Intercommunication facilities

In a multiple-system environment, each participating system can have its own local terminals and databases, and can run its local application programs independently of other systems in the network.

A participating system can also establish links to other systems, and gain access to remote resources. This mechanism allows resources to be distributed among and shared by the participating systems.

CICS® provides the following types of facilities for communicating with other CICS, IMS, or other systems:
  • Function shipping
  • Asynchronous processing
  • Transaction routing
  • Distributed program link (DPL)
  • Distributed transaction processing (DTP)

For more information about the intercommunication facilities that support access to CICS programs and transactions from non-CICS environments, see Interfaces to CICS transactions and programs and Internet, TCP/IP, and HTTP concepts .

These communication facilities are not all available for all forms of intercommunication. The circumstances under which they can be used are shown in Table 1.
Table 1. Support for CICS basic intercommunication facilities, when communicating with other CICS, IMS, APPC, or TCP/IP systems
 
IRC
Interregion
communication
Intersystem
communication
over TCP/IP
Intersystem communication
over SNA
(using ACF/ z/OS® Communications Server)
 
MRO
IPIC
LUTYPE6.2 (APPC)
LUTYPE6.1
Facility
CICS
CICS
non-CICS
(for example,
CICS TG)
CICS
non-CICS
(for example,
CICS TG)
CICS
IMS
Function
Shipping
Yes
Yes
(See note)
No
Yes
No
Yes
No
Asynchronous
Processing
Yes
Yes
(See note)
No
Yes
No
Yes
Yes
Transaction
Routing
Yes
Yes
(See note)
Yes
Yes
No
No
No
Distributed
program link
Yes
Yes
(See note)
Yes
Yes
No
No
No
Distributed
transaction
processing
Yes
No
No
Yes
Yes
Yes
Yes
Notes:
  • IPIC supports function shipping of all file control, transient data, and temporary storage requests between CICS TS 4.2 or later regions.
  • IPIC supports asynchronous processing of EXEC CICS START, START CHANNEL, and CANCEL commands, between CICS TS 4.1, or later regions.
  • IPIC supports transaction routing of 3270 terminals between CICS TS 4.1 or later regions, where the terminal-owning region (TOR) is uniquely identified by an APPLID. Enhanced routing of transactions invoked by terminal-oriented START commands is supported between CICS TS 4.2 or later regions.
  • IPIC supports the following DPL calls:
    • Distributed program link (DPL) calls between CICS TS 3.2 or later regions.
    • Distributed program link (DPL) calls between CICS TS and TXSeries® Version 7.1 or later.