KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q198179: Enabling an APPC/CPIC Program to Use Persistent Verification

Article: Q198179
Product(s): Microsoft SNA Server
Version(s): WINDOWS:3.0 SP3,4.0,4.0 SP1
Operating System(s): 
Keyword(s): 
Last Modified: 13-JUN-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft SNA Server, versions 3.0 SP3, 4.0, 4.0 SP1 
-------------------------------------------------------------------------------

SUMMARY
=======

Microsoft SNA Server 3.0 Service Pack 3 and later versions include support for
LU6.2 "persistent verification" as described in the following Knowledge Base
article:

  Q180866 Persistent Verification Support for APPC Sessions

In order for an application to make use of SNA Server persistent verification
support, the application must do the following:

- An APPC application must set security = AP_SAME, and set the user_id and pwd
  fields on every call to the [MC_]ALLOCATE verb.

- A CPIC application must set conversation_security_type = XC_SECURITY_SAME,
  and set security_user_id and security_password fields prior to every call to
  the CMALLC (Allocate) function.

MORE INFORMATION
================

Persistent verification (PV) eliminates the need to provide a user ID and
password on each Attach during multiple conversations between a user and its
partner at a remote LU. The user is verified once during a sign-on process
during its initial conversation over an LU6.2 session between an LU/LU pair, and
remains verified until the user is signed off by the remote LU, or if all
sessions between the LUs are ended.

In order for persistent verification to be used, the host system must indicate
support within its BIND command or response, by setting the following option:

  Byte 23, Bit 7 persistent verification capability must be set to 1 (ON):
  (Persistent Verification indicator is supported on incoming FMH-5s)

Note that SNA Server does not set this bit, because SNA Server only supports the
sending of FMH-5 Attach requests with persistent verification. SNA Server does
not support incoming FMH-5 Attaches which have persistent verification set.

If SNA Server detects that the remote system supports persistent verification (as
indicated in the host BIND message), then the APPC or CPIC application can take
advantage of persistent verification by setting security = SAME, and by
providing a user ID AND password on every allocate request. SNA Server then
implements PV by maintaining a PV sign-on user list associated with each Remote
APPC LU as follows:

- If a client allocate request is received and the user is not in the PV user
  sign-on list, SNA Server adds the user to its sign-on user list, sets Byte 4
  Bit 1-2 (persistent verification indicator) to "01", indicating "sign-on
  requested", and includes the user ID and password security vectors in the
  FMH-5 Attach.

- If a client allocate request is received and the user is found in the sign-on
  list, SNA Server sets Byte 4 Bit 1-2 (persistent verification indicator) to
  "10" indicating "already signed on", and includes the user ID only in the
  FMH-5 Attach, but does not include the password vector.

As mentioned above, SNA Server removes a user from its PV sign-on list when one
of the following conditions occurs:

- If the remote system sends a PV Sign-Off request to SNA Server and indicates
  the user. The remote system initiates an LU6.2 conversation to the SNA Server
  Sign-Off TP (TP name = X'06F3F0F0'), and indicating the user name in the
  Sign-Off GDS X'1220' message.

- If all sessions end between the SNA Server LU and remote LU. This can occur
  if the connection fails or if all sessions are unbound.

There is no way to view the SNA Server PV sign-on list, although this is under
consideration for a future release of SNA Server.


REFERENCES
==========

IBM documents the format of the SNA BIND command and FMH-5 Attach requests in
the following IBM reference:

  Title: Systems Network Architecture Formats
  IBM Document Number GA27-3136-14

For more information about persistent verification, please see the following IBM
reference:

  Title: SNA LU 6.2 Peer Protocols
  IBM Document Number: SC31-6808-02


Additional query words:

======================================================================
Keywords          :  
Technology        : kbAudDeveloper kbSNAServSearch kbSNAServ400 kbSNAServ300SP3 kbSNAServ400SP1
Version           : WINDOWS:3.0 SP3,4.0,4.0 SP1
Issue type        : kbinfo

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.