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DUA Metrics (OSI-DS 33 (v2))
draft-ietf-osids-dua-metrics-00

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 1431.
Author Paul Barker
Last updated 2013-03-02 (Latest revision 1992-09-23)
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draft-ietf-osids-dua-metrics-00
Network Working                                            Paul Barker
Group                                        University College London
INTERNET-DRAFT                                          September 1992

                             DUA Metrics

                           (OSI-DS 33 (v2))

Status of this Memo
This document defines a set of criteria by which a DUA implementation,
or more precisely a Directory user interface, may be judged.
Particular issues covered include terminal requirements; style of
interface; target user; default object classes and attribute types;
use of DAP; error handling.  The focus of the note is on ``white
pages'' DUAs:  this is a reflection of the current information base.
Nevertheless much of the document will be applicable to DUAs developed
for other types of Directory usage.
Please send comments to the authors or to the discussion group
<osi-ds@CS.UCL.AC.UK>.

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.
Internet Drafts may be updated, replaced, or obsoleted by other
documents at any time.  It is not appropriate to use Internet Drafts
as reference material or to cite them other than as a "working draft"
or "work in progress."
Please check the I-D abstract listing contained in each Internet Draft
directory to learn the current status of this or any other Internet
Draft.



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Contents

1   Overview                                                         3

2   General Information                                              4

3   Conformance to OSI Standards                                     6
    3.1    Directory protocols................................       6
    3.2    Protocol stacks....................................       6

    3.3    Schema ............................................       7
    3.4    DIT structure  ....................................       7

4   Conformance to Research Community Standards                      7

5   The General Style of the DUA                                     8

6   Schema                                                           9

    6.1    Object Classes and Attribute Types ................       9
    6.2    DIT structure  ....................................      10

7   Entering queries                                                10

8   Strategy for locating entries                                   11

9   Displaying results                                              12

10  Association Handling                                            13

11  Suitability for management                                      14

12  Query Resolution                                                15

13  International Languages                                         19

14  User Friendliness                                               19

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15  Operational Use                                                 20

1  Overview

The purpose of this document is to define some metrics by which DUA
products can be measured.  It should be first be noted that the use of
the term ``DUA'' is rather misleading.  There is an assumption here
that the DUA is implemented correctly and is able to ``talk'' valid
X.500 protocol:  this is a sine qua non.  Instead, this document seeks
to draw out the characteristics of Directory user interfaces.
However, the term DUA is persisted with as it is used by most people
when referring to Directory user interfaces.
The format of these DUA metrics is essentially a questionnaire which
extracts a detailed description of a user interface.  DUAs come in
very different forms.  Many make use of windowing environments,
offering a ``high-tech'' view of the Directory, while others are
designed to work in a terminal environment.  Some interfaces offer
extensive control over the Directory, and thus may be well-suited to
Directory managers, while others are aimed more at the novice user.
Some interfaces are configurable to allow searches for any attribute
in any part of the DIT, while others lack this generality but are
focussed on handling the most typical queries well.

In many aspects, it is almost impossible to say that one DUA is better
than other from looking at the responses to question in this document.
A flexible management tool will be better for management than a DUA
aimed at servicing simple look-ups, and vice-versa.  Furthermore, in
other areas, there are several radically different approaches to a
problem, but it is not as yet clear whether one approach is better
than another.  One example of this is the extent to which a DUA
provides an abstraction of the underlying DIT hierarchy, either
emphasising the world as a tree or trying to conceal this from the
user.
However, in other aspects, such as whether the DUA can actually find
the entries required, and if so, how quickly, can be directly measured
in some way.
Throughout this document, some of the questions posed are annotated
with a square-bracketed points score and an explanation as to how the
points should be allocated.  For example, a question might be appended
with ``[2 if yes]'', indicating score 2 points for an affirmative
answer to that question.  These points scores should be collated in
Table 1 at the end of the document, and this table constitutes a

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measure of the DUA. The metrics are on a section by section basis,
which should help the reader who is seeking, for example, a DUA with
good management capabilities which runs on a wide variety of
platforms, to focus on the critical aspects of a DUA for the
particular requirement.

2  General Information

This section contains general information about the implementation
under discussion.

1.  Name of the implementation ......................................

2.  Version number of the DUA described in this document ............

3.  Are further versions planned?  [3 if yes] .......................

4.  Name and address of supplier or person to contact ...............
 ....................................................................
 ....................................................................
 ....................................................................
 ....................................................................
 ....................................................................
 ....................................................................

5.  Describe the hardware and software platforms on which the DUA will
    run.  Some DUAs are split into a user interface part, and a DUA
    server part, communicating by means of a protocol.  If the DUA is
    of the type where the DUA protocol machinery and user agent are
    implemented in a single process, complete only the user interface
    section, and indicate ``n/a'' for the DUA server and
    communications protocol questions.

   (a)  User interface part [1 per platform, up to a maximum of 4]

        i.  Hardware (If appropriate, can summarise as, for example,

       ii.  O/S (state version if critical)

            A.  UNIX (be sure to indicate which flavour - e.g.  SYSV,
                BSD, SUNOS, etc) ....................................
             ........................................................

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            B.  VMS) ................................................

            C.  MS-DOS ..............................................

            D.  MS-Windows ..........................................

            E.  Macintosh ...........................................

            F.  Other) ..............................................

   (b)  DUA server part (or n/a) ....................................

        i.  Hardware (If appropriate, can summarise as, for example,
            ``generic UNIX platform'', or ``386 PC'') ...............

       ii.  O/S (state version if critical)

            A.  UNIX (be sure to indicate which flavour - e.g.  SYSV,
                BSD, SUNOS, etc) ....................................

            B.  VMS) ................................................

            C.  MS-DOS ..............................................

            D.  Macintosh ...........................................

            E.  Other) ..............................................

      iii.  How does the user interface communicate with the DUA
            server?

            A.  Directory Assistance Service, as described in RFC1202
             ........................................................

            B.  DIXIE protocol, as described in RFC1249 .............

            C.  LDAP protocol, as described in Internet Draft OSI-DS
                26

            D.  Other ...............................................

   (c)  Name any other software required to run the DUA which is not
        supplied with the operating system or with the DUA software
        itself.  Examples might include X.500 DAP libraries, or

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        communications software .....................................

6.  Is the software free?  If the DUA needs other packages, are these
    also freely available?  [3 if completely free] ..................
 ....................................................................

3  Conformance to OSI Standards

3.1  Directory protocols

7.  Please list all conformance testing work applied to the DUA
    implementation (here the term DUA is used correctly in the sense
    of the DUA protocol machinery) [2 if any conformance work has been
    done] ...........................................................
 ....................................................................

3.2  Protocol stacks

For the next two questions, [2 per stack supported for up to 4 stacks]

8.  Which of the following transport and network layer protocols does
    the DUA support:

   (a)  TP.x over CONS (state transport class) ......................

   (b)  TP.4 over CLNS ..............................................

9.  Does the DUA support other transport and ``network'' layer
    protocols?

   (a)  TP.x over RFC1006 over TCP/IP (state transport class) .......

   (b)  TP.x over X.25(1980) (state transport class) ................

   (c)  State any other options supported.  .........................

10. Does the DUA also run over any lightweight stack?  If so, describe
    it with reference to the OSI seven layer model [3] ..............
 ....................................................................

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3.3  Schema

11. Does the DUA support the full schema in X.520 and X.521 (y/n)?
    (Omissions should be described in response to a later question) [2
    for full schema support] ........................................

3.4  DIT structure

12. Does the DUA only follow object class hierarchies which conform to
    the suggested DIT structure in X.521?............................

4  Conformance to Research Community Standards

The COSINE and Internet Directory Pilots have agreed a set of
extensions to the standard, which make for a more cohesive pilot.
This section is about conformance to these extensions.

13. Does the DUA fully support RFC1274, ``The COSINE and Internet
    X.500 Schema'' (y/n)?  (Omissions should be described in response
    to a later question) [2 for full support] .......................

14. Can the DUA handle referrals whose network addresses conform to
    RFC1277, ``Encoding Network Addresses to support operation over
    non-OSI lower layers''?  [2 if yes] .............................

15. Does the DUA handle the Distinguished Name string syntax described
    in OSI-DS 23, ``A String Representation of Distinguished Names''
    [2 if yes] ......................................................
 ....................................................................

16. Does the DUA use the user-friendly naming query resolution
    described in OSI-DS 24, ``Using the OSI Directory to achieve User
    Friendly Naming'' [2 if yes] ....................................

17. Does the DUA make use of the Quality of Service schema extensions
    described in OSI-DS 15, ``Handling QOS (Quality of service) in the
    Directory'' [2 if yes] ..........................................

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5  The General Style of the DUA

18. Is this a ``white pages'' interface, designed to give access to
    information about people within organisations?  If not, state the
    types of information at which this interface is targetted .......
 ....................................................................

19. If this is a white pages DUA, who is it principally designed to
    serve?  Indicate more than one of the following categories if
    appropriate (but please do not fill in so may categories as to
    hide due emphasis):  [mark allocated should be the highest for any
    single classification]

   (a)  The ordinary user, who has no understanding of X.500, the
        hierarchical DIT, the state of advancement of the pilot, etc.
        [10] ........................................................

   (b)  A secretary who wants to do telephone or room number look-ups
        within their department or organisation [8] .................

   (c)  A computer-literate user, who habitually uses a wide-range of
        network services [6] ........................................

   (d)  An organisation's (or department's) data manager [4] ........

   (e)  A Directory system manager [2] ..............................

20. Which best describes the use the DUA makes of the user's terminal?

   (a)  Scrolling, line-mode interface ..............................

   (b)  Full screen, ``vt100'' style interface ......................

   (c)  X-Windows ...................................................

   (d)  MS-Windows ..................................................

   (e)  Macintosh ...................................................

   (f)  Other .......................................................

21. Does the DUA tend to emphasise or de-emphasise the DIT hierarchy?

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 ....................................................................

22. Describe the interface in your own terms (up to about 50 words)
 ....................................................................
 ....................................................................
 ....................................................................
 ....................................................................
 ....................................................................
 ....................................................................
 ....................................................................

6  Schema

6.1  Object Classes and Attribute Types

Some DUAs are tightly focussed on answering particular queries:  for
example, white pages look-ups for information about people.  Others
offer more general capabilities.  Please answer this question
accordingly.

23. If the DUA has a tight focus, state:

   (a)  The target object classes ...................................
     ................................................................

   (b)  The default attribute types .................................
     ................................................................

   (c)  Other attribute types which may be configured.  This might be
        answered as, for example, ``all barring photo and audio'', or
        as a list of supported attribute types ......................
     ................................................................

24. If the DUA has more general capabilities, state:

   (a)  State any object classes in X.521 which cannot be searched for
     ................................................................

   (b)  State any object classes in RFC1274 which cannot be searched
        for..........................................................
     ................................................................

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   (c)  State any attributes in X.521 which cannot be displayed......
     ................................................................

   (d)  State any attributes in RFC1274 which cannot be displayed....
     ................................................................

6.2  DIT structure

25. DUAs often have a default object class hierarchy (e.g.  it might
    assume countries at the root of the DIT, organisations immediately
    under countries, and people somewhere under organisations.
    Describe the type of hierarchy which the DUA most closely accords
    to:

   (a)  Rigid .......................................................

   (b)  Rigid, but several hierarchies supported ....................

   (c)  Default hierarchy offered, but many hierarchies are supported
     ................................................................

   (d)  Default hierarchy offered, but DUA fully flexible ...........

   (e)  No default hierarchy, DUA fully flexible ....................

26. If a default hierarchy is offered, please describe it ...........
 ....................................................................
 ....................................................................
 ....................................................................

27. State any hierarchies, which are valid according to X.521's
    suggested DIT structure, but which cannot be queried (exclude
    hierarchies which cannot be queried because the DUA does not query
    for entries of particular object classes) .......................
 ....................................................................

7  Entering queries

The term ``querying'' is used here as a generic term for finding an
entry, whether it be as a simple look-up, or the prelude to a
modification operation.

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28. Which best describes the query entry style?

   (a)  Form filling (user responds to a set of prompts) ............

        i.  Query specified first, then resolved ....................

       ii.  Query entry and resolution mixed ........................

      iii.  Both modes possible .....................................

   (b)  Queries entered as ``user-friendly names'' ..................

   (c)  Querying is by ``navigating'' around the DIT, the user
        searching and selecting .....................................

   (d)  Other (please describe) .....................................
     ................................................................

8  Strategy for locating entries

A number of strategies are employed by DUAs to find the entry the user
is looking for.  These have implications for user-friendliness and
performance.  For example, an interface which makes extensive use of
search operations may be excellent at finding entries, but at the cost
of being intolerably slow.

29. Which of the following strategies most closely accords with the
    behaviour of the DUA?

   (a)  The DUA always uses search operations to find entries .......

   (b)  The DUA offers users a list of entries, and invites the user
        to select from the list .....................................

   (c)  The DUA only tries read operations (i.e.  the DN must be
        exactly right) ..............................................

   (d)  The DUA tries read operations first, then searches for
        something similar if no entry can be found ..................

   (e)  The DUA tries read operations first, then offers a list of
        possible entries if no entry can be found ...................

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   (f)  User explicitly controls the X.500 operation which is invoked

   (g)  Other.  Please describe......................................
     ................................................................

30. Does the DUA allow a user to ``list'' (either by the list
    operation or by a single level search operation) all the child
    entries of a node (notwithstanding administrative limits)?  .....

31. Does the DUA follow aliases?  ...................................
    If so, does it do so:

   (a)  Always?  ....................................................

   (b)  Optionally?  ................................................

32. Will the DUA optionally follow links to other entries by using
    attributes such as seeAlso and roleOccupant with a DN syntax?  ..

9  Displaying results

33. Are the strings used to describe attribute types freely and
    independently configurable?  [2] ................................

34. Name any attribute types where the attribute values may be
    presented in local formats?  (For example, it may be possible to
    configure the display of telephone numbers so that local numbers
    are shown as extensions, rather than with the full international
    dialling code.)  [1 per attribute, up to a maximum of 4] ........
 ....................................................................

35. Does the DUA allow for the display of more than one result at a
    time (showing attribute values other than the name of the entry)?
    If so, how many entries may be displayed in response to a single
    query?  [2 if feature provided] .................................
 ....................................................................

36. Does the DUA support the notion of a quick synopsis, where a small
    core of attributes is retrieved initially, and a larger set is
    returned if required?  [2 if yes] ...............................

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37. What does the DUA do with attribute types it doesn't support in
    its sub-schema, but which have a standard syntax?  ..............

38. What does the DUA do with attributes which have are not in its
    sub-schema, and which have a non-standard syntax?

   (a)  Ignore them?  ...............................................

   (b)  Tell user, but don't display?  ..............................

   (c)  Display hex BER encoded value?  .............................

   (d)  Display in some other format?  ..............................

10  Association Handling

This section is concerned with how a DUA handles its association with
the Directory.

39. How/where is the access point to the Directory configured?  If
    more than one method, indicate which ways are possible.  [1 per
    method, up to maximum of 3]

   (a)  In a system-wide tailor file ................................

   (b)  In a per user tailor file ...................................

   (c)  As a run-time command line argument .........................

   (d)  Other.  Please describe .....................................
     ................................................................

40. Does the DUA allow for automatic connection to a back-up DSA if
    the access point DSA is unavailable?  [2 if yes] ................

41. Can the DUA keep connections open to more than one DSA at a time?
    [1 if yes] ......................................................
 ....................................................................

42. Does the DUA keep an idle connection open to the DSA(s).  If not,
    describe the timeout strategy.  [1 if yes] ......................
 ....................................................................

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43. Does the DUA handle referrals automatically?  [2 if yes] ........
    If not:  does the DUA handle referrals at all?  [1 if yes] ......

44. Does the DUA make use of asynchronous operations?

   (a)  Does the DUA bind asynchronously?  [2 if yes]................

   (b)  Are the operations handled asynchronously?  .................
        If so, is this true for:

        i.  All operations?  [2 if yes] .............................

       ii.  Some operations?  [1 if yes] ............................

45. Does the DUA use size and time limits by default?  [2 if no
    limits, or limits may be over-ridden] If so:  ...................

   (a)  What size limit is used?  ...................................

   (b)  What time limit is used?  ...................................

   (c)  Are these limits overridable?  ..............................

11  Suitability for management

This section is intended to establish the range of operations
supported by the DUA and, in particular, whether it is suitable for
management tasks.

46. Is it possible to invoke all the operations in the Directory
    Abstract Service?  If not, say which operations it does use [2 if
    all] ............................................................
 ....................................................................

47. Is the user given full control over the service controls?  If not,
    say which may be controlled, or none at all [2 if full, 1 if some
    control] ........................................................
 ....................................................................

48. Is it possible to manage system attributes with the DUA? If so,
    indicate which DSA implementations for which this DUA provides
    management capabilities.  .......................................

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   (a)  Knowledge [1]................................................

   (b)  Replication information [1] .................................

   (c)  Other .......................................................

49. Access control notwithstanding, does the DUA allow the following?

   (a)  Attribute management [2 for all below, 1 for some]

        i.  Addition ................................................

       ii.  Modification ............................................

      iii.  Deletion ................................................

   (b)  Entry management [2 for all below, 1 for some]

        i.  Addition ................................................

       ii.  Modification ............................................

      iii.  Deletion ................................................

       iv.  Renaming ................................................

12  Query Resolution

This section discusses the process of query resolution.  While two
DUAs may both be able to resolve a query using the same information,
one may do so much more quickly than the other.  Some DUAs may be more
``economic'' in their use of DAP operations to achieve the same
results.  Some DUAs may find the correct results even when the users'
input corresponds rather weakly to Directory names.
Three aspects of query resolution are measured:

 o  Does the DUA actually find the required entry?

 o  If the required entry is found, how many entries were returned as
    well?

 o  How ``expensive'' was the query in terms of underlying X.500

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    operations, whether the query was resolved successfully or not?

The following set of queries might all conceivably be resolved such
that the author's Directory entry be found.  The queries are split
into 2 groups:  the first group SHOULD pose no difficulties for a
reasonable DUA; the second group are more problematic.
In each case, award [2] marks if the query found the author's entry
successfully.  The expensiveness of each query should be measured
using the following formula, which introduces the notion of
SearchStones!  The SearchStone rating is calculated by adding together
the total operations used in attempting to resolve a query, weighted
thus:

 o  Bind [5]

 o  Read operation [1]

 o  List operation [2]

 o  Search single level for countries, organisations or localities [3]

 o  Search single level for organisational units, people or roles 1[3]

 o  Search subtree [5]

The notion of SearchStones merits some further explanation and the
statement of some caveats.

The idea is to give some broad brush view of the work being undertaken
by a DUA to retrieve an entry.  There will be some correspondence
between a low SearchStone rating and a DUA responding quickly, and
vice-versa, although this correlation is not consistent, for reasons
given below.  It would be desirable to be able to have some timing
information for the resolution of queries, but such results would only
be meaningful if the tests were for target entries widely distributed
----------------------------
    1. The single level searches have been separated into two
categories in acknowledgement that certain types of search are much
more likely to span multiple DSAs than others.  The weightings are the
same for the moment because of the pervasiveness of the Quipu
implementation, which replicates all sibling entries in a single DSA,
whatever the level in the DIT

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throughout the DIT. Maybe this is something for the future?
In the meantime it is worth noting some of the factors which militate
against simple minded interpretation of the SearchStones.

 o  The DIT is not uniform, with the depth varying considerably

 o  While the DIT is currently mastered mostly by DSAs of a single
    implementation, this will be decreasingly the case, and other DSAs
    may have very different performance profiles.

 o  Different directory domains are already adopting different
    strategies on information replication with profound performance
    implications.

 o  No weighting is given to different search filters, or to boolean
    combinations of filters.

While acknowledging the difficulty of the exercise, there are counter
arguments:

 o  Some DUAs are better than others at finding the required results

 o  Some DUAs will get the required results more quickly than most

 o  DUA designers have to build DUAs in the knowledge that the DIT is
    heterogeneous with respect to DSA implementation and DIT structure

One possible way forward would be to refine the test queries such that
they better represented the diversity of the DIT. However, as a first
step, the tests are restricted to queries which could reasonably be
constructed as searches for the author's entry.  The author's entry is
held in part of the DIT which is representative of much of the current
DIT.
It is suggested that in order to normalise the tests as much as
possible, that testing be performed by connecting to the target DSA
directly.  The DSA's name is ``cn=Vicuna, c=GB'', and the addresses of
the DSA may be found in the presentation address attribute for that
entry.
Note that the SearchStone rating should be shown even for queries
which cannot be resolved.

First, the straightforward queries:

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50. NAME=Paul Barker, OU=Computer Science, O=University College
    London, C=GB

51. NAME=Paul Barker, OU=Computer Science, O=UCL, C=GB

52. NAME=Barker, OU=Computer, O=UCL, C=GB

53. NAME=Barker, O=UCL, C=GB

54. NAME=p barker, O=university college, C=GB

55. NAME=paul b, OU=cs, O=university college, C=GB

More difficult queries:

56. NAME=p b, O=university college, C=uk

57. NAME=Paul Barker, OU=Computer Networking, O=london college, C=GB

58. NAME=Paul Baker (sic), OU=cs, O=ucl, C=Britain

59. NAME=p baker (sic), O=UCL, C=England

60. NAME=Paul Barker, OU=Directories, O=london, C=United Kingdom

Other general questions:

61. Will the DUA attempt a query of the form ``Find all the Smiths in
    Britain''?  .....................................................

    If so, does it do it by:

   (a)  A single query under the country node?  .....................

   (b)  Multiple queries under all organisation nodes?  .............

62. Does the DUA allow ``hands-off'' querying whereby the details of a
    query may be entered in one go, and the DUA attempts to resolve
    the query without any further user intervention?  ...............

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13  International Languages

63. Does the DUA offer multi-lingual support.  If so:  ..............

   (a)  State which languages are already supported [1 per language up
        to a maximum of 3] ..........................................
     ................................................................

64. Can the DUA handle national language characters not found in
    PrintableString?  [2 if yes] ....................................

14  User Friendliness

65. Is run-time help available?  [2 if yes] .........................
    If so:

   (a)  Is context-sensitive help available?  [1 if yes] ............

   (b)  How many screens/windows?  ..................................

   (c)  How many bytes of help information?  [2 if more than 5 Kbytes
        of text, 1 if more than 3 Kbytes] ...........................

66. Are the error messages terse renderings of the X.500 service
    errors, or user-friendly!?  As an example, provide the error
    message displayed to the user if an administrative limit is
    exceeded.  [2 if user-orientated, 1 if administrator-orientated, 0
    if no message at all] ...........................................
 ....................................................................
 ....................................................................

67. If modify operations are provided, is there support for editing
    the attributes correctly with the appropriate syntax (e.g., does
    the DUA guide the user that addresses are of up to 6 lines of up
    to 30 characters; what support is given for entering distinguished
    names) [2 for postal address support, 2 for DN support, 1 for any
    other support] ..................................................

68. Is the user allowed to see what sort of entries are in the
    Directory if they are unable to find the entry they are looking
    for?  [1 if yes] ................................................

Barker                  Expires 23 March 1993                  Page 18



INTERNET--DRAFT               DUA Metrics               September 1992

69. Does the DUA allow automatic following of attributes with DN
    values, such as seeAlso and roleOccupant?  [1 if yes]............

15  Operational Use

The DUA exists.  But is there any evidence to suggest that it is a
usable tool?

70. Is this DUA widely in use?  [5 if used by more than 20 orgs, 3 if
    by more than 10 orgs, 2 if by more than 5 orgs, 1 if used
    operationally to provide a service anywhere] ....................

   (a)  Is this DUA in use anywhere in the COSINE/Internet Pilot?  ..
     ................................................................

   (b)  Is this DUA in use in any other major pilot?  ...............

   (c)  Is this DUA in use anywhere else operationally?  ............

71. Has this DUA been assessed by groups outside of the software
    developers or providers?  .......................................

72. If so, are the assessments public?  Please provide copies of these
    assessments if they are available ...............................

Barker                  Expires 23 March 1993                  Page 19



INTERNET--DRAFT               DUA Metrics               September 1992

__________________________________________________________
|_____Section____||_____Points____||______________________|
|No._|Description_|Maximum_|Scored||______________________|_
|    |           |        |       ||                       |
|__2_|Gen_Info____|__10___|_...___||__________n/a_________ |
|    |           |        |       ||                       |
|__3_|Conf_to_OSI_|__15___|_...___||__________n/a_________ |
|    |Conf to Res |       |       ||                       |
|__4_|Comm_stds___|__10___|_...___||__________n/a_________ |
|    |           |        |       ||                       |
|__5_|Gen_Style___|__10___|_...___||__________n/a_________ |
|    |           |        |       ||                       |
|__9_|Disp_Res____|__10___|_...___||__________n/a_________ |
|    |           |        |       ||                       |
|_10_|Assoc_hand._|__15___|_...___||__________n/a_________ |
|    |           |        |       ||                       |
|_11_|Man_cap_____|__10___|_...___||__________n/a_________ |
| 12 |Query res   |       |       |Search |No.  of other |
|    |           |        |       |Stones |entries found |
|____|Q._50_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._51_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._52_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._53_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._54_______|__2____|_...___|_...___|:_...._....___|_

|    |           |        |       |       |              |
|____|Q._55_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._56_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._57_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._58_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._59_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       |       |              |
|____|Q._60_______|__2____|_...___|_...___|:_...._....___|_
|    |           |        |       ||                       |
|_13_|Int_Lang____|__5____|_...___||__________n/a_________ |
| 14 |User-fr     |       |       ||                       |
|    |           |        |       ||                       |
|    |Query DUA  |   10   | ..... ||          n/a          |
|    |           |        |       ||                       |       Page 20
|____|Modify_DUA_|___15___|_...___||__________n/a_________ |
|    |           |        |       ||                       |
|_15_|Op_use______|__5____|_...___||__________n/a_________ |
                        Table 1:  DUA Metrics