HP OpenVMS Systems Documentation

Content starts here DECnet-Plus


Planning Guide

Order Number: AA-QBTHE-TE

November 1996

This manual provides an overview of the transition and planning tasks necessary to move from DECnet for OpenVMS (Phase IV) to DECnet-Plus for OpenVMS (Phase V) and DECnet-Plus for DIGITAL UNIX.

Revision/Update Information: This manual supersedes the DECnet/OSI Planning Guide.

Operating Systems: OpenVMS VAX Version 7.1
OpenVMS Alpha Version 7.1
DIGITAL UNIX Version 4.0

Software Versions: DECnet-Plus for OpenVMS Version 7.1
DECnet/OSI for DIGITAL UNIX Version 4.0

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, VMScluster, and the DIGITAL logo.

The following are third-party trademarks:

Macintosh is a registered trademark of Apple Computer, Inc.
Microsoft, MS, and MS--DOS are registered trademarks of Microsoft Corporation.
MS-DOS is a registered trademark of Microsoft Corporation.
Motif, OSF, OSF/1, OSF/Motif, and Open Software Foundation are registered trademarks of the Open Software Foundation, Inc.
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.
TCPware is a registered trademark of Process Software Corporation.
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 provides an overview of the transition and planning tasks necessary to move from DECnet for OpenVMS (Phase IV) to DECnet-Plus for OpenVMS (Phase V) and DECnet-Plus for DIGITAL UNIX. It describes how to:

  • Use global network addresses
  • Obtain a unique initial domain part (IDP) for your DECnet Phase V network
  • Set up your namespace and enter node names and addresses into it
  • Use name service access features
  • Set up DECdts clerk nodes using DECdts software

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

Document Structure

This book has ten chapters:

  • Chapter 1---Preplanning: Understanding the Transition Process
    Describes the transition concepts.

  • Chapter 2---Planning the Transition
    Helps you plan for an orderly, efficient transition from a Phase IV network to a DECnet Phase V network.
  • Chapter 3---Performing Transition Tasks: An Overview
    Discusses your immediate transition tasks and the tools you need to perform them.
  • Chapter 4---Creating NSAP addresses
    Discusses the format of NSAP addresses for DECnet-Plus systems and describes how to get unique identification for your DECnet Phase V network.
  • Chapter 5---DECdns, Local namespace, and DECdts Concepts
    Describes DECdns, Local Namespace, and DECdts concepts.
  • Chapter 6---Naming Guidelines
    Provides general guidelines for all DECnet-Plus names and specific guidelines for naming clearinghouses and namespaces.
  • Chapter 7---Basic DECdns Namespace Planning for DECnet-Plus
    Contains basic DECdns planning guidelines if you choose to plan and implement a DECdns distributed namespace.
  • Chapter 8---Advanced DECdns Namespace Planning
    Provides additional guidelines to plan your distributed namespace.
  • Chapter 9---DECdns Namespace Design Example
    Shows an example of a DECdns Namespace design.
  • Chapter 10---Preparing for DECdts
    Describes how to plan your DECdts implementation, including personnel selection for the planning process, and planning for DECdts on a LAN, an extended LAN, or a WAN.

Related Documents

For a complete list of companion documents, see the DECnet-Plus for OpenVMS Introduction and User's Guide or DECnet-Plus for DIGITAL UNIX Introduction and User's Guide.

For additional information about 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


These 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 Phase V routing algorithm, or DECnet Phase V routing
  • Name service and directory service

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 conventions apply to this book.


The following conventions are for multiplatform documentation.

Indicates information specific to DECnet-Plus for OpenVMS.

Indicates information specific to DECnet-Plus for DIGITAL UNIX.
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 OpenVMS, DIGITAL UNIX, or ULTRIX tm system, enter the word or phrase in the exact case shown.

You can abbreviate command keywords to the smallest number of characters that OpenVMS, DIGITAL UNIX, 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 DECnet-Plus Introduction and User's Guide 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.
<> Indicates the end of platform-specific information.

Chapter 1
Preplanning: Understanding the Transition Process

Chapters 1 through 4 of this book describe the considerations that will help you determine how best to transition your network. The following sections define what the transition is, explain why you would want to transition your systems from the DECnet Phase IV to DECnet Phase V architecture, and help you plan how long this transition might take.

1.1 Transition Defined

Transition is the process of migrating a network from DECnet Phase IV to DECnet-Plus (Phase V) by changing:

  • Node-name-to-address mapping from the use of a Phase IV local permanent node databases to a DECdns distributed namespace, DNS/BIND, or to a Local namespace
  • Network management from the use of NCP to NCL

Transition is a multistep process. Some tasks you perform immediately as part of the DECnet-Plus installation/configuration procedure. Others you do immediately afterwards, still others perhaps later, as your network's needs change. In addition, some steps target the transition of one system, while other steps are part of the network's overall transition to DECnet-Plus.

Transition begins with the installation of the DECnet-Plus software onto the first node in the network. With this installation/configuration, the system becomes a DECnet-Plus system. Your network operates in a transition environment from the transition of the first node until all DECnet nodes migrate to DECnet-Plus.

The steps of transition are:

  1. Developing a transition plan for your network.
  2. Installing the DECnet-Plus software onto the first node.
  3. Configuring node-name-to-address mapping in at least one of the following ways:
    • Using the Local namespace.
    • Configuring the node as a DECdns clerk in an existing distributed namespace.
    • For an OpenVMS VAX or DIGITAL UNIX system, configuring the node as a DECdns server and creating a new distributed namespace. (DECdns server software is not available for OpenVMS Alpha systems.)
    • Using DNS/BIND.

  4. Performing the remaining transition-related network management tasks.
  5. Migrating to DECnet-Plus all the nodes you planned to migrate.

1.1.1 Why Make the Transition to DECnet-Plus?

DECnet Phase IV supports DECnet applications only. It does not support OSI (Open Systems Interconnection) and TCP/IP applications, which must use separate protocol stacks that DECnet Phase IV does not provide.

With DECnet Phase V (formerly known as DECnet/OSI and now, with Version 7.1, DECnet-Plus), your DECnet applications can communicate (without change) with peer OSI and DECnet applications on any system running DECnet Phase IV, Phase V, or OSI software. That system can be a DIGITAL system or one from another vendor. DECnet-Plus integrates the OSI protocol stack with the DECnet protocol stack and includes the ability to run DECnet and/or OSI applications over TCP/IP.

A growing number of emerging network applications are designed to be transported over the Open Systems Interconnection. DECnet-Plus provides a collection of standard OSI applications such as File Transfer, Access, and Management (FTAM) and Virtual Terminal (VT), plus a complete library of OSI transport protocols.

With DECnet-Plus, you can use one or more of the following name services to translate network names to node numbers and back, depending on the transport used (DECnet, OSI, or TCP/IP):

  • Local namespace (similar to DECnet Phase IV's NETNODE_REMOTE.DAT node database)
  • DECdns (DIGITAL's Distributed Naming Service)
  • DNS/BIND name resolution protocol (for TCP/IP)

When a user provides a node name to a DECnet or OSI application, the application translates it using the appropriate name service.

TCP/IP support is crucial for the many customers who need access to the TCP/IP-based Internet and to the growing number of low-cost, IP-compatible routers and carrier services. DECnet-Plus, in combination with a DIGITAL or third-party TCP/IP protocol stack for OpenVMS and DIGITAL UNIX, allows a DECnet customer to convert to TCP/IP network protocols without having to give up existing DECnet or OSI applications.

The DECnet over TCP/IP (DOTI) feature (RFC 1859), included with DECnet-Plus, allows DECnet applications to communicate over TCP/IP. The OSI over TCP/IP support (RFC 1006), included with DECnet-Plus, allows OSI applications to communicate over TCP/IP.

For new OpenVMS and DIGITAL UNIX systems, DIGITAL now bundles run-time licenses for DECnet-Plus and TCP/IP services. If you are an existing DECnet support customer, you receive DECnet-Plus automatically but need to purchase a license to use DIGITAL's TCP/IP Services for OpenVMS.

If you want to migrate your system to TCP/IP, you must install and configure the TCP/IP stack as part of your transition. Both DECnet-Plus and TCP/IP transports can be up and running concurrently and you can make the transition to TCP/IP gradually. You do not need to choose between OSI or TCP/IP. You can even choose to run your DECnet-Plus node with DECnet Phase IV functionality only and begin to use the OSI and/or TCP/IP features as you become more familiar with them.

1.1.2 How Long Does Transition Take?

The time it takes to make a complete network transition depends on your strategy. DECnet-Plus software gives you the flexibility to decide how and when to make the transition from Phase IV to DECnet-Plus. No definite time period is prescribed for all networks.

You can choose to make the transition gradually, perhaps installing DECnet-Plus software in a single area first to see how it operates and how to take advantage of its features. Or, you can install DECnet-Plus software on end systems in several areas. For example, you may chose to operate with a mixture of Phase IV and DECnet-Plus software within each area. At some point, you might decide to use the link state routing algorithm and take advantage of OSI addressing that is beyond Phase IV limitations, that is, extended addressing.


The time you spend planning the transition is an essential part of your total transition timeframe.

The time it takes to migrate one system from DECnet Phase IV to DECnet-Plus is the time it takes to perform the installation and configuration procedures on this system. However, if this is the first DECnet-Plus node on the network, you must spend some additional time on other transition tasks, such as populating the namespace, if you are creating a DECdns namespace, and converting some Phase IV databases.

1.1.3 What Is the Transition Environment?

During transition, some or all of your network operates in a mixed environment of Phase IV and DECnet-Plus nodes, either spread throughout the network or grouped into all-Phase-IV or all-DECnet-Phase-V areas.

In this transition environment, you have a mixture of Phase IV and DECnet Phase V features, including addressing, routing, and network management.

1.1.4 When Do DECnet-Plus Features Become Available?

Most features offered by the DECnet-Plus for OpenVMS and DECnet-Plus for DIGITAL UNIX products become available upon installation and configuration of the product software. However, RFC 1006, RFC 1859, and DNS/BIND require the installation of additional TCP/IP software. DECnet-Plus features include:

  • OSI applications over TCP/IP (the RFC 1006 feature)
  • DECnet applications over TCP/IP (the RFC 1859 feature)
  • DECdns for node-name-to-address mapping using a distributed namespace
  • Local namespace for node-name-to-address mapping using a local database
  • DNS/BIND as a naming service with DECnet-Plus RFC 1006 or RFC 1859 features
  • New network management structure and interfaces
  • Multicircuit end-system capability
  • OSI addressing (addressing beyond Phase IV limitations)
  • Multihoming
  • End-system autoconfiguration
    In an all-end-system LAN, these systems autoconfigure their addresses using the default local area address of 49::00-40.
    However, you can override this feature with network management commands and with the decnet_register management support tool.
  • For DECnet-Plus for OpenVMS, additional features such as OSI remote file operations (FTAM).

1.1.5 When Does Transition End?

Transition from Phase IV to DECnet-Plus ends when all:

  • Systems in the network run DECnet-Plus software
  • Routers operate with the DECnet Phase V link state routing algorithm

Because DECnet-Plus features allow for flexible transition, the network can operate with a mixture of Phase IV and DECnet-Plus systems for as long as your network requires. Therefore, as network manager, you decide how long the network continues to operate in a transition environment.

1.2 Transition Features

DECnet-Plus software provides the following features to help you during transition:

  • Coexistence of Phase IV and DECnet-Plus: backward compatibility
    DECnet-Plus software is compatible with DECnet Phase IV software; DECnet-Plus systems can coexist with and fully interoperate with Phase IV nodes. In addition to supporting OSI protocols, DECnet-Plus systems continue to support all Phase IV protocols (with the exception of the Phase IV NICE network management protocol). With this interoperability, you do not have to migrate your network --- or even an entire area --- all at once.
    For compatibility, DECnet-Plus systems can run two transports, both the DIGITAL Network Architecture (DNA) Network Services Protocol (NSP) and OSI transport protocol. In addition, DECnet-Plus end systems send routing packets and data link packets in either DECnet Phase V format or Phase IV format, depending on the phase of the receiving system.
  • Addressing options
    DECnet-Plus systems require a Phase IV-compatible address to communicate with Phase IV nodes. On the same DECnet-Plus system, you can also assign an OSI address that is not Phase IV-compatible.
    For details, see Section 1.3.
  • Node synonyms
    A node synonym is a Phase IV-style node name, between 1 and 6 characters long, that is unique within your namespace. (See Section 5.4 for a complete explanation of node synonyms.)
    The node synonym is required for Phase IV applications that can handle only a maximum of six-character node names.
    Use your Phase IV node name as your synonym. The default node synonym is the first six characters of your simple name, the string that follows the last period of your full name. For example, if you specify XYZ_CORP:.sales.east_coast.ElanaCole as a DECnet-Plus full name during the configuration procedure, your simple name is ElanaCole and your default node synonym is ElanaC.
    The configuration procedure gives you the option of specifying a different node synonym.
    You do not need a node synonym if:
    • Your network has made a full transition to all DECnet-Plus and other OSI-compliant systems.
    • These systems do not run any applications that are limited to six-character node names.

    Node synonyms allow for backward compatibility with older applications that cannot use long domain names. DECnet-Plus allows for node synonyms to provide backward compatibility DECnet Phase IV node names.
    DECnet programming interfaces $QIO and $IPC also provide long name support. User-written applications using these interfaces can use long names.<>
  • Coexistence of Phase V routing algorithm and Phase IV routing algorithm
    In DECnet-Plus, the Phase V routing algorithm, called the link state protocol, can coexist with the Phase IV routing algorithm, called the routing vector protocol. See Section 2.3.5 for details.
  • The Local namespace
    DECnet-Plus includes a Local namespace, independent of DECdns. DECnet-Plus also gives you an option of maintaining DECnet Phase IV functionality until your network makes the transition to DECnet Phase V. The Local namespace replaces functionality previously provided by the DECdns Local Naming Option (LNO). Depending on the number of address towers stored, the Local namespace is designed to scale to at least 100,000 nodes. For more information, refer to Section 1.5.1 and Section 5.1.

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