Software Product Description

This document describes DECnet-ULTRIX, Version 4.0, a software product for RISC and VAX ULTRIX systems, specifically implemented as an end-node only within Digital Network Architecture (DNA) Phase IV.

Key Features and Capabilities:

1. Dual Protocol Support: Enables communication between Digital systems using DNA Phase III/IV protocols and non-Digital systems using Internet (TCP/IP-based) protocols simultaneously. It allows DECnet and TCP/IP to coexist and share system resources.
2. Core Network Services: Offers essential network capabilities including:
   • Task-to-Task Communications: Allows programs on different nodes to exchange data.
   • Network Virtual Terminal (CTERM): Provides heterogeneous remote terminal support, allowing users to establish logical connections to various DECnet nodes as if physically connected.
   • Remote File Transfer (DCP): Utility for transferring files between DECnet-ULTRIX and other Phase III/IV nodes.
   • Network File Access: Allows remote Digital systems to perform directory operations and file manipulations (read, write, create, delete, print) on a DECnet-ULTRIX system.
   • Mail: Extends the ULTRIX mail system to send and receive mail across DECnet Phase III/IV systems.
3. DECnet-Internet Gateway: A bi-directional gateway allowing DECnet and Internet users to communicate via file transfer (FTP/DAP), remote login (TELNET/CTERM), and mail (SMTP/MAIL-11). It does not require special software or accounts on client systems.
4. Network Management (NCP): Provides tools to display network statistics and error information, control network components, and test network operations locally or remotely. It also supports network event logging.
5. End-Node Functionality:
   • Communicates directly with other Phase IV nodes on Ethernet or with Phase III/IV nodes via a routing node.
   • Supports incoming connections from all Phase III systems, with limited outgoing support to specific Phase III systems (DECnet-VAX, DECnet-RT).
   • Cannot route messages on behalf of other nodes, resulting in lower overhead compared to routing nodes.
   • Supports downline loading for various DECserver, DECrouter, Internet Portal, and X25router products.
   • Does not support communication with Phase II nodes.
6. Compatibility & Protocols:
   • Supports Ethernet Version 2.0 and synchronous DDCMP protocols for data link and physical layers (RISC versions only support Ethernet).
   • Includes 802.3 compatibility.
7. System Requirements: Runs on VAX, MicroVAX, VAXstation, and Digital RISC systems, requiring ULTRIX Operating System V4.0 or ULTRIX Worksystem Software V4.0. It has specific disk space requirements (e.g., ~2.42MB for VAX, ~3.72MB for RISC).

The product supports large networks (up to 1023 nodes per area, 63 areas per network) and its functions in mixed networks may vary based on other DECnet products involved.