The CICS adapter

The CICS adapter connects a CICS subsystem to a queue manager, enabling CICS application programs to use the MQI.

We can start and stop CICS and WebSphere MQ independently, and we can establish or terminate a connection between them at any time. We can also allow CICS to connect to WebSphere MQ automatically.

The CICS adapter provides two main facilities:

In a CICS multiregion operation or intersystem communication (ISC) environment, each CICS address space can have its own attachment to the queue manager subsystem. A single CICS address space can connect to only one queue manager at a time. However, multiple CICS address spaces can connect to the same queue manager.

We can use WebSphere MQ with the CICS Extended Recovery Facility (XRF) to aid recovery from a CICS error.

The CICS adapter is supplied with WebSphere MQ and runs as a CICS External Resource Manager. WebSphere MQ also provides CICS transactions to manage the interface.

The CICS adapter uses standard CICS command-level services where required, for example, EXEC CICS WAIT and EXEC CICS ABEND. A portion of the CICS adapter runs under the control of the transaction issuing the messaging requests. Therefore, these calls for CICS services appear to be issued by the transaction.