Overview of the CSL Structured Call Interface

SCI allows IMSplex members to communicate with one another. Communication between IMSplex members can occur within a single z/OS® image or among multiple z/OS images. The individual IMSplex members do not need to know where the other members reside or what communication interface to use.

SCI provides the following functions to an IMSplex:

Routes messages and requests within an IMSplex.
Registers and deregisters IMSplex members.
Notifies IMSplex members when a member joins or leaves the IMSplex.
Provides security authentication of members when they join the IMSplex.
Provides a single call interface to isolate the client and server from the underlying communications technology.

Any IMSplex member that requires SCI services must have an SCI on its z/OS image. There can be at most one SCI address space per IMSplex on each z/OS image.

Note: DBRC automatic RECON loss notification and parallel RECON access use SCI, but not RM or OM. You can bring up an SCI address space without requiring the other CSL manager address spaces for automatic RECON loss notification.

Recommendation: Initialize each CSL manager address space in an IMSplex.