Defining an ISC TCP/IP link in CICS

An ISC TCP/IP link is configured in CICS® as an IP interconnectivity (IPIC) connection by two CICS resource definitions: an IPCONN resource and a TCPIPSERVICE resource.

The CICS IPCONN resource defines the attributes that are required for CICS to send messages on an IPIC connection. From the CICS perspective, the IPCONN statement defines the outbound attributes of an IPIC connection.

One IPCONN resource is required for each parallel session. In CICS, the IPCONN resources can be created dynamically with the CICS autoinstall program or you can define them yourself.

In the IPCONN resource definition, the following parameters must match values that are specified in IMS:

IPCONN(ipconnname) must match either the user name that is specified on the IMS /OPNDST command or, for statically defined ISC TCP/IP terminals, the NAME keyword on a SUBPOOL IMS system definition macro.
HOST must match the host name of IMS Connect that is specified on the HOSTNAME keyword in the TCPIP configuration statement in the IMS Connect HWSCFGxx member of the IMS.PROCLIB data set..
PORT must match the value that is specified on the CICSPORT parameter in both the RMTCICS and TCPIP configuration statements in the IMS Connect HWSCFGxx member of the IMS.PROCLIB data set. IMS Connect receives messages from CICS on this port.

The CICS TCPIPSERVICE resource defines the attributes that are required for CICS to receive messages on an IPIC connection. From the CICS perspective, the TCPIPSERVICE resource defines the inbound attributes of an IPIC connection.

In the TCPIPSERVICE resource definition, the following parameters must match values that are specified in the IMS:

HOST must match the host name of IMS Connect that is specified on the HOSTNAME keyword of the TCPIP configuration statement.
PORT must match the value that is specified to IMS Connect on the PORT parameter of the ISC configuration statement.

The following example shows the definitions for the CICS IPCONN and TCPIPSERVICE resources.

DELETE GROUP(TCPIPGRP)
DEFINE TCPIPSERVICE(TSA)
       PORT(23456)
       PROTOCOL(IPIC)
       GROUP(TCPIPGRP)

DEFINE IPCONN(LU6SPA)
       APPLID(LU6SPA)
       AUTOCONNECT(YES)
       HOST(XYZ.EXAMPLE.COM)
       PORT(1111)
       SENDCOUNT(5)
       RECEIVECOUNT(5)
       TCPIPSERVICE(TSA)
       GROUP(TCPIPGRP)

DEFINE IPCONN(LU6SPB)
       APPLID(LU6SPB)
       AUTOCONNECT(YES)
       HOST(XYZ.EXAMPLE.COM)
       PORT(3333)
       SENDCOUNT(5)
       RECEIVECOUNT(5)
       TCPIPSERVICE(TSA)
       GROUP(TCPIPGRP)

DEFINE IPCONN(LU6SPC)
       APPLID(LU6SPC)
       AUTOCONNECT(YES)
       HOST(XYZ.EXAMPLE.COM)
       PORT(3333)
       SENDCOUNT(5)
       RECEIVECOUNT(5)
       TCPIPSERVICE(TSA)
       GROUP(TCPIPGRP)

DEFINE IPCONN(USER01)
       APPLID(USER01)
       AUTOCONNECT(YES)
       HOST(XYZ.EXAMPLE.COM)
       PORT(6666)
       SENDCOUNT(5)
       RECEIVECOUNT(5)
       TCPIPSERVICE(TSA)
       GROUP(TCPIPGRP)

DEFINE IPCONN(USER02)
       APPLID(USER02)
       AUTOCONNECT(YES)
       HOST(XYZ.EXAMPLE.COM)
       PORT(6666)
       SENDCOUNT(5)
       RECEIVECOUNT(5)
       TCPIPSERVICE(TSA)
       GROUP(TCPIPGRP)

DEFINE IPCONN(USER03)
       APPLID(USER03)
       AUTOCONNECT(YES)
       HOST(XYZ.EXAMPLE.COM)
       PORT(7777)
       SENDCOUNT(5)
       RECEIVECOUNT(5)
       TCPIPSERVICE(TSA)
       GROUP(TCPIPGRP)

DEFINE IPCONN(USER04)
       APPLID(USER04)
       AUTOCONNECT(YES)
       HOST(XYZ.EXAMPLE.COM)
       PORT(7777)
       SENDCOUNT(5)
       RECEIVECOUNT(5)
       TCPIPSERVICE(TSA)
       GROUP(TCPIPGRP)

DEFINE TRANSACTION(SR1A)
       PROGRAM(IMSSRT1A)
       GROUP(DFHPPTDR)

DEFINE PROGRAM(IMSSRT1A)
       GROUP(DFHPPTDR)
       LANGUAGE(COBOL)

ADD GROUP(TCPIPGRP) LIST(DRVRLIST)