Avaya Configuring XNS Services User Manual download pdf (Page 29)

XNS Overview

303548-A Rev 00

1-13

Configurable Split Horizon

The purpose of the Split Horizon algorithm is to prevent circular routes and reduce

network traffic. The Bay Networks implementation of Split Horizon excludes

RIPs and SAPs learned from a neighbor when forwarding RIP and SAP updates to

that neighbor. Split Horizon is enabled by default for each interface.

If you have a star or non-fully meshed Frame Relay topology, you may need to

disable Split Horizon on certain interfaces for the routers to learn about the other

networks.

A fully meshed network is a WAN in which all nodes have a logically direct

connection to each other. In a fully meshed environment, all routers will learn

about all networks and have complete routing tables. Figure 1-4

shows a sample

fully meshed network with Split Horizon enabled.

Figure 1-4. Split Horizon Enabled in a Fully Meshed Network

Caution:

We advise you not to disable Split Horizon unless it is absolutely

necessary.

Network

Split Horizon enabled on this

interface to eliminate all

redundant RIP and SAP traffic.

Network

Router C

Router B

Router A

WAN

XNS0004A

1 ... 28 29 30 ... 72

No comments

Avaya Configuring XNS Services User Manual Page 29