(Message inbox:39)Replied: Thu, 23 Nov 89 11:49:43 +0000Replied: John Dyer <NJIN04@uk.ac.rutherford.gec-b>Replied: ISO-XWINDOWS@uk.ac.rutherfordReplied: "x3h3.6" <x3h3.6%edu.mit.lcs.expo@uk.ac.nsfnet-relay>Received: from vs6.cs.ucl.ac.uk by pyr1.Cs.Ucl.AC.UK   via Ethernet with SMTP           id aa28231; 23 Nov 89 11:03 GMTReceived: from gec-b.rutherford.ac.uk by vs6.Cs.Ucl.AC.UK   via Janet with NIFTP           id aa04229; 23 Nov 89 10:58 WETVia:   UK.AC.RUTHERFORD.GEC-B ;  Thu, 23 Nov 89 10:58 GMT        (V39 at UK.AC.RUTHERFORD.GEC-B)From:    John Dyer <NJIN04@uk.ac.rutherford.gec-b>To:      ISO-XWINDOWS@uk.ac.rutherford,          "x3h3.6" <x3h3.6%edu.mit.lcs.expo@uk.ac.nsfnet-relay>Date:    Thu, 23 Nov 89 10:58 GMTSubject: Proposed Transport Annex to X DSEMessage-Id: <23 NOV 1989 10:58:09 NJIN04@UK.AC.RUTHERFORD.GEC-B> Here is the revised Appendix to the X Window System DSE. This version is are write of the previuos version, but has been changed to accommodate the use of any Transport Class (ie TP0 through to TP4). The major changes involve the NON use of user data fields in T-CONNECT and T-DISCONNECT.John DyerJoint Network Team--------------------------------------------------------------------------------                          DRAFT (v2.0) PROPOSED APPENDIX xx                              X Windows Mapping to OSI        This  appendix  should  be  treated as an integral part of (the ANSI      standard X3H3.6/yy-nnnn).       This  appendix defines the mapping of the X Windows protocol defined      in  (the  ANSI  standard  X3H3.6/yy-nnnn)  onto  the   communication      services   provided   by  the  Open  Systems  Interconnection  (OSI)      standards. (The OSI reference model is described in  ISO  7498).  It      shows  not  only the mappings onto the OSI communication primitives,      but also how the registration and addressing requirements of  the  X      Windows protocol are handled for OSI.       This  appendix consists of two sections, section A.1 for the mapping      of X Windows functions onto OSI service primitives and  section  A.2      for the X Windows registration requirements.       This appendix references ISO 8072 (Transport Service Definition) and      uses the notation and conventions which are contained in sections 3,      4 and 5 of that document.        A.1 Mapping X Windows Functions to OSI Service primitives       This  section  specifies  the OSI service primitives used to support      the X Windows functions.       The X Windows requirements on the communication mechanism which have      been considered in choosing this OSI service are :       a)  the   asynchronous   nature  of  the  way  X  Windows  uses  the          communication mechanism,       b)  connection oriented communication,       c)  reliable communication service,       d)  full duplex communication,       e)  process addressing, i.e. ability to select a particular X Windows          server,       f)  the  supporting OSI functionality that most closely matches that          for which X Windows was written,       g)  efficiency,       h)  interworking with existing implementations.        These  requirements are met using a connection oriented TWS (two way      simultaneous, i.e.  full  duplex)  OSI  Transport  Layer  connection      providing a service direct to client and server.       A.1.1 Transport Connection Establishment and Termination       A.1.1.1 Connection Establishment  |    The X Window function OPEN DISPLAY (see Part 1, section 7.6.1 of the |    ANSI  standard  X3H3.6/yy-nnnn) establishes a connection between the |    client and server. For operation over  OSI,  the  transport  service |    connection  is made by T-CONNECT, however the X Windows OPEN DISPLAY |    function is not carried in the T-CONNECT User-Data parameter, but in |    the User-Data of the subsequent T-DATA.                                  The  COTS  T-CONNECT  service  is  defined  in  section 12 and the      T-CONNECT parameters are listed in table 5 of ISO 8072.        A.1.1.1.1 COTS T-CONNECT parameters and OPEN DISPLAY  |    The  T-CONNECT  parameter  values for support of OPEN DISPLAY are as |    specified in table 1. An explanation of the use  of  each  parameter |    follows the table.  |    Table 1 -- T-CONNECT Parameter Values to support OPEN DISPLAY         +-------------------------------------+-----+-----+-----+-----+        |      T-CONNECT   Parameter Name     | Req | Ind | Rsp | Cnf | |      +-------------------------------------+-----+-----+-----+-----+ |      | Called Address                      |  X  | X(=)|     |     | |      +-------------------------------------+-----+-----+-----+-----+ |      | Calling Address                     |  X  | X(=)|     |     | |      +-------------------------------------+-----+-----+-----+-----+ |      | Responding Address                  |     |     |  X  | X(=)| |      +-------------------------------------+-----+-----+-----+-----+ |      | Expedited Data Option               |  N  |  N  |  N  |  N  | |      +-------------------------------------+-----+-----+-----+-----+ |      | Quality of Service                  |  N  |  N  |  N  |  N  | |      +-------------------------------------+-----+-----+-----+-----+ |      | User-Data                           |  N  |  N  |  N  |  N  |        +-------------------------------------+-----+-----+-----+-----+  |    Key:  X: Mandatory Parameter           (=): The value of this parameter is indentical to the value               of the corresponding parameter of the preceding primitive.  |          N: Not used by X Windows - where the parameter needs a value |             as a mandatory requirement of the transport service it may  |             take a default value.   |    Addresses:  The paramaters which  take  address  values all refer to |        TSAPs.  These addresses  are  unique  within  the  scope of TSAP  |        addresses.       Called  Address: This mandatory parameter identifies the application          process which is the X Windows server to which the T-CONNECT  is          being  sent.  It  conveys  the  address of the TSAP to which the          transport connection is to be established.       Calling Address: This mandatory parameter identifies the application          process which is the X Windows client. It conveys the address of          the TSAP from which the transport connection has been requested.       Responding  Address: This mandatory parameter conveys the address of          the TSAP to which the transport connection has been  established          and is identical to the Called Address parameter.       Expedited  Data  Option:  X  Windows  deals  with  all communication          requests serially and does not have the notion of  urgent  data.          The  Expedited Data Option therefore always takes the value 'not          selected'.       Quality  of  Service: This mandatory parameter consists of a list of          parameters specifying the quality of service for  the  transport          connection.  The  parameters  are  defined  in section 10 of ISO          8072.           Note:  This  parameter  is  currently  not  widely  used  by OSI          applications and is not used by X Windows.  |    TS  User-Data:  This  mandatory parameter is not used by X Windows OPEN |        DISPLAY.                                  A.1.1.2 Connection Release  |    A.1.1.2.1 COTS T-DISCONNECT and CLOSE DISPLAY       The  X  Window  function  CLOSE  DISPLAY  is  used  to terminate the |    connection from the client in an  orderly  fashion.  The  X  Windows |    function  CLOSE  DISPLAY  is  mapped  to  T-DATA  User-Data  and the |    transport connection terminated by  a  subsequent  T-DISCONNECT.      |    Table 2 T-DISCONNECT Parameter Values to support CLOSE DISPLAY                 +----------------------------------+-----+-----+                |   T-DISCONNECT Parameter Name    | Req | Ind |                +----------------------------------+-----+-----+ |              | Disconnect Reason                |     |  X  |                +----------------------------------+-----+-----+ |              | User Data                        |  N  |  N  |                +----------------------------------+-----+-----+  |    Key:  X: Mandatory Parameter  |          N: Not used by X Windows - where the parameter needs a value |             as a mandatory requirement of the transport service it may  |             take a default value.        Reason:   The   disconnection  reason  parameter  gives  information          indicating the cause of the transport  connection  release.  The          reason  will  be  one  of  those listed in section 14.2.1 of ISO          8072.  |    User  data:  This mandatory parameter is not used by X Windows CLOSE |        DISPLAY.    |    A.1.1.2.2 COTS T-DISCONNECT and KILL CLIENT  |    The  X  Window  function  KILL  CLIENT  request  from  the server to |    terminate the client immediately is mapped to T-DATA User-Data.  The |    transport  service  connection  being  terminated  by  a  subsequent |    T-DISCONNECT. The T-DISCONNECT parameter values for support of  KILL |    CLIENT are as specified in table 3.        |    Table 3 T-DISCONNECT Parameter Values to support KILL CLIENT                  +----------------------------------+-----+-----+                |   T-DISCONNECT Parameter Name    | Req | Ind |                +----------------------------------+-----+-----+ |              | Disconnect Reason                |     |  X  |                 +----------------------------------+-----+-----+  |              | User Data                        |  N  |  N  |                 +----------------------------------+-----+-----+   |    Key:  X: Mandatory Parameter  |          N: Not used by X Windows - where the parameter needs a value |             as a mandatory requirement of the transport service it may  |             take a default value.       Reason:   The   disconnection  reason  parameter  gives  information          indicating the cause of the transport  connection  release.  The          reason  will  be  one  of  those listed in section 14.2.1 of ISO          8072.  |    User  data:  This  mandatory  parameter is not used by the X Windows |        KILL CLIENT function.        A.1.2 Data Transmission  |    All  of  the  X  Windows functions datstream is to be carried in the |    transport service T-DATA User-Data. This includes the functions OPEN |    DISPLAY, CLOSE DISPLAY and KILL CLIENT specifically mentioned above.       T-DATA has only one parameter as shown in table 4. An explanation of      the use of this parameter follows the table.       Table 4 T-DATA Parameter Values               +-------------------------------------+-----+-----+              |       T-DATA  Parameter Name        | Req | Ind |              +-------------------------------------+-----+-----+ |            | User data                           |  X  | X(=)|              +-------------------------------------+-----+-----+  |    Key:  X: Mandatory Parameter           (=): The value of this parameter is indentical to the value               of the corresponding parameter of the preceding primitive.         User  data:  This mandatory parameter passes all X Windows functions          and datastreams between  X  Windows  clients  and  servers.  For          support  of  X  Windows, the ASN.1 type of this data is EXTERNAL          where the encoding is as  specified  in  Part  2  of  (the  ANSI          standard X3H3.6/yy-nnnn).         A.1.3 Lower Layer Requirements  |    Layers  1  to  3  may  be  any  coordinated set of protocols, either |    connection oriented or connectionless,  capable  of  supporting  the |    Connection Oriented Transport Service.  |    This  appendix  defines  a mapping onto a Transport service which is |    capable of supporting all of the five protocol classes specified  in |    sections 7 to 12 of ISO 8073 (Connection Oriented Transport Protocol |    Specification). It  is  recommended  that  for a Connection Oriented |    Network the appropriate Transport Protocol  Class  is  class  0,  as |    specified in section 8 of ISO 8073.       A.2 Registration, Names and Addresses       A.2.1 Registration       The  registration  requirements for X Windows consist of registering      the names of X Windows servers.       The  resolution  of  names  to  addresses may be handled using local      (e.g.  non-standardized)  mechanisms  or  by  the  use  of  the  OSI      Directory service, see ISO 9594.  |    ***END OF PROPOSED TEXT (JD v2.0 24/10/89)***