CICS distributed program link

This section describes CICS® distributed program link (DPL).

Overview of DPL
CICS distributed program link enables CICS application programs to run programs that are in other CICS regions by shipping program-control LINK requests.
Statically routing DPL requests
Static routing means that the location of the server program is specified at design time, rather than at run time. DPL requests for a particular remote program are always routed to the same server region. Typically, when static routing is used, the location of the server program is specified in the PROGRAM resource.
Dynamically routing DPL requests
Dynamic routing means that the location of the server program is decided at run-time, rather than at design time. DPL requests for a particular remote program may be routed to different server regions. For example, if you have several cloned application-owning regions, you may want to use dynamic routing to balance the workload across the regions.
Daisy-chaining of DPL requests
Statically-routed DPL requests can be daisy-chained from region to region.
Limitations of DPL server programs
A DPL server program cannot issue the following types of commands.
Intersystem queuing
If the link to a remote region is established, but there are no free sessions available, distributed program link requests may be queued in the issuing region. Performance problems can occur if the queue becomes excessively long.
Examples of DPL
This section gives some examples to illustrate the lifetime of the mirror transaction and the information flowing between the client program and its mirror transaction.

Parent topic: Getting started with intercommunication

Last updated: Friday, 18 December 2020 08:52