Establishing LU-SSCP Sessions on the HP 3000

For a dependent LU on the HP 3000 to communicate with another dependent LU, it must first have a session with the SSCP host SSCP, establishing establishing on the host system. Each LU-SSCP session is managed by SNA Transport. Figure 4-2 shows LU-SSCP session establishment with SNA Transport acting as the LU service manager. The SSCP checks the configuration on the host for the LUs defined for the HP 3000 node. The SSCP will attempt to activate each defined LU by sending an ACTivate LU (ACTLU) request request. (An independent LU does not need a corresponding LU-SSCP session to help in establishing an LU-LU session, so the sequence below does not apply for an independent LU.)

          IBM Host                        HP 3000 (T2.0 Node)



   For every LU configured on

      host, SSCP sends

      ACTivate LU request          ACTLU

                                - - - - - ->



                                            SNA Transport checks configuration

                                               file for LUs; sends positive

                                               responses only for LUs 

   found

                                               in configuration file

                               (+ response)

                               <- - - - - - 



                      (LU-SSCP session established)

Once an LU-SSCP session is established, a dependent LU-LU session can be initiated. The "Startup and Shutdown" chapter in the Node Manager's Guide for each SNA service contains an explanation of how LU-LU sessions are established and terminated for that service.