IMS provides address spaces to execute system and application programs that use IMS services.
These address spaces are called dependent regions. You could think of these as layers in a container.
These regions can be either message driven, that is,applications that process messages that come into IMS TM as input, or batch regions
IMS dependent regions support persistent JVMs to provide the capability to efficiently make calls that interoperate between Java and languages such as COBOL and PL-one. This enables the capability to leverage existing IMS applications as well as extend functionality using Java