Screen Definition Facility II

The architecture of Screen Definition Facility II (SDF II) is centered around the ISPF interface, map definition files, and the map generation process. The ISPF interface provides the primary means for users to interact with the product, offering a user-friendly environment for designing and managing 3270 screen layouts. Map definition files, typically stored in partitioned data sets (PDS) or VSAM files, serve as the repository for screen definitions, including field attributes, layout specifications, and other relevant information.

The map generation process is a critical component, translating the screen definitions into physical maps that can be used by CICS and IMS applications. The main components include the ISPF editor, the map definition file storage, and the map generation utilities. Communication between these components is facilitated through the ISPF environment and the underlying operating system services.

SDF II does not use a dedicated database; instead, it relies on the file system for storing map definitions. Network requirements are minimal, as the product primarily operates within the z/OS, z/VM, or zVSE/VSEn environments. Security is managed through the underlying CICS or IMS security mechanisms, which may include role-based access control (RBAC).