VTAM/Switch

The architecture of VTAM/Switch is designed to efficiently manage multiple VTAM application connections through a single 3270 session. The core components include the Session Manager, Application Router, Configuration Manager, and Security Module. The Session Manager handles the establishment and termination of 3270 sessions.

The Application Router directs traffic to the appropriate VTAM applications based on predefined routing rules. The Configuration Manager uses JCL and configuration datasets to define application connections, security policies, and session parameters. The Security Module integrates with the underlying z/OS and zVSE/VSEn security infrastructure, typically RACF, to enforce authentication and access control.

Communication between components occurs through internal system interfaces and the SNA protocol. The Application Router uses routing tables defined in the configuration datasets to determine the destination application for each session. The system utilizes the underlying platform's storage mechanisms for configuration data and logging.

The network requirements include connectivity to the VTAM network and the applications being accessed. The system supports audit logging for all session activities, including connection attempts, application switches, and security events. For example, the Application Router uses routing rules to direct traffic based on LU names.