DECnet-11S, Version 4.2 RSX-11S Network Software

DECnet-11S, Version 4.2, is a network software product designed to allow RSX-11S systems to operate as routing or nonrouting (end) nodes within DECnet computer networks, specifically Phase IV, with compatibility for Phase III. It supports up to 1023 nodes per network area for Phase IV and 255 for Phase III.

Key features and capabilities include:

• Communication: Provides task-to-task communication, network file operations, and homogeneous network command terminal support (CTERM, RMT), utilizing DIGITAL Network Architecture (DNA) protocols. It communicates over synchronous/asynchronous lines, Ethernet LANs, and parallel interfaces. Tasks written in MACRO-11, FORTRAN IV, and FORTRAN-77 are supported.
• Routing: Implements Adaptive Routing to forward messages between nodes and Area Routing to manage communications across different network areas (up to 63 areas). Routing nodes offer full functionality, while end nodes consume fewer resources but cannot route for other nodes.
• System Management: Supports Down-Line System Loading for initial memory images, Upline Dumping for crash analysis, and Down-Line Task Loading for programs, simplifying operation for systems without mass storage. The Network Control Program (NCP) is used for network management, including displaying statistics, controlling components, and testing network operation.
• Data Link: Employs the DIGITAL Data Communications Message Protocol (DDCMP) for error detection/correction and physical link management over point-to-point and multipoint connections, with auto-answer capability. It also supports Ethernet. Direct Line Access (DLX) allows user tasks to bypass DECnet protocols for direct control of communication lines.

System configuration depends on various factors, including CPU type, memory, line characteristics, and message traffic. The document details supported hardware configurations, including UNIBUS and QBUS devices, with "load costs" to help compute maximum system configurations based on CPU type.

Minimum hardware requirements include specific memory (18KW for end nodes, 20.5KW for routing nodes, plus 3KW for Ethernet), disk blocks, and a range of PDP-11 central processors with various communication devices.

The software requires the RSX-11S Operating System (Version 4.2) and optionally FORTRAN-77/RSX and FORTRAN IV. DIGITAL provides a 90-day warranty, installation services (including a courtesy installation with a Startup Service Package), NETstart Services for network setup, and various Software Product Service Agreements (DECsupport, BASIC, Self-Maintenance) for ongoing support, revisions, and training. Licensing is on a single-use basis per CPU, with options for distribution and documentation.