Print Services Access Facility

The architecture of Print Services Access Facility (PSAF) on z/OS is centered around several key components that work together to provide robust printing capabilities, particularly for IBM 3800 and 3820 printers. The core components include the Print Services Facility (PSF), the Print Management System (PMS), and the Output Manager. The PSF is responsible for processing the print data stream, interpreting commands, and formatting the output for the target printer.

The PMS manages print queues, job scheduling, and print job management tasks. The Output Manager controls the final output process, including the physical printing of the documents. Communication between these components occurs primarily through z/OS internal mechanisms, such as cross-memory services and system services.

PSAF utilizes z/OS datasets for storing configuration data, print jobs, and other related information. Network communication, when required for printer connectivity, typically relies on TCP/IP and SNA/APPC protocols. PSAF does not expose REST or SOAP APIs.

Instead, interaction with PSAF is achieved through native z/OS commands, system interfaces, and configuration files. For example, printer configuration is managed through PSF configuration files, and print jobs are controlled using commands like `START` and `STOP`. PSAF integrates with z/OS security, supporting authentication through RACF and other z/OS security features.

This integration ensures that access to printing resources is controlled and that print jobs are secured. The ability to dynamically create page definitions (PAGEDEFs) and form definitions (FORMDEFs) is a key architectural feature, allowing for highly customized print output. Monitoring and logging are handled through z/OS system tools and PSAF-specific logs, providing detailed information on print job status, errors, and system performance.

PSAF's architecture is designed to handle high-volume printing environments, providing scalability and reliability for enterprise printing needs.