9 August 1993
 Meeting of Experts on Data Elements
 and Automatic Data Interchange (GE.1)
 (Forty-eighth session, 21-22 September 1993
 Item 4 of the provisional Agenda)


* * *

 Transmitted by the Directory Reference Group (DRG),
 the Team of Technical Advisors (TTA) and the Syntax Development Group
(SDG) *

 *     The present document is reproduced in the form in which is was 
       received by the secretariat.


ACTION: FOR APPROVAL at the GE.1 meeting, 1993-09-21/22, agenda item **
 1.   As a result of the approval at the March 1993 session of WP.4 of
      the new directory issue cycles (see TRADE/WP.4/GE.1/91, paragraph
      43.4) and, in particular, the adoption of the concept of Working
      and Standard Directories, there has been an impact on version and
      release procedures.
 2.   This paper suggests how, within a message, the 'version and
      release data elements' within UNH can be directly used to
      identify the type of directory in which the message was published
      in addition to the directory issue.
 3.   Up until now, in the UNH segment data element 0052 has been used
      to identify the status of the message type and data element 0054
      to indicate the directory type and issue. This system, which 
      posed problems in the past, is even less adequate under the new
      directory issue criteria.
      With this in mind, the Syntax Development Group (SDG) is in the
      process of revising the UNH service segment fully to meet the
      requirements of the user community. However, it is not likely 
      that the results of this work will be approved before 1995, 
      thus an interim solution is needed to solve the immediate 
 4.   It is expected that the SDG solution will provide a means for
      separate identification of code list directories. However, until
      the syntax is able to accommodate this, we would propose the
      incorporation of the most recent Consolidated Code List (CCL), at
      the time of publication, into both the Working and Standards
      directories as the code directory.
 5.   The report of the 47th session of GE.1 (TRADE/WP.4/GE.1/91)
      identified in paragraph 43.4 ii. for recommendation to WP.4 that
      "From April 1993, the concept and philosophy put forward in 
      the ESD report of a Working directory and of a Standards 
      directory should be adopted;" This was reflected in the report
      of the 37th session of WP.4 (TRADE/WP.4/183) in paragraph 31. as 
      the need "To agree on the terminology of Standards and Working 
      directories to replace the current terminology of Status 2 and 
      Status 1 (trial) directories;".
 6.   In reviewing the terminology to be adopted, it becomes 
      apparent that:
      i)   the directory containing "Recommendations" (i.e. 
           United Nations Standard Messages also referred to as 
           Status 2 messages) should be referred to as the 
           "Standards" directory;
      ii)  the directory containing "Draft recommendations" 
           (i.e. Status 1 messages for trial and all Status 2 messages
           in their latest form) should be referred to as the 
           "Draft" directory, as this corresponds best to its
           actual contents and current, understood, practice in most 
           standard organizations; and
       iii) the day to day work-in-progress is applied to the
           Maintenance Database, which comprises the Standards and 
           Draft directories, plus messages under development (i.e. 
           Status 0 messages), plus all related Data Maintenance 
           Requests (DMRs). In the past, it was from this maintenance 
           database that "Work Books" were derived. 
           It would therefore, be misleading to call any directory 
           except the one held in the Maintenance database (which is 
           never published except in "Workbooks") a Working 
 7.   The key Version and Release issue is how to indicate the
      publication of multiple directories of the same type within one
      year. Such identification can only, within the current UNH 
      segment, utilize two fields - the above mentioned 0052 and 0054.
      It is therefore proposed that data element 0052 be used to show 
      the directory type and data element 0054 be used to indicate the
      directory issue. The data to be used in these data elements 
      would be as follows:
         Directory Type      0052      0054
         Status    0         0         Document Revision Number
         Draft     D         YYA
         Standard  S         YYA
 YY = Year
 A  = Directory issue within the year shown by an alphabetic
      sequential indicator commencing with A for the first
      issue of a directory type within a year.
             a)  with regard to data element 0052 this is a significant
                 departure from current usage where 0052 used to 
                 contain the MESSAGE's STATUS and NOT the DIRECTORY 
             b)  Status 0 messages are not in a directory, however, 
                 this is the information to be shown in the areas on 
                 the boilerplate cover page corresponding to the 
                 above version/release information.
 8.   Using the proposed solution, the data elements 0052 and 0054 in 
      the UNH segment are envisaged to be used as shown in the 
      following example:
                                              Message  DE   DE
      Directory                      Acronym  Type     0052 0054
      1st standards directory, 1993  S.93A    CREADV   S    93A
      1st draft directory, 1993      D.93A    CREADV   D    93A
      1st draft directory, 1994      D.94A    CREADV   D    94A
      2nd draft directory, 1994      D.94B    CREADV   D    94B
      1st standards directory, 1994  S.94A    CREADV   S    94A
      (Note that the suggested acronym is a shorthand means of
      referring to the directory in question. The acronym
      concatenates the data in elements 0052 and 0054.)
 9.   The proposed solution allows for the identification of a 
      directory within which the message being transmitted is found. 
      Once the directory is known, all of the information required 
      for the processing of that message, for example the segment 
      structures etc, can be determined. However, the proposed 
      solution does not allow the possibility, in the case of a 
      message within a draft directory, to determine whether that 
      message has attained status 2.
 10.  To provide the information regarding message status, it is 
      proposed that the message indexes found in the directory set be
      extended to include a message status column to indicate whether 
      a message is status 1 or 2.
 11.  In addition, it is proposed that a message revision number be 
      shown as part of the message index, to indicate changes in the 
      message boilerplate (including the structure). When a change 
      occurs in a message's boilerplate or structure between directory
      publications, the revision number would increment by one. This 
      would allow message implementors to immediately identify changes 
      which could affect their applications.
 12.  This means that a message appearing in both the Draft Directory
      and the Standards Directory will share a sequential message 
      revision number, which will only change when there has been a 
      change to the message in question.
 13.  The following is an example of message index layout for the 
      index by message type code, using a sample of entries from the
      92.1 directory set.  The index will be a separate file in the
      directories circulated by the UN/ECE, and the example index 
      shown would be that for a Draft Directory:
        Code   Name                                Status   Revision
      + BANSTA Banking Status Message               1         1
        BAPLIE Bayplan - occupied and empty         1         3
        BAPLTE Bayplan/Stowage Plan Total Numbers   1         3
      + CONDPV Direct Payment Valuation Message     1         1
      * CREADV Credit Advice Message                2         5
      * INVOIC Invoice Message                      2         7
        "+" indicates that the message is appearing for the
        first time in the directory;
        "*" indicates that the message has changed from its 
         previous form;
            Where no symbol is shown in front of the message type
            identifier, the message is unchanged from its previous 
            The "Status" and "Revision" columns 
            show not only what will appear in the index for the 
            directory, but also what will be shown on a paper copy 
            of the message.
            The example uses fictitious revision numbers which are 
            shown as a guide only.  The actual revision numbers for 
            each of the messages will have to be determined in 
            consultation with the message design groups.
            An important point which will need to be considered by
            message design groups, is what constitutes a 
            "change" to a message which would result in 
            the revision number being incremented by one?
            This document suggests that there only two types of change
            which fall into this category:
            i)   where a message has its structure changed as a result
                 of a "Message Structure" Data Maintenance 
                 Request being approved under the procedures;
            ii)  when a message design group decides to take advantage
                 of a change to a segment used by one of its messages,
                 by amending the boilerplate for the message to reflect
                 the change.
 14. As the above example shows, the concept of Status 1 and Status 2
     messages WILL continue under the new system of Draft and 
     Standards Directories. Message progression should, therefore, 
     continue as previously: from Status 0 to Status 1 and,
     ultimately, to Status 2. In essence, Draft Directories may 
     contain Status 1 messages and Status 2 messages, whereas Standards
     directories shall only contain messages which have progressed to 
     United Nations Standards Messages (Status 2). (Refer to DRG 
     document on Directories Progression.)
     Issues List
 Issue 1:        Impact on DIRDEF
 Description:    The DIRDEF message, which is due for presentation at
                 the September 1994 Session of GE.1, has not been 
                 designed to take into consideration the need for 
                 transmitting Message Revision Numbers as shown above.
                 If the proposal for Message Revision numbers is 
                 adopted then the DIRDEF message will require minor 
                 modification. The addition of the Message Status 
                 column to the index may also impact DIRDEF.
 Keywords:       DIRDEF modification,
                 Message Revision Number,
                 Message Status Column,
                 Directory Type
 Originator:     Directories Reference Group (DRG); Team of Technical
                 Advisers (TTA); Syntax Development Group (SDG).