Within an enterprise server, COBOL applications run in response to service requests issued by several different client types.
A COBOL program that implements a service is a program that reads in a parameter block, processes it and returns a results block. The interface to the service is exposed by means of a service definition. Not all COBOL applications are suitable for exposing as services. For advice, see the chapterPreparing Applications for Enterprise Server in the Interface Mapping Toolkit book.
Enterprise servers provide session and state management for COBOL applications, as well as optionally interfacing with external resource managers to coordinate resource updates.
An enterprise server provides a pool of pre-initialized service execution processes, within which COBOL applications are executed. As the COBOL applications run within their own address spaces, they are isolated from other programs executed within the enterprise server. Multiple execution processes enable concurrent processing of COBOL programs responding to client request messages.
When you install Enterprise Server, one enterprise server is automatically set up for you. You can create further enterprise servers as required.