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Naming Plan for Internet Directory-Enabled Applications
draft-ietf-ids-dirnaming-03

The information below is for an old version of the document that is already published as an RFC.
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This is an older version of an Internet-Draft that was ultimately published as RFC 2377.
Authors Mark Wahl , Dr. Rick Huber , Dr. Srinivas R. Sataluri , Al Grimstad
Last updated 2013-03-02 (Latest revision 1998-01-02)
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draft-ietf-ids-dirnaming-03
IDS Working Group                                            Al Grimstad
INTERNET-DRAFT                                                Rick Huber
                                                                    AT&T
                                                            Sri Sataluri
                                                     Lucent Technologies
                                                             Steve Kille
                                                              Isode Ltd.
                                                               Mark Wahl
                                                     Critical Angle Inc.

                                                       November 26, 1997

        Naming Plan for Internet Directory-Enabled Applications
               Filename: draft-ietf-ids-dirnaming-03.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
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   To learn the current status of any Internet-Draft, please check the
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   ftp.isi.edu (US West Coast).

   Distribution of this document is unlimited.  Editorial comments
   should be sent directly to the authors.  Technical discussion will
   take place on the IETF Integrated Directory Services mailing list,
   ietf-ids@umich.edu.

Abstract

   Application of the conventional X.500 approach to naming has
   heretofore, in the experience of the authors, proven to be an
   obstacle to the wide deployment of directory-enabled applications on
   the Internet.  We propose a new directory naming plan that leverages
   the strengths of the most popular and successful Internet naming
   schemes for naming objects in a hierarchical directory.  This plan
   can, we believe, facilitate the creation of an Internet White Pages

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   Service (IWPS) and other directory-enabled applications by overcoming
   the problems encountered by those using the conventional X.500
   approach to naming.

1.0 Executive Summary

   Application of the conventional X.500 approach to naming has
   heretofore, in the experience of the authors, proven to be an
   obstacle to the wide deployment of directory-enabled applications on
   the Internet.  The required registration infrastructure is either
   non-existent or largely ignored.  The infrastructure that does exist
   is cumbersome to use and tends to produce counterproductive results.
   The attributes used for naming have been confusing for users and
   inflexible to managers and operators of directory servers.

   This paper describes an alternative directory naming plan for the
   construction of an Internet directory infrastructure to support
   directory-enabled applications.

   The plan has the following two main features.  First, it bases the
   root and upper portions of the name hierarchy on the existing
   infrastructure of names from the Domain Name System (DNS). This
   component of the plan makes use of the ideas described in the
   companion paper to this plan, "Using Domains in LDAP Distinguished
   Names" [1].  And second, it provides a number of options for the
   assignment of names to directory leaf objects such as person objects,
   including an option that allows the reuse of existing Internet
   identifiers for people.

   Here, in summary, is our proposal.

   The upper portions of the hierarchical directory tree should be
   constructed using the components of registered DNS names using the
   domain component attribute "dc".  The directory name for the
   organization having the domain name "acme.com" will then be, e.g.,

       dc=acme, dc=com

   Organizations can add additional directory structure, for example to
   support implementation of access control lists or partitioning of
   their directory information, by using registered subdomains of DNS
   names, e.g., the subdomain "corporate.acme.com" can be used as the
   basis for the directory name

       dc=corporate, dc=acme, dc=com

   For naming directory leaf objects such as persons, groups, server
   applications and certification authorities in a hierarchical

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   directory, we propose the use of either the "uid" (user identifier)
   or the "cn" (common name) attribute for the relative distinguished
   name. This plan does not constrain how these two attributes are used.

   One approach to their use, for example, is to employ the uid
   attribute as the RDN when reusing an existing store of identifiers
   and the cn attribute as the RDN when creating new identifiers
   specifically for the directory.  A convenient existing identification
   scheme for person objects is the RFC822 mailbox identifier. So an RDN
   for person employing this store of identifiers would be, e.g.,

       uid=John.Smith@acme.com

   For leaf objects not conveniently identified with such a scheme, the
   "cn" attribute is used, e.g.,

       cn=Reading Room

   Directory distinguished names will thus have the following structure,
   e.g.,

       uid=John.Smith@acme.com, dc=acme, dc=com
       uid=Mary.Jones@acme.com, dc=corporate, dc=acme, dc=com
       uid=J.Smith@worldnet.att.net, dc=legal, dc=acme, dc=com
       cn=Reading Room, dc=physics, dc=national-lab, dc=edu

2.0 The Problem

   The X.500 Directory model [2] can be used to create a world-wide
   distributed directory. The Internet X.500 Directory Pilot has been
   operational for several years and has grown to a size of about 1.5
   million entries of varying quality.  The rate of growth of the pilot
   is far lower than the rate of growth of the Internet during the pilot
   period.

   There are a substantial number of contributing factors that have
   inhibited the growth of this pilot.  The common X.500 approach to
   naming, while not the preponderant problem, has contributed in
   several ways to limit the growth of an Internet White Pages Service
   based on X.500.

   The conventional way to construct names in the X.500 community is
   documented as an informative (i.e., not officially standardized)
   Annex B to X.521. The relative distinguished name (RDN) of a user
   consists of a common name (cn) attribute. This is meant to be what --
   in the user's particular society -- is customarily understood to be
   the name of that user. The distinguished name of a user is the
   combination of the name of some general object, such as an

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   organization or a geographical unit, with the common name. There are
   two main problems with this style of name construction.

   First, the common name attribute, while seeming to be user-friendly,
   cannot be used generally as an RDN in practice.  In any significant
   set of users to be named under the same Directory Information Tree
   (DIT) node there will be collisions on common name.  There is no way
   to overcome this other than either by forcing uniqueness on common
   names, something they do not possess, or by using an additional
   attribute to prevent collisions.  This additional attribute normally
   needs to be unique in a much larger context to have any practical
   value.  The end result is a RDN that is very long and unpopular with
   users.

   Second, and more serious, X.500 has not been able to use any
   significant number of pre-existing names.  Since X.500 naming models
   typically use organization names as part of the hierarchy [2, 3],
   organization names must be registered.  As organization names are
   frequently tied to trademarks and are used in sales and promotions,
   registration can be a difficult and acrimonious process.

   The North American Directory Forum (NADF, now the North Atlantic
   Directory Forum but still the NADF) proposed to avoid the problem of
   registration by using names that were already registered in the
   "civil naming infrastructure" [4][5].  Directory distinguished names
   would be based on an organization's legal name as recognized by some
   governmental agency (county clerk, state secretary of state, etc.) or
   other registering entity such as ANSI.

   This scheme has the significant advantage of keeping directory
   service providers out of disputes about the right to use a particular
   name, but it leads to rather obscure names.  Among these obscurities,
   the legal name almost invariably takes a form that is less familiar
   and longer than what users typically associate with the organization.
   For example, in the US a large proportion of legal organization names
   end with the text ", Inc." as in "Acme, Inc."  Moreover, in the case
   of the US, the civil naming infrastructure does not operate
   nationally, so the organization names it provides must be located
   under state and regional DIT nodes, making them difficult to find
   while browsing the directory.  NADF proposes a way to algorithmically
   derive multi-attribute RDNs which would allow placement of entries or
   aliases in more convenient places in the DIT, but these derived names
   are cumbersome and unpopular.  For example, suppose Nadir is an
   organization that is registered in New Jersey civil naming
   infrastructure under the name "Nadir Networks, Inc."  Its civil
   distinguished name (DN) would then be

       o="Nadir Networks, Inc.", st=New Jersey, c=US

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   while its derived name which is unambiguous under c=US directly is

       o="Nadir Networks, Inc." + st=New Jersey, c=US

   More generally, the requirement for registration of organizations in
   X.500 naming has led to the establishment of national registration
   authorities whose function is mainly limited to assignment of X.500
   organization names.  Because of the very limited attraction of X.500,
   interest in registering an organization with one of these national
   authorities has been minimal.  Finally, multi-national organizations
   are frustrated by a lack of an international registration authority.

3.0 Requirements

   A directory naming plan must provide for names of directory objects
   that are unambiguous (identify only one directory object) within some
   context (namespace), at a minimum within one isolated directory
   server.

   A directory object is simply a set of attribute values. The
   association between a real-world object and a directory object is
   made by directory-enabled applications and is, in the general case,
   one to many.

   The following additional naming characteristics are requirements that
   this naming plan seeks to satisfy:

   a) hierarchical

   The Internet, consisting of a very large number of objects and
   management domains, requires hierarchical names.  Such names permit
   delegation in the name assignment process and partitioning of
   directory information among directory servers.

   b) friendly to loose coupling of directory servers

   One purpose of this naming plan is to define a naming pattern that
   will facilitate one form or another of loose coupling of potentially
   autonomous directory servers into a larger system.

   A name in such a loosely-coupled system should unambiguously identify
   one real-world object.  The real-world object may, however, be
   represented differently (i.e. by different directory objects having
   different attributes) in different (e.g. independently managed)
   servers in the loosely-coupled system.  The plan does not attempt to
   produce names to overcome this likely scenario.  That is, it does not
   attempt to produce a single namespace for all directory objects.
   (This issue is considered in more detail in Section 5.1.)

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   c) readily usable by LDAP clients and servers

   As of this writing, a substantial number of the Lightweight Directory
   Access Protocol (LDAP) [6][7] implementations are currently available
   or soon will be.  The names specified by this naming plan should be
   readily usable by these implementations and applications based on
   them.

   d) friendly to re-use of existing Internet name registries

   As described in Section 2 above, creation of new global name
   registries has been highly problematic.  Therefore, a fundamental
   requirement this plan addresses is to enable the reuse of existing
   Internet name registries such as DNS names and RFC822 mailbox
   identifiers when constructing directory names.

   e) minimally user-friendly

   Although we expect that user interfaces of directory-enabled
   applications will avoid exposing users to DNs, it is unlikely that
   users can be totally insulated from them.  For this reason, the
   naming plan should permit use of familiar information in name
   construction.  Minimally, a user should be capable of recognizing the
   information encoded in his/her own DN.  Names that are totally opaque
   to users cannot meet this requirement.

4.0 Name Construction

   The paper assumes familiarity with the terminology and concepts
   behind the terms distinguished name (DN) and relative distinguished
   name (RDN) [2][8][9].

   We describe how DNs can be constructed using three attribute types,
   domainComponent (dc), userID (uid) and commonName (cn).  They are
   each described in turn.

4.1 Domain Component (dc)

   The domain component attribute is defined and registered in RFC1274
   [3][10].  It is used in the construction of a DN from a domain name.
   Details of the construction algorithm is described in "Using Domains
   in LDAP Distinguished Names" [1].

   An organization wishing to deploy a directory following this naming
   plan would proceed as follows.  Consider an organization, for example
   "Acme, Inc.", having the registered domain name "acme.com".  It would
   construct the DN

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       dc=acme, dc=com

   from its domain name.  It would then use this DN as the root of its
   subtree of directory information.

   The DN itself can be used to identify a directory organization object
   that represents information about the organization. The directory
   schema required to enable this is described below in section 5.2.

   The subordinates of the DN will be directory objects related to the
   organization.  The domain component attribute can be used to name
   subdivisions of the organization such as organizational units and
   localities.  Acme, for example, might use the domain names
   "corporate.acme.com" and "engineering.acme.com" to construct the
   names

       dc=corporate, dc=acme, dc=com
       dc=engineering, dc=acme, dc=com

   under which to place its directory objects.  The directory schema
   required to name organizationalUnit and locality objects in this way
   is described below in section 5.2.

   Use of this attribute for the RDN of directory objects of class
   "domain" is also possible [1].

4.2 User ID (uid)

   The userid (uid) attribute is defined and registered in RFC1274
   [3][10].

   This attribute may be used to construct the RDN for directory objects
   subordinate to objects named according to the procedure described in
   Section 4.1.  This plan does not constrain how this attribute is
   used.

4.3 Common Name (cn)

   The commonName (cn) attribute is defined and registered in X.500
   [3][11].

   This attribute may be used to construct the RDN for directory objects
   subordinate to objects named according to the procedure described in
   Section 4.1.  This plan does not constrain how this attribute is
   used.

4.4 Examples of uid and cn Usage

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   Although this plan places no constraints on the use of the uid and cn
   attributes for name construction, we would like to offer some
   suggestions by way of examples.

   In practice, we have used uid for the RDN for person objects were we
   could make use of an existing registry of names and cn for other
   objects.

   Examples of existing registries of identifiers for person objects are
   RFC822 mailbox identifiers, employee numbers and employee "handles".
   Aside from the convenience to administrators of re-use of an existing
   store of identifiers, if it is ever necessary to display to a user
   his/her DN, there is some hope that it will be recognizable when such
   identifiers are used.

   We have found RFC822 mailbox identifiers a particularly convenient
   source for name construction.  When a person has several e-mail
   addresses, one will be selected for the purpose of user
   identification.  We call this the "distinguished" e-mail address or
   the "distinguished" RFC822 mailbox identifier for the user.

   For example, if there is a user affiliated with the organization Acme
   having distinguished e-mail address J.Smith@acme.com, the uid
   attribute will be:

       uid=J.Smith@acme.com

   The domain component attributes of a user's DN will normally be
   constructed from the domain name of his/her distinguished e-mail
   address.  That is, for the user uid=J.Smith@acme.com the domain
   component attributes would typically be:

       dc=acme, dc=com

   The full LDAP DN for this user would then be:

       uid=J.Smith@acme.com, dc=acme, dc=com

   Directory administrators having several RFC822 identifiers to choose
   from when constructing a DN for a user should consider the following
   factors:

       o Machine-independent addresses are likely to be more stable,
         resulting in directory names that change less. Thus an
         identifier such as:

             js@acme.com

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         may well be preferable to one such as:

            js@blaster.third-floor.acme.com.

       o Use of some form of "handle" for the "local" part that is
         distinct from a user's real name may result in fewer collisions
         and thereby lessen user pain and suffering.  Thus the
         identifier:

             js@acme.com

         may well be preferable to one such as:

             J.Smith@acme.com

   Practical experience with use of the RFC822 mailbox identifier scheme
   described here has shown that there are situations where it is
   convenient to use such identifies for all users in a particular
   population, although a few users do not, in fact, possess working
   mailboxes.  For example, an organization may have a existing unique
   identification scheme for all employees that is used as a alias to
   the employees' real mailboxes -- which may be quite heterogeneous in
   structure.  The identification scheme works for all employees to
   identify unambiguously each employee; it only works as an e-mail
   alias for those employees having real mailboxes.  For this reason it
   would be a bad assumption for directory-enabled applications to
   assume the uid to be a valid mailbox; the value(s) of the mail
   attribute should always be checked.

   It is important to emphasize that the elements of the domain name of
   an RFC822 identifier may, BUT NEED NOT, be the same as the domain
   components of the DN.  This means that the domain components provide
   a degree of freedom to support access control or other directory
   structuring requirements that need not be mechanically reflected in
   the user's e-mail address.  We do not want under any condition to
   force the user's e-mail address to change just to facilitate a new
   system requirement such as a modification in an access control
   structure.  It should also be noted that while we do not require that
   the domain components match the RFC822 identifier, we DO require that
   the concatenated domain components form a registered domain name,
   that is, one that is represented in the DNS. This automatically
   avoids name conflicts in the directory hierarchy.

   To provide an example of a DN which deviates from what might be
   considered the default structure, consider the following scenario.

   Suppose that J.Smith needs to be granted special permissions to
   information in the dc=acme, dc=com part of the LDAP DIT.  Since it

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   will be, in general, easier to organize special users by their name
   structure than via groups (an arbitrary collection of DNs), we use
   subdomains for this purpose.  Suppose the special permissions were
   required by users in the MIS organizational unit.  A subdomain
   "mis.acme.com" is established, if it does not already exist,
   according to normal DNS procedures.  The special permissions will be
   granted to users with the name structure:

       uid=*, dc=mis, dc=acme, dc=com

   The DN of J.Smith in this case will be:

       uid=J.Smith@acme.com, dc=mis, dc=acme, dc=com

   In principal, there is nothing to prevent the domain name elements of
   the RFC822 identifier from being completely different from the domain
   components of the DN.  For instance, the DN for a J.Smith could be:

       uid=J.Smith@worldnet.att.net, dc=mis, dc=acme, dc=com

   While we do not REQUIRE that the domain name part of the uid match
   the dc components of the directory distinguished name, we suggest
   that this be done where possible. At a minimum, if the most
   significant pieces of the DN and the uid are the same (i.e.,
   "dc=acme, dc=com" and "acme.com") the likelihood, based on a
   knowledge of a user's e-mail address, of discovering an appropriate
   directory system to contact to find information about the user is
   greatly enhanced.

   The example above represents a situation where this suggestion isn't
   possible because some of the users in a population have mailbox
   identifiers that differ from the pattern of the rest of the users,
   e.g., most mailboxes are of the form local@acme.com, but a
   subpopulation have mailboxes from an ISP and therefore mailboxes of
   the form local@worldnet.att.net.

5.0 Implementation Issues

5.1 Directory Services Considerations

   We envision the deployment of LDAP-based directory services on the
   Internet to take the form of loosely coupled LDAP servers. This
   coupling will occur at two levels.

   Firstly, LDAP servers will be loosely connected into islands (i.e. a
   set of servers sharing a single DN namespace). The glue connecting
   the islands will be LDAP referral [12] information configured into
   the LDAP servers. An LDAP search directed to any server in such an

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   island can be answered, if the information is not available to that
   server, by an LDAP referral to another, more appropriate server
   within the same island.

   Secondly, various techniques will be used span LDAP islands. The
   concept that enables such techniques is the LDAP URL [13]. By
   combining a DNS host name and port (corresponding to one or more LDAP
   servers) with a DN, the LDAP URL provides unified high-level
   identification scheme (an LDAP URL namespace) for directory objects.

   Because an LDAP referral is expressed as one or more LDAP URL, these
   two levels of coupling may not sharply distinguished in practice.

   We do not envision the X.500 model of a single DIT (i.e. a single DN
   namespace) to be viable in an environment of competing service
   providers.  This naming plan does not attempt to produce DNs to hide
   the possibility that a given real-world object may have independently
   managed directory objects (entries) associated with it.

5.2 Directory Schema Implications of the Naming Plan

   The traditional directory schema(s) developed for the X.500 standard
   and its application to the Internet [4] require extension to be used
   with the naming plan developed here. The extensions described below
   attempt to reuse existing schema elements as much as possible. The
   directory objects for which extensions are required are:
   organization, organizational unit, and various classes of leaf
   objects. We describe the schema modifications below for organization,
   organizationalUnit and selected leaf classes.

   So as to continue to use existing structural object classes to the
   extent possible, we propose supplementing entries based on these
   classes with additional information from two new auxiliary object
   classes, dcObject and uidObject. They are specified using the
   notation in Section 4 of [14].

   The auxiliary object class dcObject is defined in "Using Domains in
   LDAP Distinguished Names" [1].

   The auxiliary object class uidObject is defined as:

   ( OID-TBD NAME 'uidObject' SUP top AUXILIARY MUST uid )

   In a pure X.500 context, our schema would also require the definition
   of new name forms and structure rules. These concepts are not
   required, however, for the specification of LDAP schemas.

5.2.1 Organization Schema

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   The dc attribute is employed to construct the RDN of an organization
   object.  This is enabled by adding the auxiliary class dcObject to
   the organization's objectClass attribute.

5.2.2 Organizational Unit Schema

   The dc attribute is employed to construct the RDN of an
   organizationalUnit object (which is subordinate in the DIT to either
   an organization or an organizationalUnit object).  This is enabled by
   adding the auxiliary class dcObject to the organizational unit's
   objectClass attribute.

5.2.3 Person Schema

   No schema extensions are required for person objects if either the
   inetOrgPerson [15] (preferred) or the newPilotPerson object classes
   are used. The attribute uid is permissible in each class. For
   consistency, the uidObject could be added to person entry objectClass
   attributes to assist applications filtering on this object class
   attribute value. Use of other classes for person objects with RDN
   constructed with the uid attribute such as organizationalPerson
   requires the use of the uidObject class.

   It has been traditional in X.500 and LDAP directory services to
   employ the common name (cn) attribute in naming.  While this naming
   plan doesn't require use of the cn attribute in naming, it should be
   stressed that it is a required attribute in any class derived from
   the person class and is still quite important.  It will play a
   significant role in enabling searches to find user entries of
   interest.

5.2.4 Certification Authority Schema

   The certification authority (CA) object class is an auxiliary class,
   meaning it is essentially a set of additional attributes for a base
   class such as organizationalRole, organization, organizationalUnit or
   person.  Except in the case where the base structural class is
   inetOrgPerson, use of the uid attribute to construct the RDN of a CA
   will require the auxiliary class uidObject to permit the uid
   attribute to be used. In the cases where organizationalUnit or
   organization is the base class for a CA, use of the auxiliary class
   dcObject will permit the RDN of the CA to be a domain component.

5.2.5 Server and Server Application Schema

   Servers and server applications are typically represented, for want
   of anything better, by entries of the object class applicationProcess

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   (or a class derived from it).  Sometimes the class applicationEntity
   is used.  In either case, the uid attribute should probably not be
   employed to construct the RDN of a server or server application
   object.  The standard schema uses the attribute cn for such RDNs.

   Suppose one wants to use this naming plan both in the construction of
   DNs for SSL server certificates and for their storage in a directory.
   It is customary for clients connecting via SSL to compare the
   server's domain name (e.g. from the URL used to contact the server)
   with the value of the cn attribute in the subject field (i.e.
   subject's DN) of the server's certificate. For this reason, it is
   common practice to set the cn attribute to the server's domain name.

   The naming and schema to handle this situation is best explained by
   an example. Consider the server "host.acme.com". Following the
   algorithm in "Using Domains in LDAP Distinguished Names" [1], the DN
   dc=host, dc=acme, dc=com is constructed. To conform to the existing
   practices just described, the server's subject DN for the SSL server
   certificate should be cn=host.acme.com, dc=host, dc=acme, dc=com and
   the server's certificate should be stored in a directory entry with
   this name. This entry should use application process or application
   entity as its structural object class and strong authentication user
   as is auxiliary class.

6.0 Security Considerations

   Although access controls may be placed on portions of the DIT to deny
   browse access to unauthorized clients, it may be possible to infer
   directory names and DIT structure in such sensitive portions of the
   DIT from the results of DNS queries. Providing public visibility to
   some portions of the DIT may assist those make such inferences.

7.0 Acknowledgments

   This plan has emerged in the course of a number of fruitful
   discussions, especially with David Chadwick, John Dale, Joe Gajewski,
   Mark Jackson, Ryan Moats, Tom Spencer and Chris Tzu.

8.0 References

   [1]     S. Kille, M. Wahl, A. Grimstad, R. Huber, S. Sataluri,
           "Using Domains in LDAP Distinguished Names", Internet
           Draft <draft-ietf-asid-ldap-domains-02.txt>, August
           1997.

   [2]     X.500: The Directory -- Overview of Concepts, Models, and
           Service, CCITT Recommendation X.500, December, 1988.

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   [3]     P. Barker, and S. Kille, "The COSINE and Internet X.500
           Schema", RFC1274, 11/27/1991.

   [4]     The North American Directory Forum, "A Naming Scheme for
           c=US", RFC1255, September 1991.

   [5]     The North American Directory Forum, "NADF Standing Documents:
           A Brief Overview", RFC 1417, The North American Directory
           Forum", NADF, February 1993.

   [6]     W. Yeong, T. Howes, and S. Kille, "Lightweight Directory
           Access Protocol", RFC1777, 03/28/1995.

   [7]     M. Wahl, T. Howes, and S. Kille, "Lightweight Directory
           Access Protocol (v3)", Internet Draft <draft-ietf-asid-
           ldapv3-protocol-04.txt>, March 1997.

   [8]     S. Kille, "A String Representation of Distinguished Names",
           RFC1779, 03/28/1995.

   [9]     M. Wahl, S. Kille, T. Howes, "Lightweight Directory Access
           Protocol (v3): UTF-8 String Representation of Distinguished
           Names", Internet Draft <draft-ietf-asid-ldapv3-dn-03.txt>,
           April, 1997.

   [10]    M. Wahl, "A Summary of the Pilot X.500 Schema for use in
           LDAPv3", Internet Draft <draft-ietf-asid-schema-pilot-
           00.txt>, March 1997.

   [11]    M. Wahl, "A Summary of the X.500 User Schema for use with
           LDAPv3", Internet Draft <draft-ietf-asid-ldapv3schema-x500
           01.txt>, July 1997.

   [12]    T. Howes, M. Wahl, "Referrals and Knowledge References in
           LDAP Directories", Internet Draft, <draft-ietf-asid-ldapv3-
           referral-00.txt>, May 1997.

   [13]    T. Howes, M. Smith, "The LDAP URL Format", Internet Draft,
           <draft-ietf-asid-ldapv3-url-04.txt>, August 1997.

   [14]    M. Wahl, A. Coulbeck, T. Howes, S. Kille,  "Lightweight
           Directory Access Protocol (v3): Attribute Syntax
           Definitions", Internet Draft <draft-ietf-asid-ldapv3-
           attributes-07.txt>, August 1997.

   [15]    M. Smith, "Definition of the inetOrgPerson Object Class",
           Internet Draft <draft-ietf-asid-inetorgperson-01.txt>,
           July 1997.

Grimstad, et al.                                               [Page 14]


INTERNET-DRAFT                Naming Plan                  November 1997

12.  Authors' Addresses

       Al Grimstad
       AT&T
       Room 1C-429, 101 Crawfords Corner Road
       Holmdel, NJ 07733-3030
       USA

       EMail:  alg@att.com

       Rick Huber
       AT&T
       Room 1B-433, 101 Crawfords Corner Road
       Holmdel, NJ 07733-3030
       USA

       EMail:  rvh@att.com

       Sri Sataluri
       Lucent Technologies
       Room 4D-335, 101 Crawfords Corner Road
       Holmdel, NJ 07733-3030
       USA

       EMail:  srs@lucent.com

       Steve Kille
       Isode Limited
       The Dome, The Square
       Richmond
       TW9 1DT
       UK

       Phone:  +44-181-332-9091
       EMail:  S.Kille@isode.com

       Mark Wahl
       Critical Angle Inc.
       4815 W Braker Lane #502-385
       Austin, TX 78759
       USA

       EMail:  M.Wahl@critical-angle.com

Grimstad, et al.                                               [Page 15]