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Designing a TCP/IP call from a Web server

My shop uses TS 1.3 with CICSPLEX. I would like to design a TCP/IP call from a Web server into TS 1.3 via a TOR to AOR with CICSPLEX and to pass a 32K area back and forth between server and CICS.

I am told by my systems people that this will not work because CICSPLEX requires the task to be attached to a terminal and that the TCP/IP call will not be viewed by CICSPLEX as terminal attached. I have done calls (in other shops) from a VB program, passed a 32K area into a CICS COMMAREA and back with success. I've just never had the CICSPLEX thrown in.

I don't believe IBM/CICS would cut itself off from TCP/IP like the systems guys are telling me. Help!

What you want to do seems perfectly reasonable to me and very doable.

There seems to be a communication mismatch in how the flow triggers a transaction. This transaction will be, as noted by your technical chappies/esses, running non-terminal. So, if what you want to run as a result of the TCP/IP flow assuming it is being run on a terminal-based facility, then it won't work. But you can always use FEPI (which I wrote or CICS) as an intermediate terminal emulator if so required.

Have a look in the April issue of Xephons CICS Update and read my article about how to configure CICS to support a functional arrangement such as you seem to require.

If by CICSPLEX you mean a bunch of CICS regions managed by CICSPLEX/SM, then the only relevant bit of it relating to non-terminal based transactions initiated via TCP/IP would be the load balancing or routing functions. I'd check to see if this is the concern.

I'd implement this operation using the MVS sockets interface for CICS and write myself a listener specifically for this function. This can then use CPSM facilities for best performance.

What you are going to end up with is a flow into a CICS region that starts up a transaction that gets the given socket. This transaction instance will be in the same region as the socket. Perhaps this is the ambiguous mismatch. This transaction should then either wholly reside in that same region or use XC LINK SYSID to run the function elsewhere (probably a good arrangement). Once this real work has been done then the reply is extracted out of the Commarea and sent back down the socket, and so on.

If you want to use more than 32K in a Commarea, look at the library section on the CICS Web site for my Big Commarea paper. You will want to use a shared VSAM repository.

Robert Harris
CICS Technical Strategist -- CICS expert at Search390.com

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