Subject: Changes to the DLUR specification - status & update

From: "Ed Tremblay (254-5515)" <[email-masked]>
Date: Fri, 30 Jul 93 09:13:55 EDT

In my last note on this subject I listed 12 items as changes to the
DLUR document.  What follows is the status of those changes as well as
some new items:

1) through 11) have been incorporated into what will be dlur2.ps when
it is released.

12) Here is a rough draft of the addressing information - please review
    this and let me know by 8/9 whether this section is acceptable, and
    if not, what additional information is needed here:

    6.1.3  Addressing Per Stage
    ---------------------------

    Much of this is derived from the ASM (Address Space Manager) chapter
    in the APPN Architecture Reference (pages 6-5 through 6-7).

    LFSIDs are the addresses carried in FID2 THs; these addresses have
    three parts: SIDH (1 byte), SIDL (1 byte), ODAI (1 bit).

    6.1.3.1  SSCP-PU and SSCP-LU sessions
    -------------------------------------

    ********       ********       ********       ********       *******
    * DLUS *-------*  NN  *-------*  NN  *-------* DLUR *-------*PU/LU*
    ******** stage ******** stage ******** stage ******** stage *******
               1              2              3              4

    |   |   |   |   |   |   |   |   |      |
    |   |   |   |   |   |   |CVs|   |      |
    |   |   |   |THb|RHb|RUb|---|   |      |
    |   |   |GDS|---------------|CVs|FQPCID|
    |THa|RHa|------------------------------|
    ----------------------------------------

    <-------------------------------------->  flows on stages 1, 2, 3

                <--------------->             flows on stage 4

    SSCP-PU       THa           THb
    --------------------------------------
     SIDH     X'02'-X'FE'      X'00'
     SIDL     X'00'-X'FF'      X'00'
     ODAI     negotiated         0
              during XID
              exchange

    SSCP-LU       THa           THb
    --------------------------------------
     SIDH     X'02'-X'FE'      X'00'
     SIDL     X'00'-X'FF'   X'01'-X'FF'
     ODAI     negotiated         0
              during XID
              exchange

    At the DLUR and DLUS nodes, the FQPCID is used to identify the
    proper PU.

    The SIDL value in THb is used to identify the proper LU.

    LFSIDs for THa are independently set for each stage and for each
    direction; in the configuration shown, there will be six different
    THa LFSIDs for a message sent from DLUS to DLUR and back to DLUS.

    6.1.3.2  LU-LU sessions
    -----------------------

    ********       ********       ********       ********       *******
    * PLU  *-------*  NN  *-------*  NN  *-------* DLUR *-------*PU/LU*
    ******** stage ******** stage ******** stage ******** stage *******
               1              2              3              4

                |   |   |   |   |
                |   |   |   |CVs|
                |THb|RHb|RUb|---|
                |---------------|

                <--------------->             flows on stages 1, 2, 3, 4

     LU-LU
      THb    stages 1, 2, 3   stage 4
    --------------------------------------
     SIDH     X'02'-X'FE'      X'01'
     SIDL     X'00'-X'FF'   X'01'-X'FF'
     ODAI     negotiated         0
              during XID
              exchange

    For stages 1, 2, and 3, LFSIDs for THa are independently set for
    each stage and for each direction; in the configuration shown,
    there will be six different THb LFSIDs for a message sent from PLU
    to DLUR and back to PLU.  For stage 4, SIDL should be the same value
    used for the SIDL in THb for that LU's SSCP-LU session.

13) Usually error checking follows main path in product implementation
    and testing.  Recently more and more sense code questions have
    come up and will no doubt continue throughout testing.  I've been
    soliciting products for sense codes that have been used that are not
    currently included in the document.  I'm going to create two new
    sections (5.8 and 6.5) to include these sense codes and others as
    they are discovered or added.

    Initially section 5.8 will include:

      * DLUR products will have the option to limit the number of
        concurrently active CP-SVR pipes (what number will be selected
        as the limit will also be a product option).  If a limit is
        implemented and reached, any attempts to activate additional
        CP-SVR pipes will be rejected by sending an UNBIND request with
        sense code X'0812 0000'.

      * If the Receive_Encap_Msg_TP is attached and the GDS variable
        received is not X'1500', the DLUR will send an UNBIND request
        with sense code X'1001 0000'.

    Initially section 6.5 will include:

      * Any PIU request encapsulated in a GDS X'1500' which does not
        include a CV X'60' will be discarded.

      * Any ACTPU request encapsulated in a GDS X'1500' which does not
        include a CV X'46' will be rejected with a X'0806 0000' sense
        code.

      * Any ACTPU request encapsulated in a GDS X'1500' which does not
        include a CV X'51' when one is expected (first ACTPU after the
        CP-SVR pipe is activated) will be rejected with a X'086C 5100'
        sense code.