The IMS Database Manager provides a central point for the control and access to application data. IMS provides a full set of utility programs to provide all these functions within the IMS product. This section describes the various types of z/OS address spaces and their relationships with each other. The core of an IMS subsystem is the control region , running in one z/OS address space. This has a number of dependent address spaces running in other regions that provide additional services to the control region, or in which the IMS application programs run.
In addition to the control region, some applications and utilities used with IMS run in separate batch address spaces. These are separate from an IMS subsystem and its control region, and have no connection with it.
For historical reasons, some documents describing IMS use the term region to describe a z/OS address space, for example, IMS Control Region. In this course we use the term region wherever this is in common usage. You can take the term region as being the same as a z/OS address space.
Structure of the IMS DB/DC subsystem illustrates the IMS DB/DC subsystem. If you want more details, we refer you to An Introduction to IMS (ISBN 0-13-185671-5) .
