DECnet-VAX Internals

This document is a student workbook for a course on DECnet-VAX Internals. It covers various aspects of DECnet-VAX, including:

• VMS I/O Concepts: A review of Virtual Memory, OIO processing, and Device Driver Data Structures.
• Digital Network Architecture (DNA): An overview of DECnet layers and protocols, Ethernet data link and physical link layers, DDCMP, X.25, and Computer Interconnect (CI).
• DECnet-VAX Software Components: A discussion of data link device drivers, NETDRIVER, NETACP, RTTDRIVER, REMACP, RTPAD, special processes, objects, NDDRIVER, and other DECnet components.
• DECnet-VAX Data Structures: An examination of VMS data structures used by DECnet, specific DECnet data structures, and how to use the System Dump Analyzer (SDA) to analyze them.
• Major Network Mechanisms: An exploration of logical link creation, NSP flow control, sending and receiving data, routing table updates, and other network mechanisms.
• Tracing DECnet Actions: Hints for reading source listings, major DECnet-VAX modules, tracing logical link creation, sending normal data, and other DECnet actions.
• Network Design and Performance Considerations: Discussions on buffers, DECnet transfer process, NETACP, routing parameters, timers, VMS nonpaged pool parameters, and other performance considerations.
• Protocol Lab Exercises: Practical exercises to interpret protocol messages and analyze DECnet behavior.

The workbook aims to provide a comprehensive understanding of the protocols, components, data structures, and algorithms used in implementing DECnet-VAX.