Introduction to VTAM resource definition

This topic gives an overview of VTAM® resource definition and presents general information on:
  • Major nodes
  • Routing functions
  • Tables
  • Coding conventions, formats, and procedures
Defining a single-domain network to VTAM involves defining the following resources:
  • Adjacent control point major nodes
  • Application program major nodes
  • Channel-attachment major nodes
  • External communication adapter major nodes
  • Local non-SNA major nodes
  • Local SNA major nodes
  • LU group major nodes
  • Model major nodes
  • NCP major nodes
  • Switched major nodes
  • Path statements 1
  • Transmission group profiles
  • Tables
Defining a multiple-domain network to VTAM also involves defining:
  • Adjacent SSCP tables 1
  • Cross-domain resource manager major nodes
  • Cross-domain resource major nodes 2
  • Network node server lists
  • Transport resource list

When you use SNA network interconnection, you might also have to redefine existing major node definitions.

VTAM uses tables for routing, to begin and end sessions, and to define messages and certain operator commands and to suppress messages. You can create, replace, or modify these tables while VTAM is running.

VTAM also provides a filter for session awareness (SAW) data that is passed to communication network management (CNM) application programs, such as NetView®. You can create, modify or replace the filter while VTAM is running.

After you define a network, you can use dynamic reconfiguration to add, move, or delete resources attached to an NCP or to add or delete locally attached logical units. In addition, you can dynamically change the values of certain operands.

See z/OS Communications Server: SNA Network Implementation Guide for information about the methods of dynamic reconfiguration.

1 These definition statements, along with dynamic reconfiguration and dynamic path update, are described in Routing and dynamic reconfiguration.
2 The cross-domain major node is also used to predefine independent LUs in a boundary-attached subarea network.