OpenVMS Software Overview

The "OpenVMS Software Overview," published in December 1995, describes the extensive capabilities and computing environments of the OpenVMS operating system, supporting both VAX (32-bit) and Alpha (32/64-bit) processors.

The document is organized into three main parts:

1. OpenVMS Computing: This section introduces OpenVMS's flexible, general-purpose, and multiuser nature, outlining its support for various computing styles (timesharing, real-time, transaction processing) and configurations (standalone, VMScluster, and networked systems). It emphasizes OpenVMS's commitment to open system standards (POSIX, X/Open, OSF, ISO) to ensure application and user portability and multivendor interoperability. Key capabilities include distributed processing (client/server models, middleware, and Distributed Computing Environment (DCE) services), high-integrity production systems (dependability, availability tools like VMSclusters and volume shadowing, data integrity with RMS Journaling and DECdtm, and transaction processing via ACMS), as well as comprehensive system and network management tools.
2. OpenVMS Systems Software: This part provides a technical overview of the base OpenVMS operating system components, including its kernel (memory, process/time, and I/O subsystems), core services (DCL, Run-Time Library, Record Management Services, and optional POSIX), and various utility programs. It details the programming software for application development, such as compilers, debuggers, and POSIX programming interfaces. Additionally, it describes the diverse user interfaces (DCL command line, DECwindows Motif graphical interface, POSIX shell, and forms-based environments like ALL-IN-1), along with features for information handling, text processing, and electronic mail.
3. Open Distributed Computing Environments: This section focuses on OpenVMS's integration into heterogeneous networks, covering networking software like DECnet/OSI and TCP/IP for multivendor environments. It explains how middleware services and DCE enable multivendor interoperability and client/server applications. OpenVMS is also presented as a powerful server for PC and Macintosh clients (using PATHWORKS), providing file, print, mail, database, and transaction processing services. The document concludes by detailing OpenVMS's support for commercial production systems, ensuring high availability, data integrity, and manageability through tools such as StorageWorks RAID, POLYCENTER products, and the Business Recovery Server for disaster tolerance.

In summary, OpenVMS is portrayed as a robust, scalable, and adaptable operating system designed for diverse computing needs, from individual workstations to complex, distributed, multivendor enterprise environments, with a strong focus on reliability, security, and adherence to industry standards.