Communications Server for z/OS V1R7 TCP/IP Implementation, Volume 1: Base Functions, Connectivity, and Routing

© Copyright IBM Corp. 2006. All rights reserved. 139

Chapter 5. Routing

One of the major functions of a network protocol such as TCP/IP is to efficiently interconnect

a number of disparate networks. These networks may include LANs and WANs, fast and

slow, reliable and unreliable, inexpensive and expensive connections. To interconnect these

networks, some level of intelligence is needed at the boundaries to look at the data packets

as they pass and make rational decisions as to where and how they should be forwarded.

This is known as IP routing. In this chapter we look at the various types of IP routing

supported in a z/OS environment.

This chapter includes the following.

5

Section Topic

5.1, “Overview” on page 140 Discusses the basic concepts of IP routing

5.2, “Why IP routing is important” on

page 154

Discusses key characteristics of IP routing and why it

may be important in your environment

5.4, “The common design scenarios for

IP routing” on page 155

Presents commonly implemented IP routing design

scenarios, their dependencies, advantages,

considerations, and our recommendations

5.5, “How IP routing is implemented” on

page 160

Presents selected implementation scenarios, tasks,

configuration examples, and problem determination

suggestions