HP OpenVMS Systems Documentation

Content starts here DECnet-Plus for OpenVMS

DECnet-Plus for OpenVMS

Introduction and User's Guide

Order Number: AA--Q191F-TE

November 1996

This manual introduces DECnet-Plus for OpenVMS. It provides an overview of the product's features and a conceptual overview of DECnet-Plus.

Revision/Update Information: This manual supersedes the DECnet/OSI for OpenVMS Introduction and User's Guide.

Operating Systems: OpenVMS VAX Version 7.1
OpenVMS Alpha Version 7.1

Software Versions: DECnet-Plus for OpenVMS Version 7.1

Digital Equipment Corporation Maynard, Massachusetts

November 1996

Digital Equipment Corporation makes no representations that the use of its products in the manner described in this publication will not infringe on existing or future patent rights, nor do the descriptions contained in this publication imply the granting of licenses to make, use, or sell equipment or software in accordance with the description.

Possession, use, or copying of the software described in this publication is authorized only pursuant to a valid written license from DIGITAL or an authorized sublicensor.

DIGITAL conducts its business in a manner that conserves the environment and protects the safety and health of its employees, customers, and the community.

© Digital Equipment Corporation 1996. All rights reserved.

The following are trademarks of Digital Equipment Corporation: Bookreader, DDCMP, DEC, DECdirect, DECnet, DECNIS, DECserver, DECsystem, DECwindows, DIGITAL, DNA, InfoServer, OpenVMS, OpenVMS Cluster, PATHWORKS, ULTRIX, VAX, VAX DOCUMENT, VAXcluster, VAXstation, VMS, RSX, and the DIGITAL logo.

The following are third-party trademarks:

Macintosh is a registered trademark of Apple Computer, Inc.
MS-DOS is a registered trademark of Microsoft Corporation.
OS/2 is a registered trademark of International Business Machines Corporation.
OSF/1 is a registered trademark of Open Software Foundation, Inc.
OSI is a registered trademark of CA Management, Inc.
SCO is a trademark of Santa Cruz Operations, Inc.
UNIX is a registered trademark in the United States and other countries, licensed exclusively through X/Open Company Ltd.

All other trademarks and registered trademarks are the property of their respective holders.

This document was prepared using VAX DOCUMENT, Version V3.2m.

Contents Index


This book introduces the DECnet-Plus for OpenVMS (formerly DECnet/OSI) product, providing an overview of the product's features and a conceptual overview of DECnet-Plus software. Also described are common end-user tasks such as how to use the remote file, remote login, and mail utilities. A complete glossary of DECnet-Plus terminology is also included.

See your Software Product Description (SPD) for detailed information about new features and product requirements.

Intended Audience

This book is written for:

  • Network planners and managers, both DECnet for OpenVMS (Phase IV) users and new DECnet-Plus (Phase V) users
  • OpenVMS system managers
  • Installers of OpenVMS
  • Namespace planners and managers
  • DECdts planners and managers
  • Managers of these Open Systems Interconnection (OSI) features:
    • OSI Transport connections
    • X.25 communications
    • Wide area network device drivers (WANDD)
    • Remote OSI file operations
    • DECnet-Plus virtual terminal
    • Writing and running additional OSI applications

Document Structure

This book has four parts:

  • Part I provides an overview of:
    • Transitioning to DECnet-Plus
    • Features and components of the DECnet-Plus for OpenVMS product

  • Part II provides conceptual information about:
    • DECnet-Plus for OpenVMS
    • X.25 networking
  • Part III provides user information on:
    • Using remote files with DECnet-Plus
    • Using the DECnet-Plus login utility
    • Sending mail to DECnet-Plus nodes
  • Part IV is a glossary of DECnet-Plus terminology.

Guide to Documentation

DECnet-Plus for OpenVMS documentation is available in three sets:

  • Documentation set for OpenVMS Alpha systems
  • Documentation set for OpenVMS VAX systems
  • Supplemental X.25 documentation set for OpenVMS Alpha systems

Table 1 lists the documentation that supports this version of the DECnet-Plus for OpenVMS software.

Table 1 DECnet-Plus for OpenVMS Documentation
Document Contents
Documentation Sets: OpenVMS Alpha and VAX Systems
DECnet-Plus for OpenVMS Introduction and User's Guide This manual. Describes the manuals in the documentation sets, outlines the DECnet-Plus for OpenVMS features and tools, explains how to use and manage an end system, and provides a comprehensive glossary of DECnet terminology.
DECnet-Plus for OpenVMS Release Notes Print this text file at the beginning of the installation procedure and read it before you install DECnet-Plus for OpenVMS. Volume 1 of the DECnet-Plus for OpenVMS distribution kit contains the Release Notes.

Describes changes to the software; installation, upgrade, and compatibility information; new and existing software problems and restrictions; and software and documentation corrections.

DECnet-Plus for OpenVMS Installation and Basic Configuration Explains how to install and configure the DECnet-Plus for OpenVMS software and how to perform postinstallation tasks.
DECnet-Plus for OpenVMS Installation Quick Reference Card Provides quick-reference information to help you install DECnet-Plus software on an OpenVMS node. Use this card with the DECnet-Plus for OpenVMS Installation and Basic Configuration manual.
DECnet-Plus for OpenVMS Applications Installation and Advanced Configuration Explains how to install X.25 for OpenVMS Alpha, X.25 Access and X.25 Native Mode for OpenVMS VAX (formerly VAX P.S.I. Access and VAX P.S.I.), FTAM, VT, and OSAK software. Includes information about how to configure DECnet-Plus for OpenVMS using the Advanced configuration option and how to modify an existing configuration.
DECnet-Plus for OpenVMS Network Management Provides in-depth information about how to monitor and manage DECnet-Plus for OpenVMS systems using various tools and Network Control Language (NCL) commands. Explains how to set up and use event dispatching and how to perform all day-to-day management tasks for the local DECnet-Plus for OpenVMS node, including setting up OpenVMS clusters, managing security, downline loading, and monitoring the network.
DECnet-Plus for OpenVMS Network Management Quick Reference Guide Provides quick-reference information about the tools that help you manage and monitor a DECnet-Plus network. Use this guide with the DECnet-Plus for OpenVMS Network Management manual.
DECnet-Plus Network Control Language Reference Outlines command descriptions and examples for all Network Control Language (NCL) commands that you execute to manage, monitor, and troubleshoot the network. Begins with an orientation chapter that contains information about how to execute NCL commands, followed by a command chapter for each module in the DECnet Phase V layered model.
DECnet-Plus Planning Guide Provides configuration and planning guidelines, including namespace planning information, to help you transition a network from the DECnet Phase IV to DECnet Phase V architecture.
DECnet-Plus Problem Solving Explains how to isolate and solve DECnet problems in an OpenVMS environment that can occur while the network is in operation. Includes information about how to perform loopback tests and how to use the DTS/DTR utility to solve problems.
DECnet-Plus DECdns Management Explains DECdns concepts and how to manage a DECdns distributed namespace. Use this manual with the DECnet-Plus Planning Guide.
DECnet-Plus DECdts Management Introduces DIGITAL Distributed Time Service (DECdts) concepts and describes how to manage the software and system clocks.
DECnet-Plus DECdts Programming Contains DECdts time routine reference information and describes the time-provider interface (TPI).
DECnet-Plus OSAK Programming Explains how to use the OSAK (OSI Applications Kernel) interface to create OSI (Open Systems Interconnection) applications for any supported operating system.
DECnet-Plus OSAK Programming Reference Provides reference information on using the OSAK interface to create OSI applications on any supported operating system.
DECnet-Plus OSAK SPI Programming Reference Provides reference information about using the OSAK session programming interface (SPI) to create OSI applications on any supported operating system.
DECnet-Plus FTAM and Virtual Terminal Use and Management Explains how to use and manage FTAM (File Transfer, Access, and Management) software for remote file transfer and management and VT (Virtual Terminal) for remote login to OSI-compliant systems.
DECnet-Plus FTAM Programming Explains how to access the FTAM protocol through DIGITAL's FTAM API (application programming interface).
DECnet-Plus for OpenVMS Programming A three-part manual. Contains information about how to design and write an application that follows a client/server model and uses the OpenVMS Interprocess Communication ($IPC) system service and the transparent and nontransparent communication with the queue Input/Output ($QIO) system service. Explains how to write programs using the OpenVMS system services to communicate with OSI transport services. Provides information about the Common Management Information Service (CMISE) API.
DECnet/OSI for VMS CTF Use Explains how use the Common Trace Facility (CTF) troubleshooting tool to collect and analyze protocol data from networking software.
DECnet/OSI for VMS X.25 Management

DECnet/OSI for VMS VAX X.25 Problem Solving

DECnet/OSI for VMS VAX P.S.I. Programming

DECnet/OSI for VMS VAX P.S.I. Programming Reference

DECnet/OSI for VMS VAX WANDD Programming

DECnet/OSI for VMS VAX P.S.I. Accounting

DECnet/OSI for VMS VAX P.S.I. X.25 Use

DECnet/OSI for VMS VAX P.S.I. X.29 Management

DECnet/OSI for VMS VAX X.25 Security

For OpenVMS VAX systems only. Provides X.25 and X.29 information for X.25 Access and X.25 Native Mode (formerly VAX P.S.I. Access and VAX P.S.I.). Provides information about wide area network device driver (WANDD) software.
X.25 for OpenVMS Management Guide For OpenVMS Alpha systems only. Explains how to manage and monitor an X.25 system using network tools.
X.25 for OpenVMS Security Guide For OpenVMS Alpha systems only. Explains the X.25 security model and the tasks required to set up and manage X25 security.
X.25 for OpenVMS Problem Solving For OpenVMS Alpha systems only. Provides guidance on how to solve problems that can occur while using an X.25 system.
Supplemental X.25 Documentation Set (OpenVMS Alpha Systems)
X.25 for OpenVMS Accounting Explains how to use X.25 accounting to obtain performance records and information about how X.25 is being used.
X.25 for OpenVMS Configuration Discusses how to configure X.25 on an OpenVMS Alpha system.
X.25 for OpenVMS Programming Explains how to write X.25 and X.29 programs to perform network operations.
X.25 for OpenVMS Programming Reference Provides reference information for X.25 and X.29 programmers.
X.25 for OpenVMS Utilities Explains how to use and manage X.25 Mail and X.29 communications.

For additional information on the DECnet-Plus products and services, access the DIGITAL OpenVMS World Wide Web site. Use the following URL:


Reader's Comments

DIGITAL welcomes your comments on this manual or any of the DECnet-Plus documents. Send us your comments through any of the following channels:

Internet openvmsdoc@zko.mts.dec.com
Fax 603 881-0120, Attention: OSSG Documentation, ZKO3-4/U08
Mail OSSG Documentation Group, ZKO3-4/U08
110 Spit Brook Rd.
Nashua, NH 03062-2698

How To Order Additional Documentation

Use the following table to order additional documentation or information. If you need help deciding which documentation best meets your needs, call (800-282-6672).


The following terms are used interchangeably:

  • Transition and migration
  • Phase IV and DECnet Phase IV
  • Phase V and DECnet Phase V
  • System and node
  • End system and end node
  • Intermediate system and router
  • Multivendor and non-DIGITAL-specific
  • Link state and:
    • Link state routing algorithm
    • Link state protocol
    • DECnet-Plus routing algorithm
    • DECnet-Plus routing
  • Name service and directory service


The following conventions apply to this book.

Convention Meaning
special type Indicates a literal example of system output or user input. In text, indicates command names, keywords, node names, file names, directories, utilities, and tools. On a DECnet-Plus for ULTRIX system, enter the word or phrase in the exact case shown.

You can abbreviate command keywords to the smallest number of characters that OpenVMS, DEC OSF/1, NCL, DECdns, DECdts, and the other utilities accept, usually three characters.

italic Indicates a variable.
text style Indicates a new term defined either in the text or in the glossary.
[Return] Indicates that you press the return key.
[Ctrl/] x Indicates that you press the control key while you press the key noted by x.
[ ] In command format descriptions, indicates optional elements. You can enter as many as you want.
{ } In command format descriptions, indicates you must enter at least one listed element.

Part I
DECnet-Plus for OpenVMS Overview

Part I provides an overview of the transition from DECnet Phase IV to DECnet-Plus (Phase V). It also includes an overview of what is included with the DECnet-Plus for OpenVMS base system. This section includes the following chapters:

  • Chapter 1 --- Introducing DECnet-Plus for OpenVMS
  • Chapter 2 --- DECnet-Plus for OpenVMS Components

Chapter 1
Introducing DECnet-Plus for OpenVMS

DIGITAL's DECnet-Plus network is a family of hardware and software products that allows DIGITAL operating systems to communicate with each other and with systems produced by other vendors.

The DECnet-Plus network supports remote system communication, resource sharing, and distributed processing. Network users can access resources on any system in the network as well as the resources of other vendors' systems on multivendor networks.

DECnet-Plus networking software provides true network independence. You get the full functionality of DECnet Phase IV, as well as DECnet enhancements plus full TCP/IP compatibility and OSI functionality.

DECnet-Plus for OpenVMS is DIGITAL's OpenVMS implementation of:

  • The Open Systems Interconnection (OSI) communications specifications, as defined by the International Organization for Standardization (ISO).
  • DIGITAL's communications architecture, DIGITAL Network Architecture (DNA) Phase V, which is also backward compatible with the Phase IV architecture.

Phase V integrates the DNA and OSI layers. The DNA Phase V reference model is the architectural model on which DECnet-Plus networking implementations are based. DECnet-Plus also includes support for the internet standards RFC 1006 and RFC 1859, which allow you to run OSI and DECnet Phase IV applications over TCP/IP.

Table 1-1 shows the changes that have evolved with each new phase.

Table 1-1 DNA Phases
Phase I Limited to two nodes
Phase II Up to 32 nodes: file transfer, remote file access, task-to-task programming interfaces, network management
Phase III Up to 255 nodes: adaptive routing, downline loading, record access
Phase IV Up to 64,449 nodes: Ethernet local area networks, area routing, host services, OpenVMS Cluster support
Phase V Virtually unlimited number of systems: OSI protocol support, transparent transport level links to TCP/IP, multivendor networking, local or distributed name service, distributed network management

DECnet-Plus for OpenVMS integrates DECnet and OSI network protocols which provides continued support for DECnet applications and enables support for OSI applications on OpenVMS. With separate TCP/IP software running on the same system, DECnet-Plus supports a multivendor, multiprotocol network environment. DECnet applications can be run over NSP, CLNP, or TCP/IP transports. OSI applications can be run over CLNP or TCP/IP transports.

A full implementation of the DIGITAL Network Architecture (DNA) Phase V for OpenVMS systems, the OSI component of the DECnet-Plus software, is implemented in accordance with the current U.S. and UK GOSIP requirements. GOSIP is the Government OSI Profile that defines OSI capabilities required by government procurement.


Chapter 3 contains more conceptual information on the OSI Reference Model, OSI terminology (protocols, stacks, dialogues, entities, services), and how each specific layer relates to DECnet-Plus for OpenVMS.

1.1 Preparing for a Migration to DECnet-Plus

A number of automated tools (DECnet migration utilities and the NCP Emulator) and simplified configuration procedures are available to help you migrate to DECnet-Plus.

The complexity of the transition from Phase IV to Phase V architecture varies depending on the complexity of your existing network. In general, the smaller the network, the easier the transition. For larger networks, more planning is required. Nevertheless, whether your network is large or small, you can accomplish the transition without disrupting day-to-day operations.

DECnet-Plus now supports the fast configuration option, which a system or network manager can use to configure DECnet-Plus quickly on an OpenVMS system by invoking the net$configure.com procedure.

With the Fast Configuration option, you can configure a Phase IV system for network connectivity by answering a few questions. This feature is useful when you upgrade a DECnet Phase IV node to a DECnet-Plus node at some time in the future.

For information about how to configure your network using the Fast Configuration option, see the DECnet-Plus for OpenVMS Installation and Basic Configuration manual.

1.1.1 Differences Between DECnet Phase IV and DECnet-Plus Phase V

DECnet-Plus is the implementation of the fifth phase of the DIGITAL Network Architecture (DNA). Phase V integrates the Open System Interconnection (OSI) protocols with DECnet protocols. In addition, Phase V includes support for the Internet standard RFC 1006 and the Internet draft RFC 1859, allowing OSI and DECnet applications to run over TCP/IP. Thus, applications that use DECnet-Plus can communicate with peer OSI and DECnet applications on any DECnet Phase IV-based system or OSI-based system, whether from DIGITAL or from other vendors.

The addition of the OSI protocols and the TCP/IP communications capability is, therefore, the primary difference between DECnet Phase IV and DECnet-Plus Phase V. There are, however, other differences. DECnet-Plus contains many features designed to enhance networking capabilities. These new features include:

  • Global naming/directory services --- In large networks, the number of nodes and users makes it difficult to manage any form of local directory service. Global (or distributed) name services allow large networks to easily store, manage, and access addressing information for (potentially) millions of network objects, such as end systems, users, printers, files, and disks. With the explosion of PCs as the desktop device of choice, networks containing millions of nodes have become a reality.
  • Optional local naming/directory services --- Smaller networks do not have as critical a need for global directory services.
  • Expanded network management capabilities via the Network Control Language (NCL) --- As networks become more complex, the management of networks has also become more complex. NCL enables network managers to access a wide range of manageable entities in the network for a wide range of management tasks.
  • An improved routing algorithm (link state routing) --- The larger a network becomes, the more overhead is generated by passing routing information between routers and between routers and end systems. Link state routing provides a more efficient algorithm for passing routing information while keeping the overhead traffic to a minimum. Link state routing is supported only on dedicated routers.
  • Host-based routing --- You can configure your network to enable host-based routing using the routing vector protocol. Host-based routing allows an OpenVMS system to operate as a DECnet-Plus intermediate system (IS). This feature is useful for those configurations where you need to route from a local area network (LAN) to a wide area network (WAN) and want to use an existing system to do the routing rather than investing in a dedicated router.
  • Increased addressing --- Networks can now grow to include potentially millions of nodes. DECnet-Plus uses the OSI standard address format. This format is designed to allow each node in a universal network to have a unique address. In other words, networks can now grow well beyond the bounds of any other addressing format currently in use. Existing Phase IV addresses can continue to be used for upgraded systems. The Phase IV address is moved into the OSI address format.
  • Address autoconfiguration --- DECnet-Plus nodes can take advantage of the address autoconfiguration feature where the adjacent router configures the node address for you.
  • Single installation/configuration for OSI components --- X.25, the Wide Area Device Drivers (WANDD), FTAM and Virtual Terminal (VT) applications are included in the DECnet-Plus H-Kit.

To fully benefit from these enhancements, you may need to make changes to your network. Prior to upgrading from DECnet Phase IV to DECnet-Plus, you must make certain decisions:

  • Network addressing --- Will users on the DECnet-Plus network have the ability to communicate with users on other OSI networks, either through electronic mail, EDI, FTAM, VTP, or other internetwork utilities? If yes, you must obtain a unique network identifier (IDP) from an authorized authority such as ANSI. If not, a default IDP is provided with DECnet-Plus that you can use at installation/configuration time.
  • Name services --- Will name services be provided locally to each node or distributed throughout the network? Larger networks can benefit greatly from a distributed name service. The local service option is similar to Phase IV.
  • DNA Phase V architecture has an overall management architecture called the Enterprise Management Architecture (EMA). EMA defines a framework for the management of heterogeneous, multivendor distributed computing environments and the communications facilities that link them. EMA covers the entire distributed system, not just the communications aspects. The enterprise network comprises communication networks, computing systems, databases, and applications.
    In conformance with EMA, DECnet-Plus provides distributed network management facilities that allow you to manage the network both in a local and distributed manner. The network management design is based on the director-entity framework and models defined by EMA. For an introduction to DECnet-Plus network management, see Section 3.10.
  • The DECnet-Plus network management protocol is based on DNA Common Management Information Protocol (DNA CMIP) draft standard for network management operations. CMIP is used for encoding network management operations that can be performed on an entity. CMIP permits the exchange of information between a director and an agent. CMIP supersedes the Phase IV Network Information and Control Exchange (NICE) protocol.
    DECnet-Plus for OpenVMS provides a callable interface for management operations. This interface, the CMIP Management Listener (CML), consists of CML$ run-time routines. CML$ routines perform the encoding of management data into CMIP and the decoding of data from CMIP, as well as interfacing to the entities.
    DECnet Phase IV applications that have been written to create logical links to the Phase IV Network Management Listener (NML) and then parse the returned NICE protocol messages are not supported for managing DECnet-Plus for OpenVMS systems. To run on a network composed of DECnet-Plus systems, those applications must be rewritten to use DECnet-Plus network management software and protocols, such as CML and CMIP.

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