.  If the printer-state-reasons
            attribute contains any reasons, they SHALL be reasons that would
            not prevent a job from transiting into the processing state
            immediately, e.g., toner-low. Note: if a Printer controls more than
            one output device, the above definition implies that a Printer is
            idle if at least one output device is idle.
       
         'processing':  If a Printer receives a job (whose required resources
            are ready) while in this state, such a job SHALL transit into the
            pending state immediately. Such a job SHALL transit into the
            processing state only after jobs ahead of it complete.  If the
            printer-state-reasons attribute contains any reasons, they SHALL be
            reasons that do not prevent the current job from printing, e.g.
            toner-low.  Note: if a Printer controls more than one output
            device, the above definition implies that a Printer is processing
            if at least one output device is processing, and none is idle.
       
         'stopped':  If a Printer receives a job (whose required resources are
            ready) while in this state, such a job SHALL transit into the
       
       
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            pending state immediately. Such a job SHALL transit into the
            processing state only after some human fixes the problem that
            stopped the printer and after jobs ahead of it complete printing.
            The "printer-state-reasons" attribute SHALL contain at least one
            reason, e.g. paper-jam, which prevents it from either processing
            the current job or transiting a pending job to the processing
            state.
       
            Note: if a Printer controls more than one output device, the above
            definition implies that a Printer is stopped only if all output
            devices are stopped.  Also, it is tempting to define stopped as
            when a sufficient number of output devices are stopped and leave it
            to an implementation to define the sufficient number.  But such a
            rule complicates the definition of stopped and processing. For
            example, with this alternate definition of stopped, a job can move
            from idle to processing without human intervention, even though the
            Printer is stopped.
       
       6.5.11 printer-state-reasons (1setOf type2 keyword)
       
       This attribute supplies additional detail about the printer's state.
       
       Each MAY have an adornment to indicate its level of severity.  The three
       levels are: report (least severe), warning, and error (most severe).
       
         - 'report':  it has the adornment of "report". An implementation may
            choose to omit some or all reports. Some reports specify finer
            granularity about the printer state; others serve as a precursor to
            a warning. A report SHALL contain nothing that could affect the
            printed output.
         - 'warning': it has the adornment of "warning". An implementation may
            choose to omit some or all warnings. Warnings serve as a precursor
            to an error. A warning SHALL contain nothing that prevents a job
            from completing, though in some cases the output may be of lower
            quality.
         - 'error': it has no adornment. An implementation SHALL include all
            errors. If this attribute contains one or more errors, printer
            SHALL be in the stopped state.
       
       An implementation may add 'error-', 'warning-', or 'report-' to any of
       the reasons below to indicate the level of severity.
       
       If a Printer controls more than one output device, each value of this
       attribute SHALL apply to one or more of the output devices. An error on
       one output device that does not stop the Printer as a whole appears as a
       warning in the Printer's printer-state-reasons attribute. Such a
       Printer's printer-state value may be stopped even with no printer-state-
       reasons that are errors.
       
       
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       The following standard values are defined:
       
         'media-needed': A tray has run out of media.
         'media-jam': The printer has a media jam.
         'paused': Someone has paused the Printer. In this state, a Printer
            SHALL not produce printed output, but it SHALL perform other
            operations requested by a client. If a Printer had been printing a
            job when the Printer was paused, the Printer SHALL resume printing
            that job when the Printer is no longer paused and leave no evidence
            in the printed output of such a pause.
         'shutdown': Someone has removed a Printer from service, and it may be
            powered down or physical removed. In this state, a Printer SHALL
            not produce printed output, and unless the Printer is realized by a
            print server that is still active, the Printer SHALL perform no
            other operations requested by a client, including returning this
            value. If a Printer had been printing a job when it was shutdown,
            the Printer need not resume printing that job when the Printer is
            no longer shutdown. If the Printer resumes printing such a job, it
            may leave evidence in the printed output of such a shutdown, e.g.
            the part printed before the shutdown may be printed a second time
            after the shutdown.
       
         ISSUE: Bob suggests:  From an English point of view the suffixes
            should be -partly and -mostly rather than -report and -warning with
            all being -warnings.  For example, paused-partly-warning or media-
            needed-mostly-warning
       
         'connecting-to-device': The server has scheduled a job on the Printer
            and is in the process of connecting to a shared network output
            device (and might not be able to actually start printing the job
            for an arbitrarily long time depending on the usage of the output
            device by other servers on the network).
         'timed-out': The server was able to connect to the output device (or
            is always connected), but was unable to get a response from the
            output device.
         'stopping': The printer will be stopping in a while and will change
            its reason to printer-stopped. This reason is a non-critical, even
            for a Printer with a single output device. When an output-device
            ceases accepting jobs, the Printer will have this state while the
            output device completes printing.
         'stopped-partly': When a Printer controls more than one output
            device, this reason indicates that one or more output devices are
            stopped. If the reason is a report, fewer than half of the output
            devices are stopped. If the reason is a warning, fewer than all of
            the output devices are stopped.
         'toner-low': The Printer is low on toner.
       
       
       
       
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       6.5.12 printer-is-accepting-jobs (boolean)
       
       This attribute determines whether the printer is currently accepting
       job.  If the value is true, the printer is accepting jobs. If the value
       is false, the printer is currently rejecting any jobs submitted to it.
       
       Note: This value is independent of the printer state and printer-state-
       reasons because its value does not affect the current job; rather it
       affects future jobs. This attribute may cause the Printer to reject jobs
       when the printer-state is idle or it may cause the Printer to accepts
       jobs when the printer-state is stopped.
       
       6.5.13 printer-state-message (text)
       
       This attribute specifies the additional information about the printer
       state in human readable text and it SHALL be set by the Printer (or the
       Administrator by some mechanism outside the scope of IPP). When a
       Printer returns the value of this attribute to a client, the Printer
       SHALL localize the value of this attribute to be in the locale of the
       user, as specified by the Get-Attributes or Get-Jobs operation.
       
       6.5.14 queued-job-count (integer(0:2**31 - 1))
       
       This attribute contains a count of the number of jobs that are either
       pending and/or processing and SHALL be set by the Printer.
       
       6.5.15 printer-message-from-the-operator (text)
       
       This attribute provides a message from an operator, system administrator
       or "intelligent" process to indicate to the end user information or
       status of the printer, such as why it is unavailable or when it is
       expected to be available.
       
       6.5.16 printer-locale (locale)
       
       This attribute specifies the current locale that the Printer is
       operating in.
       
       6.5.17 printer-locales-supported (1setOf locale)
       
       This attribute specifies the locales that the Printer operates in.
       
       6.5.18 color-supported (boolean)
       
       This attribute identifies whether the Printer is capable of any type of
       color printing at all.  All document instructions having to do with
       color are embedded within the document PDL (none are external IPP
       attributes).
       
       
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       7. Conformance
       
       This section describes conformance issues and requirements. This
       document introduces model entities such as objects, operations,
       attributes, and attribute values.  These conformance sections describe
       the conformance requirements which apply to these model entities.
       
       
       7.1 Conditionally Mandatory
       
       For example, a conditionally mandatory attribute means that a Printer
       implementation need not support the attribute if the attribute controls
       a feature that the output device does not implement or expose.  For
       example, for an output device that can only print on one side, a Printer
       need not support the "sides" attribute.  For an output device that does
       not support any of the finishing attribute values, a Printer need not
       support the "finishing" attribute.
       
       
       7.2 Client Conformance Requirements
       
       There are no conformance requirements placed on the user interfaces
       provided by IPP clients or their applications.  For example, one
       application might not allow an end user to submit multiple documents per
       job, while another does.  One application might first query a Printer
       object in order to supply a graphical user interface (GUI) dialogue box
       with supported and default values whereas a different implementation
       might not.
       
       When sending a Get-Attributes or create request, an IPP client need not
       supply any attributes.
       
       A client SHALL be able to accept any of the attribute syntaxes defined
       in Section 6.1 that may be returned to it in a response from a Printer
       
       A query response may contain attributes and values that the client does
       not expect.  Therefore, a client implementation MUST gracefully handle
       such responses and not refuse to interoperate with a conforming Printer
       that is returning extended registered or private attributes and/or
       attribute values that conform to Section 8.  Clients may choose to
       ignore any attributes that it does not understand.
       
       
       7.3 Printer Object Conformance Requirements
       
       This section specifies the conformance requirements for conforming
       Printer object implementations with respect to objects, operations, and
       attributes.
       
       
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       7.3.1 Objects
       
       Conforming Printer implementations SHALL implement all of the model
       objects as defined in this specification in the indicated sections:
       
         Section 4.1 Printer Object
         Section 4.2 Job Object
         Section 4.3 Document Object
       
       7.3.2 Operations
       
       Conforming Printer implementations SHALL implement all of the MANDATORY
       model operations, including mandatory responses, as defined in this
       specification in the indicated sections:
       
         For a Printer object:
            Get-Operations (section 5.1.1)               MANDATORY
            Print-Job (section 5.1.2)                    MANDATORY
            Print-URI (section 5.1.3)                    OPTIONAL
            Validate-Job (section 5.1.4)                 OPTIONAL
            Create-Job (section 5.1.5)                   OPTIONAL
            Get-Jobs (section 5.1.8)                OPTIONAL
            Get-Attributes (section 5.1.9)                    OPTIONAL
       
         For a Job object:
            Send-Document (section 5.1.6)           OPTIONAL
            Send-URI (section 5.1.7)                OPTIONAL
            Cancel-Job (section 5.1.8)                   MANDATORY
            Get-Attributes (section 5.1.9)                    OPTIONAL
       
       7.3.3 Attributes
       
       ISSUE:  Some Printer attributes are purely software, so that
       Conditionally Mandatory doesn't apply, such as Printer Description
       Attributes.  For example, what does it mean for the "printer-location"
       to be Conditionally Mandatory?  Should we add a "OPTIONAL" in the header
       of the few attributes for which Conditionally Mandatory doesn't make
       sense?
       
       Conforming Printer implementations SHALL support all of the MANDATORY
       attributes, as defined in this specification in the indicated sections.
       
       Conforming Printer implementations SHALL support all CONDITIONALLY
       MANDATORY attributes as defined in this specification in the indicated
       sections that represent features and behaviors that the actual output
       device implements.
       
       
       
       
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       It is not required that a conforming Printer support all values of all
       supported attributes.  For example, if a Printer supports some of the
       "finishing" attribute values in this document, it is not required that a
       Printer implement or support all finishing methods indicated by all the
       values of the "finishing" attribute contained in this document.
       
       If a Printer implements a "xxx-supported" attribute it MUST implement
       the corresponding "xxx" default value attribute and vice versa.
       
       7.3.4 Printer extensions
       
       A conforming Printer may support registered extensions and private
       extensions, as long as they meet the requirements specified in Section
       8.
       
       7.3.5 Attribute Syntaxes
       
       A Printer SHALL be able to accept any of the attribute syntaxes defined
       in Section 6.1 in any operation in which a client may supply attributes.
       Furthermore, a Printer SHALL return attributes to the client in
       operation responses that conform to the syntax specified in Section 6.1.
       
       
       7.4 Security Conformance Requirements
       
       The security mechanisms being considered for IPP fall outside the scope
       of the application layer protocol itself.  There are two mechanisms used
       to begin secure communications using IPP:
       
         1. Information in the directory entry for an IPP Printer (or from
            additional information at a Web site hosting the IPP Printer)
            indicate which, if any, security protocols are used in conjunction
            with IPP.
       
         2. The URI for the IPP Printer contains the security protocol
            information (https://..., etc.).
       
       In either case, the security protocol (if any) is initiated first which
       allows for the negotiation of security features.  IPP is then run as an
       application protocol on top of the security protocols.  One cannot
       "bootstrap" the security features from IPP itself.
       
       ISSUE: The above is not quite correct.  Waiting for better description
       from the security document [22].
       
       
       
       
       
       
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       8. IANA Considerations, Registered Extensions, Private Extensions
       
       IPP is explicitly designed to be extensible.  Additional attributes can
       be proposed to be registered by going through the type 2 or type 3
       keyword process which will register their specification after approval
       with IANA.  In addition specific implementation instances may support
       not only the basic protocol as defined in this specification, but may
       add vendor-specific private extensions by prefixing attribute-names with
       their company name registered with IANA for use in domains.  See
       attribute syntax section.  However, such private extensions SHALL not
       duplicate attribute semantics already in this specification.
       
       
       9. Security Considerations
       
       There is another Internet-Draft called "Internet Printing Protocol/1.0:
       Security" [22].  That document is being drafted and reviewed in parallel
       with this document.  The mapping of IPP on top of appropriate security
       protocols will be described in that document.  IPP does not introduce
       any new, general purpose security mechanisms for authentication and
       encryption.
       
       A Printer may choose, for security reasons, not to return all attributes
       that a client requests. It may even return none of the requested
       attributes. In such cases, the status returned is the same as if the
       Printer had returned all requested attributes. The client cannot tell by
       such a response whether the requested attribute was present or absent on
       the Printer.
       
       
       10. References
       
       [1]  Smith, R., Wright, F., Hastings, T., Zilles, S., and Gyllenskog,
            J., "Printer MIB", RFC 1759, March 1995.
       
       [2]  Berners-Lee, T, Fielding, R., and Nielsen, H., "Hypertext Transfer
            Protocol - HTTP/1.0", RFC 1945, August 1995.
       
       [3]  Crocker, D., "Standard for the Format of ARPA Internet Text
            Messages", RFC 822, August 1982.
       
       [4]  Postel, J., "Instructions to RFC Authors", RFC 1543, October 1993.
       
       [5]  ISO/IEC 10175 Document Printing Application (DPA), June 1996.
       
       [6]  Herriot, R. (editor), X/Open A Printing System Interoperability
            Specification (PSIS), August 1995.
       
       
       
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       [7]  Kirk, M. (editor), POSIX System Administration - Part 4: Printing
            Interfaces, POSIX 1387.4 D8, 1994.
       
       [8]  Borenstein, N., and Freed, N., "MIME (Multi-purpose Internet Mail
            Extensions) Part One: Mechanism for Specifying and Describing the
            Format of Internet Message Bodies", RFC 1521, September, 1993.
       
       [9]  Braden, S., "Requirements for Internet Hosts - Application and
            Support", RFC 1123, October, 1989,
       
       [10] McLaughlin, L. III, (editor), "Line Printer Daemon Protocol" RFC
            1179, August 1990.
       
       [11] Berners-Lee, T., Masinter, L., McCahill, M. , "Uniform Resource
            Locators (URL)", RFC 1738, December, 1994.
       
        [20]     Internet Printing Protocol: Requirements
       
       [21] Internet Printing Protocol/1.0: Model and Semantics (This document)
       
       [22] Internet Printing Protocol/1.0: Security
       
       [23] Internet Printing Protocol/1.0: Protocol Specification
       
       [24] Internet Printing Protocol/1.0: Directory Schema
       
       [25] S. Bradner, "Key words for use in RFCs to Indicate Requirement
            Levels", RFC 2119 , March 1997
       
       [26] H. Alvestrand, " Tags for the Identification of Languages", RFC
            1766, March 1995.
       
       
       
       
       11. Author's Address
       
            Scott A. Isaacson
            Novell, Inc.
            122 E 1700 S
            Provo, UT   84606
       
            Phone: 801-861-7366
            Fax:   801-861-4025
            EMail: scott_isaacson@novell.com
       
            Tom Hastings
            Xerox Corporation
       
       
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            701 S. Aviation Blvd.
            El Segundo, CA   90245
       
            Phone: 310-333-6413
            Fax:   310-333-5514
            EMail: hastings@cp10.es.xerox.com
       
            Robert Herriot
            Sun Microsystems Inc.
            2550 Garcia Ave., MPK-17
            Mountain View, CA 94043
       
            Phone: 415-786-8995
            Fax:  415-786-7077
            Email: robert.herriot@eng.sun.com
       
            Roger deBry
            HUC/003G
            IBM Corporation
            P.O. Box 1900
            Boulder, CO 80301-9191
       
            Phone: (303) 924-4080
            Fax: (303) 924-9889
            Email: debry@vnet.ibm.com
       
            Patrick Powell
            San Diego State University
            9475 Chesapeake Dr., Suite D
            San Diego, CA  95123
       
            Phone: (619) 874-6543
            Fax: (619) 279-8424
            Email: papowell@sdsu.edu
       
            IPP Mailing List:  ipp@pwg.org
            IPP Mailing List Subscription:  ipp-request@pwg.org
            IPP Web Page:  http://www.pwg.org/ipp/
       
         Other Participants:
       
            Chuck Adams - Tektronix
            Jeff Barnett - IBM
            Ron Bergman - Data Products
            Keith Carter, IBM Corporation
            Jeff Copeland - QMS
            Andy Davidson - Tektronix
            Mabry Dozier - QMS
       
       
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            Lee Farrell - Canon Information Systems
            Steve Gebert - IBM
            David Kellerman - Northlake Software
            Rick Landau - Digital
            Harry Lewis - IBM
            Pete Loya - HP
            Ray Lutz - Cognisys
            Mike MacKay, Novell, Inc.
            Carl-Uno Manros, Xerox, Corp.
            Jay Martin - Underscore
            Stan McConnell - Xerox
            Pat Nogay - IBM
            Bob Pentecost - HP
            Rob Rhoads - Intel
            David Roach - Unisys
            Hiroyuki Sato - Canon
            Bob Setterbo - Adobe
            Devon Taylor, Novell, Inc.
            Mike Timperman - Lexmark
            Randy Turner - Sharp
            Atsushi Yuki - Kyocera
            Lloyd Young - Lexmark
            Bill Wagner - DPI
            Jim Walker - DAZEL
            Chris Wellens - Interworking Labs
            Rob Whittle - Novell
            Don Wright - Lexmark
            Peter Zehler, Xerox, Corp.
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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       12. APPENDIX A - Status Codes
       
       The Status keyword provides information on the results of a request. The
       Message provides a short textual description of the Status. The Status
       is intended for use by automata and the Message is intended for the
       human user.  An IPP application (i.e. a browser, GUI, print driver or
       gateway) is not required to examine or display the Message.
       
       The prefix of the Status keyword defines the class of response as
       follows:
       
         informational - Request received, continuing process
       
         successful - The action was successfully received, understood, and
            accepted
       
         redirection - Further action must be taken in order to complete the
            request
       
         client-error - The request contains bad syntax or cannot be fulfilled
       
         server-error - The server failed to fulfill an apparently valid
            request
       
       IPP status codes are extensible.  IPP applications are not required to
       understand the meaning of all registered status codes, though such
       understanding is obviously desirable.  However, applications shall
       understand the class of any status code, as indicated by the prefix, and
       treat any unrecognized response as being equivalent to the first  status
       code of that class, with the exception that an unrecognized response
       shall not be cached.  For example, if an unrecognized status  code of
       client-error-foo-bar is received by the client, it can safely assume
       that there was something wrong with its request and treat the response
       as if it had received a client-error-bad-request status code.  In such
       cases, IPP applications should present the Message to the user, since
       that Message is likely to include human-readable information which will
       explain the unusual status.
       
       
       12.1 Status Codes (type2 keyword)
       
       Each Status is described below, including a description of which
       operation(s) it can follow and any metainformation required in the
       response.
       
       
       
       
       
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       12.1.1 Informational
       
       This class of status code indicates a provisional response and is to be
       used for informational purposes only.  There are no status codes defined
       in IPP 1.0 for this class of status code.
       
       12.1.2 Successful Status Codes
       
       This class of status code indicates that the client's request was
       successfully received, understood, and accepted.
       
       12.1.2.1 successful-OK (IPPL1)
       
       The request has succeeded.
       
       Note:  IPPL1 only includes OK.  IPPL1 does not include Created nor No
       Content successful status codes.  This is consistent with our agreement
       at the IPP Model telecon on May 9, but I believe we had this discussion
       before Bob Herriot joined the telecon.
       
       12.1.3 Redirection Status Codes
       
       This class of status code indicates that further action needs to be
       taken to fulfill the request.  There are no status codes defined in IPP
       1.0 for this class of status code.
       
       12.1.4 Client Error Status Codes
       
       This class of status code is intended for cases in which the client
       seems to have erred.  The server should return a Message containing an
       explanation of the error situation and whether it is a temporary or
       permanent condition.  IPP applications should display any returned
       Message to the end-user.  Unless otherwise noted, these status codes
       apply to all operations.
       
       12.1.4.1 client-error-bad-request (IPPL1)
       
       The request could not be understood by the server due to malformed
       syntax.  The IPP application should not repeat the request without
       modifications.
       
       12.1.4.2 client-error-unauthorized
       
       The request requires user authentication.  The IPP client may repeat the
       request with suitable authorization credentials. If the request already
       included authorization credentials, then this status code indicates that
       authorization has been refused for those credentials.  If this response
       contains the same challenge as the prior response, and the user agent
       
       
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       has already attempted authentication at least once, then the user should
       be presented the Message in the response, since that Message may include
       relevant diagnostic information.
       
       12.1.4.3 client-error-payment-required
       
       This request requires payment by the end-user to perform the operation.
       
       12.1.4.4 client-error-forbidden (IPPL1)
       
       The server understood the request, but is refusing to fulfill it.
       Authorization will not help and the request should not be repeated.
       This status code is commonly used when the server does not wish to
       reveal exactly why the request has been refused or when no other
       response is applicable.
       
       12.1.4.5 client-error-method-not-allowed
       
       The operation specified in the request is not allowed for the object
       identified by the request URI.
       
       12.1.4.6 client-error-timeout (NEW)
       
       The client did not produce a request within the time that the server was
       prepared to wait.  The client MAY repeat the request without
       modifications at any later time.
       
       12.1.4.7 client-error-not-found
       
       The server has not found anything matching the request URI.  No
       indication is given of whether the condition is temporary or permanent.
       
       In practice, an application should avoid this situation by presenting a
       list of valid Printer URIs and Job URIs to the end-user.
       
       12.1.4.8 client-error-gone
       
       The requested object is no longer available at the server and no
       forwarding address is known.  This condition should be considered
       permanent.  Clients with link editing capabilities should delete
       references to the request URI after user approval.  If the server does
       not know or has no facility to determine,whether or not the condition is
       permanent, the status code client-error-not-found should be used
       instead.  This response is cachable unless indicated otherwise.
       
       This response is primarily intended to assist the task of web
       maintenance by notifying the recipient that the resource is
       intentionally unavailable and that the server owners desire that remote
       
       
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       links to that resource be removed.  Such an event is common for limited-
       time, promotional services and for resources belonging to individuals no
       longer working at the server's site.  It is not necessary to mark all
       permanently unavailable resources as "gone" or to keep the mark for any
       length of time -- that is left to the discretion of the server owner.
       
       12.1.4.9 client-error-request-entity-too-large (IPPL1)
       
       The server is refusing to process a request because the request entity
       is larger than the server is willing or able to process.  An IPP Printer
       returns this status code when it limits the size of print jobs and it
       receives a print job that exceeds that limit.
       
       12.1.4.10 client-error-request-URI-too-long
       
       The server is refusing to service the request because the request URI is
       longer than the server is willing to interpret.  This rare condition is
       only likely to occur when a client has improperly submitted a request
       with long query information (e.g. an IPP application allows an end-user
       to enter an invalid URI), when the client has descended into a URL
       "black hole" of redirection (e.g., a redirected URL prefix that points
       to a suffix of itself), or when the server is under attack by a client
       attempting to exploit security holes present in some servers using
       fixed-length buffers for reading or manipulating the Request-URI.
       
       12.1.4.11 client-error-unsupported-media-type (IPPL1)
       
       The server is refusing to service the request because the print data is
       in a format, as specified in document-format, not supported by the IPP
       Printer.
       
       12.1.4.12 client-error-attribute-value-not-supported
       
       For a Create-Job, Print-Job or Validate operation, if the IPP Printer
       does not support at least one attribute value specified in the request,
       the Printer shall return this status.  For example, if the request
       requires A4 paper and that paper size is not supported by the Printer,
       the Printer shall return this status.
       
       For a Get-Jobs operation, if the IPP Printer does not support at least
       one attribute value for Job Owner and/or Job States in the request, the
       Printer shall return this status.
       
       In practice, an IPP application should avoid this situation by querying
       an IPP Printer for its valid attributes and values before performing an
       operation on the Printer.
       
       
       
       
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       12.1.5 Server Error Status Codes
       
       This class of status codes indicates cases in which the server is aware
       that it has erred or is incapable of performing the request.  The server
       should include a Message containing an explanation of the error
       situation, and whether it is a temporary or permanent condition. IPP
       applications should display any included Message to the user. These
       response codes are applicable to any operation.
       
       12.1.5.1 server-error-internal-server-error
       
       The server encountered an unexpected condition which prevented it from
       fulfilling the request.
       
       12.1.5.2 server-error-operation-not-implemented
       
       The server does not support the functionality required to fulfill the
       request. This is the appropriate response when the server does not
       recognize an operation and is not capable of supporting it for any
       object.
       
       12.1.5.3 server-error-service-unavailable
       
       The server is currently unable to handle the request due to a temporary
       overloading or maintenance of the server.  The implication is that this
       is a temporary condition which will be alleviated after some delay. If
       known, the length of the delay may be indicated in the Message.  If no
       delay is given, the IPP application should handle the response as it
       would for a server-error-internal-server-error response.
       
       12.1.5.4 server-error-timeout (NEW)
       
       The server did not produce a response within the time that the client
       was prepared to wait.  The client MAY repeat the request without
       modifications at any later time.
       
       12.1.5.5 server-error-HTTP-version-not-supported (NEW)
       
       The server does not support, or refuses to support, the HTTP protocol
       version that was used in the request message.  The server is indicating
       that it is unable or unwilling to complete the request using the same
       major version as the client other than with this error message.  The
       response SHOULD contain a message describing why the version is not
       supported and what other protocols are supported by that server.
       
       
       
       
       
       
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       12.1.5.6 server-error-IPP-version-not-supported
       
       The server does not support, or refuses to support, the IPP protocol
       version that was used in the request message. The server is indicating
       that it is unable or unwilling to complete the request using the same
       major  version as the client other than with this error message. The
       response should contain a Message describing why that version is not
       supported and what other versions are supported by that server.
       
       A conforming IPP client shall specify the valid version for IPP 1.0 on
       each request.  A conforming IPP server shall not return this status code
       to a conforming IPP 1.0 client.  An IPP server shall return this status
       code to a non-conforming IPP client.
       
       12.1.5.7 server-error-printer-error
       
       A printer error, such as a paper jam, occurs while the IPP Printer
       processes a Print or Send operation.  The response shall contain the Job
       Status with the specific error and should contain a Message describing
       the error.  An IPP application should check the Job Status in the
       response for the specific error.
       
       12.1.5.8 server-error-write-fault
       
       A write error, such as a memory overflow (i.e. the document data exceeds
       the memory of the Printer) or a disk full condition, occurs while the
       IPP Printer processes a Print or Send operation.
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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       12.2 Mapping of HTTP 1.1 Status Codes to IPP Status Keywords
       
       HTTP 1.1 Status                    IPP Keyword
       ---------------                    -----------
       100 Continue                       none
       101 Switching Protocols            none
       200 OK                             successful-OK
       201 Created                        successful-OK
       202 Accepted                       successful-OK
       203 Non-Authoritive Information    successful-OK
       204 No Content                     successful-OK
       205 Reset Content                  none
       206 Partial Content (GET)          none
       300 Multiple Choices               none
       301 Moved Permanently              none
       302 Moved Temporarily              none
       303 See Other                      none
       304 Not Modified (GET)             none
       305 Use Proxy                      none
       400 Bad Request                    client-error-bad-request
       401 Unauthorized                   client-error-unauthorized
       402 Payment Required               client-error-payment-required
       403 Forbidden                      client-error-forbidden
       404 Not Found                      client-error-not-found
       405 Method Not Allowed             client-error-method-not-allowed
       406 Not Acceptable                 client-error-bad-request
       407 Proxy Authentication Required  client-error-unauthorized
       408 Request Timeout                client-error-timeout
       409 Conflict (most likely PUT)     client-error-bad-request
       410 Gone                           client-error-gone
       411 Length Required                client-error-bad-request
       412 Precondition Failed            client-error-bad-request
       413 Request Entity Too Large       client-error-request-entity-
                                               too-large
       414 Request-URI Too Long           client-error-request-URI-too-long
       415 Unsupported Media Type         client-error-unsupported-media-
                                               type
       none                               client-error-attribute-value-
                                               not-supported
       500 Internal Server Error          server-error-internal-server-error
       501 Not Implemented                server-error-not-implemented
       502 Bad Gateway                    server-error-internal-server-error
       503 Service Unavailable            server-error-service-unavailable
       504 Gateway Timeout                server-error-timeout
       505 HTTP Version Not Supported     server-error-HTTP-version-
                                               not-supported
       none                               server-error-IPP-version-
                                               not-supported
       
       
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       none                               server-error-printer-error
       none                               server-error-write-fault
       
       
       
       12.3 Status Keywords for IPP Operations
       
       PJ = Print-Job, PU = Print-URI, CJ = Create-Job, SD = Send-Document
       SU = Send-URI, V = Validate, GA = Get-Attributes, GJ = Get-Jobs
       GO = Get-Operations, C = Cancel-Job
       
                                                      IPP Operations
       IPP Status Keyword                       PJ PU CJ SD SU V GA GJ GO C
       ------------------                       -- -- -- -- -- - -- -- -- -
       successful-OK                            x  x  x  x  x  x x  x  x  x
       client-error-bad-request                 x  x  x  x  x  x x  x  x  x
       client-error-unauthorized                x  x  x  x  x  x x  x  x  x
       client-error-payment-required            x  x  x  x  x  x
       client-error-forbidden                   x  x  x  x  x  x x  x  x  x
       client-error-not-found                   x  x  x  x  x  x x  x  x  x
       client-error-method-not-allowed          x  x  x  x  x  x x  x  x  x
       client-error-timeout                     x  x  x  x  x  x x  x  x  x
       client-error-gone                        x  x  x  x  x  x x  x  x  x
       client-error-request-entity-too-large    x        x
       client-error-request-URI-too-long        x  x  x  x  x  x x  x  x  x
       client-error-unsupported-media-type      x  x     x  x
       client-error-attribute-value-not-        x  x  x        x
            supported
       server-error-internal-server-error       x  x  x  x  x  x x  x  x  x
       server-error-service-unavailable         x  x  x  x  x  x x  x  x  x
       server-error-timeout                     x  x  x  x  x  x x  x  x  x
       server-error-HTTP-version-not-supported  x  x  x  x  x  x x  x  x  x
       server-error-IPP-version-not-supported   x  x  x  x  x  x x  x  x  x
       server-error-printer-error               x  x  x  x  x
       server-error-write-fault                 x  x  x  x  x
       
       
       13. APPENDIX B - "document-format" Values
       
       The Printer Working Group has registered a set of values with IANA as
       part of the IETF Printer MIB project.  The standard value assigned by
       the PWG starts with the four letters: "lang", in order to follow SNMP
       ASN.1 rules that all enum symbols SHALL start with a lower case letter.
       The keyword values in IPP is the same as the PWG standard values
       registered with IANA with the "lang" removed.  The MIB (integer) value
       is included here for reference only, the MIB integer value SHALL NOT be
       used in IPP; the keyword value SHALL be used.  In the IPP Protocol
       Specification [22], the keyword value SHALL be encoded as a MIME type.
       
       
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       The standard values are:
       
         'other': 1 -
         'PCL': 3 - PCL.  Starting with PCL version 5, HP-GL/2 is included as
            part of the PCL language.  PCL and HP-GL/2 are registered
            trademarks of Hewlett-Packard Company.
         'HPGL': 4 - Hewlett-Packard Graphics Language.  HP-GL is a registered
            trademark of Hewlett-Packard Company.
         'PJL': 5 - Peripheral Job Language.  Appears in the data stream
            between data intended for a page description language.  Hewlett-
            Packard Co.
         'PS': 6 - PostScript Language (tm) Postscript - a trademark of Adobe
            Systems Incorporated which may be registered in certain
            jurisdictions
         'IPDS': 7 - Intelligent Printer Data Stream Bi-directional print data
            stream for documents consisting of data objects (text, image,
            graphics, bar codes), resources (fonts, overlays) and page, form
            and finishing instructions.  Facilitates system level device
            control, document tracking and error recovery throughout the print
            process.  Pennant Systems, IBM
         'PPDS': 8 - IBM Personal Printer Data Stream.  Originally called IBM
            ASCII, the name was changed to PPDS when the Laser Printer was
            introduced in 1989.  Lexmark International, Inc.
         'EscapeP': 9 - Epson Corp.
         'Epson': 10 -
         'DDIF': 11 - Digital Document Interchange Format Digital Equipment
            Corp., Maynard MA
         'Interpress': 12 - Xerox Corp.
         'ISO6429': 13 - ISO 6429.  Control functions for Coded Character Sets
            (has ASCII control characters, plus additional controls for
            character imaging devices.) ISO Standard, Geneva, Switzerland
         'LineData': 14 - line-data: Lines of data as separate ASCII or EBCDIC
            records and containing no control functions (no CR, LF, HT, FF,
            etc.).  For use with traditional line printers.  May use CR and/or
            LF to delimit lines, instead of records.  See ISO 10175 Document
            Printing Application (DPA) ISO standard, Geneva, Switzerland
         'MODCA': 15 - Mixed Object Document Content Architecture Definitions
            that allow the composition, interchange, and presentation of final
            form documents as a collection of data objects (text, image,
            graphics, bar codes), resources (fonts, overlays) and page, form
            and finishing instructions.  Pennant Systems, IBM
         'REGIS': 16 - Remote Graphics Instruction Set, Digital Equipment
            Corp., Maynard MA
         'SCS': 17 - SNA Character String Bi-directional print data stream for
            SNA LU-1 mode of communications IBM
         'SPDL': 18 - ISO 10180 Standard Page Description Language ISO
            Standard
         'TEK4014': 19 - Tektronix Corp.
       
       
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         'PDS': 20 -
         'IGP': 21 - Printronix Corp.
         'CodeV': 22 - Magnum Code-V, Image and printer control language used
            to control impact/dot- matrix printers.  QMS, Inc., Mobile AL
         'DSCDSE': 23 - DSC-DSE: Data Stream Compatible and Emulation Bi-
            directional print data stream for non-SNA (DSC) and SNA LU-3 3270
            controller (DSE) communications IBM
         'WPS': 24 - Windows Printing System, Resource based command/data
            stream used by Microsoft At Work Peripherals.  Developed by the
            Microsoft Corporation.
         'LN03': 25 - Early DEC-PPL3, Digital Equipment Corp.
         'CCITT': 26 -
         'QUIC': 27 - QUIC (Quality Information Code), Page Description
            Language for laser printers.  Included graphics, printer control
            capability and emulation of other well- known printer .  QMS, Inc.
         'CPAP': 28 - Common Printer Access Protocol Digital Equipment Corp
         'DecPPL': 29 - Digital ANSI-Compliant Printing Protocol (DEC-PPL)
            Digital Equipment Corp
         'SimpleText': 30 - simple-text: character coded data, including NUL,
            CR , LF, HT, and FF control characters.  See ISO 10175 Document
            Printing Application (DPA) ISO standard, Geneva, Switzerlan
         'NPAP': 31 - Network Printer Alliance Protocol (NPAP).  This protocol
            has been superseded by the IEEE 1284.1 TIPSI standard.  (ref.
            LangTIPSI(49)).
         'DOC': 32 - Document Option Commands, Appears in the data stream
            between data intended for a page description .  QMS, Inc
         'imPress': 33 - imPRESS, Page description language originally
            developed for the ImageServer line of systems.  A binary language
            providing representations for text, simple graphics (rules, lines,
            conic sections), and some large forms (simple bit-map and CCITT
            group 3/4 encoded).The language was intended to be sent over an 8-
            bit channel and supported early document preparation languages
            (e.g.  TeX and TROFF).  QMS, Inc.
         'Pinwriter': 34 - 24 wire dot matrix printer for USA, Europe, and
            Asia except Japan.  More widely used in Germany, and some Asian
            countries than in US.  NEC
         'NPDL': 35 - Page printer for Japanese market.  NEC
         'NEC201PL': 36 - Serial printer language used in the Japanese market.
            NEC
         'Automatic': 37 - Automatic PDL sensing.  Automatic sensing of the
            interpreter language family by the printer examining the document
            content.  Which actual interpreter language families are sensed
            depends on the printer implementation.
         'Pages': 38 - Page printer Advanced Graphic Escape Set IBM Japan
         'LIPS': 39 - LBP Image Processing System
         'TIFF': 40 - Tagged Image File Format (Aldus)
         'Diagnostic': 41 - A hex dump of the input to the interpreter
       
       
       
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         'PSPrinter': 42 - The PostScript Language used for control (with any
            PDLs) Adobe Systems Incorporated
         'CaPSL': 43 - Canon Print Systems Language
         'EXCL': 44 - Extended Command Language Talaris Systems Inc
         'LCDS': 45 - Line Conditioned Data Stream Xerox Corporatio
         'XES': 46 - Xerox Escape Sequences Xerox Corporation
         'PCLXL': 47 - Printer Control Language.  Extended language features
            for printing, and printer control.  Technical reference manual #
            TBD.  Hewlett-Packard Co.
         'ART': 48 - Advanced Rendering Tools (ART).  Page Description
            language originally developed for the Laser Press printers.
            Tehnical reference manual: "ART IV Reference Manual", No F33M.
            Fuji Xerox Co., Ltd.
         'TIPSI': 49 - Transport Independent Printer System Interface (ref.
            IEEE Std.  1284.1)
         'Prescribe': 50 - Page description and printer control language.  It
            can be described with ordinary ASCII characters.  Technical
            reference manual: "PRESCRIBE II Programming Manual"
         'LinePrinter': 51 - A simple-text character stream which supports the
            control codes LF, VT, FF and CR plus Centronics or Dataproducts
            Vertical Format Unit (VFU).  language is commonly used on many
            older model line and matrix printers.
         'IDP': 52 - Imaging Device Protocol Apple Computer.
         'XJCL': 53 - Xerox Corp.
       
       
       One special value is 'auto-sense'.  However a client SHALL NOT supply
       the value 'auto-sense' in a create request.  If the "document-format" is
       unknown for a certain document, the client SHALL NOT supply the
       attribute in the create request or the Send-Document Request.
       
       
       14. APPENDIX C - "media" Values
       
       Standard values are taken from several sources.
       
       Standard values are defined(taken from ISO DPA and the Printer MIB):
       
         'default': The default medium for the output device
         'iso-a4-white': Specifies the ISO A4 white medium
         'iso-a4-colored': Specifies the ISO A4 coloured medium
         'iso-a4-transparent' Specifies the ISO A4 transparent medium
         'iso-a3-white': Specifies the ISO A3 white medium
         'iso-a3-colored': Specifies the ISO A3 coloured medium
         'iso-a5-white': Specifies the ISO A5 white medium
         'iso-a5-colored': Specifies the ISO A5 coloured medium
         'iso-b4-white': Specifies the ISO B4 white medium
         'iso-b4-colored': Specifies the ISO B4 coloured medium
       
       
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         'iso-b5-white': Specifies the ISO B5 white medium
         'iso-b5-colored': Specifies the ISO B5 coloured medium
         'jis-b4-white': Specifies the JIS B4 white medium
         'jis-b4-colored': Specifies the JIS B4 coloured medium
         'jis-b5-white': Specifies the JIS B5 white medium
         'jis-b5-colored': Specifies the JIS B5 coloured medium
       
       
       The following standard values are defined for North American media:
       
         'na-letter-white': Specifies the North American letter white medium
         'na-letter-colored': Specifies the North American letter coloured
            medium
         'na-letter-transparent': Specifies the North American letter
            transparent medium
         'na-legal-white': Specifies the North American legal white medium
         'na-legal-colored': Specifies the North American legal coloured
            medium
       
       
       The following standard values are defined for envelopes:
       
         'iso-b4-envelope': Specifies the ISO B4 envelope medium
         'iso-b5-envelope': Specifies the ISO B5 envelope medium
         'iso-c3-envelope': Specifies the ISO C3 envelope medium
         'iso-c4-envelope': Specifies the ISO C4 envelope medium
         'iso-c5-envelope': Specifies the ISO C5 envelope medium
         'iso-c6-envelope': Specifies the ISO C6 envelope medium
         'iso-designated-long-envelope': Specifies the ISO Designated Long
            envelope medium
         'na-10x13-envelope': Specifies the North American 10x13 envelope
            medium
         'na-9x12-envelope': Specifies the North American 9x12 envelope medium
         'monarch-envelope': Specifies the Monarch envelope
         'na-number-10-envelope': Specifies the North American number 10
            business envelope medium
         'na-7x9-envelope': Specifies the North American 7x9 inch envelope
         'na-9x11-envelope': Specifies the North American 9x11 inch envelope
         'na-10x14-envelope': Specifies the North American 10x14 inch envelope
         'na-number-9-envelope': Specifies the North American number 9
            business envelope
         'na-6x9-envelope': Specifies the North American 6x9 inch envelope
         'na-10x15-envelope': Specifies the North American 10x15 inch envelope
       
       
       The following standard values are defined for the less commonly used
       media (white-only):
       
       
       
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         'executive-white': Specifies the white executive medium
         'folio-white': Specifies the folio white medium
         'invoice-white': Specifies the white invoice medium
         'ledger-white': Specifies the white ledger medium
         'quarto-white': Specified the white quarto medium
         'iso-a0-white': Specifies the ISO A0 white medium
         'iso-a1-white': Specifies the ISO A1 white medium
         'iso-a2-white': Specifies the ISO A2 white medium
         'iso-a6-white': Specifies the ISO A6 white medium
         'iso-a7-white': Specifies the ISO A7 white medium
         'iso-a8-white': Specifies the ISO A8 white medium
         'iso-a9-white': Specifies the ISO A9 white medium
         'iso-10-white': Specifies the ISO A10 white medium
         'iso-b0-white': Specifies the ISO B0 white medium
         'iso-b1-white': Specifies the ISO B1 white medium
         'iso-b2-white': Specifies the ISO B2 white medium
         'iso-b3-white': Specifies the ISO B3 white medium
         'iso-b6-white': Specifies the ISO B6 white medium
         'iso-b7-white': Specifies the ISO B7 white medium
         'iso-b8-white': Specifies the ISO B8 white medium
         'iso-b9-white': Specifies the ISO B9 white medium
         'iso-b10-white': Specifies the ISO B10 white medium
         'jis-b0-white': Specifies the JIS B0 white medium
         'jis-b1-white': Specifies the JIS B1 white medium
         'jis-b2-white': Specifies the JIS B2 white medium
         'jis-b3-white': Specifies the JIS B3 white medium
         'jis-b6-white': Specifies the JIS B6 white medium
         'jis-b7-white': Specifies the JIS B7 white medium
         'jis-b8-white': Specifies the JIS B8 white medium
         'jis-b9-white': Specifies the JIS B9 white medium
         'jis-b10-white': Specifies the JIS B10 white medium
       
       
       The following standard values are defined for engineering media:
       
         'a': Specifies the engineering A size medium
         'b': Specifies the engineering B size medium
         'c': Specifies the engineering C size medium
         'd': Specifies the engineering D size medium
         'e': Specifies the engineering E size medium
       
       
       The following standard values are defined for input-trays (from ISO DPA
       and the Printer MIB):
       
         'top': The top input tray in the printer.
         'middle': The middle input tray in the printer.
         'bottom': The bottom input tray in the printer.
       
       
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         'envelope': The envelope input tray in the printer.
         'manual': The manual feed input tray in the printer.
         'large-capacity': The large capacity input tray in the printer.
         'main': The main input tray
         'side': The side input tray
       
       
       The following standard values are defined for media sizes (from ISO
       DPA):
       
         'iso-a0': Specifies the ISO A0 size: 841 mm by 1189 mm as defined in
            ISO 216
         'iso-a1': Specifies the ISO A1 size: 594 mm by 841 mm as defined in
            ISO 216
         'iso-a2': Specifies the ISO A2 size: 420 mm by 594 mm as defined in
            ISO 216
         'iso-a3': Specifies the ISO A3 size: 297 mm by 420 mm as defined in
            ISO 216
         'iso-a4': Specifies the ISO A4 size: 210 mm by 297 mm as defined in
            ISO 216
         'iso-a5': Specifies the ISO A5 size: 148 mm by 210 mm as defined in
            ISO 216
         'iso-a6': Specifies the ISO A6 size: 105 mm by 148 mm as defined in
            ISO 216
         'iso-a7': Specifies the ISO A7 size: 74 mm by 105 mm as defined in
            ISO 216
         'iso-a8': Specifies the ISO A8 size: 52 mm by 74 mm as defined in ISO
            216
         'iso-a9': Specifies the ISO A9 size: 37 mm by 52 mm as defined in ISO
            216
         'iso-a10': Specifies the ISO A10 size: 26 mm by 37 mm as defined in
            ISO 216
         'iso-b0': Specifies the ISO B0 size: 1000 mm by 1414 mm as defined in
            ISO 216
         'iso-b1': Specifies the ISO B1 size: 707 mm by 1000 mm as defined in
            ISO 216
         'iso-b2': Specifies the ISO B2 size: 500 mm by 707 mm as defined in
            ISO 216
         'iso-b3': Specifies the ISO B3 size: 353 mm by 500 mm as defined in
            ISO 216
         'iso-b4': Specifies the ISO B4 size: 250 mm by 353 mm as defined in
            ISO 216
         'iso-b5': Specifies the ISO B5 size: 176 mm by 250 mm as defined in
            ISO 216
         'iso-b6': Specifies the ISO B6 size: 125 mm by 176 mm as defined in
            ISO 216
         'iso-b7': Specifies the ISO B7 size: 88 mm by 125 mm as defined in
            ISO 216
       
       
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         'iso-b8': Specifies the ISO B8 size: 62 mm by 88 mm as defined in ISO
            216
         'iso-b9': Specifies the ISO B9 size: 44 mm by 62 mm as defined in ISO
            216
         'iso-b10': Specifies the ISO B10 size: 31 mm by 44 mm as defined in
            ISO 216
         'na-letter': Specifies the North American letter size: 8.5 inches by
            11 inches
         'na-legal': Specifies the North American legal size: 8.5 inches by 14
            inches
         'executive': Specifies the executive size (7.25 X 10.5 in)
         'folio': Specifies the folio size (8.5 X 13 in)
         'invoice': Specifies the invoice size (5.5 X 8.5 in)
         'ledger': Specifies the ledger size (11 X 17 in)
         'quarto': Specifies the quarto size (8.5 X 10.83 in)
         'iso-c3': Specifies the ISO C3 size: 324 mm by 458 mm as defined in
            ISO 269
         'iso-c4': Specifies the ISO C4 size: 229 mm by 324 mm as defined in
            ISO 269
         'iso-c5': Specifies the ISO C5 size: 162 mm by 229 mm as defined in
            ISO 269
         'iso-c6': Specifies the ISO C6 size: 114 mm by 162 mm as defined in
            ISO 269
         'iso-designated-long': Specifies the ISO Designated Long size: 110 mm
            by 220 mm as defined in ISO 269
         'na-10x13-envelope': Specifies the North American 10x13 size: 10
            inches by 13 inches
         'na-9x12-envelope': Specifies the North American 9x12 size: 9 inches
            by 12 inches
         'na-number-10-envelope': Specifies the North American number 10
            business envelope size: 4.125 inches by 9.5 inches
         'na-7x9-envelope': Specifies the North American 7x9 inch envelope
            size
         'na-9x11-envelope': Specifies the North American 9x11 inch envelope
            size
         'na-10x14-envelope': Specifies the North American 10x14 inch envelope
            size
         'na-number-9-envelope': Specifies the North American number 9
            business envelope size
         'na-6x9-envelope': Specifies the North American 6x9 envelope size
         'na-10x15-envelope': Specifies the North American 10x15 envelope size
         'monarch-envelope': Specifies the Monarch envelope size (3.87 x 7.5
            in)
         'jis-b0': Specifies the JIS B0 size: 1030mm x 1456mm
         'jis-b1': Specifies the JIS B1 size: 728mm x 1030mm
         'jis-b2': Specifies the JIS B2 size: 515mm x 728mm
         'jis-b3': Specifies the JIS B3 size: 364mm x 515mm
         'jis-b4': Specifies the JIS B4 size: 257mm x 364mm
       
       
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         'jis-b5': Specifies the JIS B5 size: 182mm x 257mm
         'jis-b6': Specifies the JIS B6 size: 128mm x 182mm
         'jis-b7': Specifies the JIS B7 size: 91mm x 128mm
         'jis-b8': Specifies the JIS B8 size: 64mm x 91mm
         'jis-b9': Specifies the JIS B9 size: 45mm x 64mm
         'jis-b10': Specifies the JIS B10 size: 32mm x 45mm
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
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