Tivoli Netview Access Services

The architecture of Tivoli Netview Access Services (TNAS) is centered around providing a 3270 session management solution for z/OS. The main components include the TNAS server, the session manager, and the VTAM interface. The TNAS server is the core component, responsible for user authentication, session management, and overall control of the TNAS environment.

It interacts with the z/OS security system, such as RACF, to authenticate users and enforce access control policies. The session manager is responsible for handling individual VTAM application sessions. It allows users to start, switch between, and end sessions using specific commands or hotkeys.

The VTAM interface facilitates communication with z/OS applications using the VTAM protocol. This interface handles the establishment and management of sessions between the TNAS server and the VTAM applications. Configuration is primarily managed through configuration files, which define session parameters, security settings, and VTAM resource definitions.

Monitoring is achieved through z/OS system monitoring tools. TNAS is not supported; therefore, any architectural considerations should focus on migrating to a supported terminal emulation solution, such as IBM CL/Supersession, which provides a similar architecture with modern features and support.