Cisco Systems 78-11741-02 manual Configuring Interpacket Delay, Connecting RIP to a WAN, IPC-208

Configuring Routing Information Protocol

RIP Configuration Task List

Configuring Interpacket Delay

By default, the software adds no delay between packets in a multiple-packet RIP update being sent. If you have a high-end router sending to a low-speed router, you might want to add such interpacket delay to RIP updates, in the range of 8 to 50 milliseconds. To do so, use the following command in router configuration mode:

Command	Purpose
Router(config-router)# output-delaydelay	Adds interpacket delay for RIP updates sent.

Connecting RIP to a WAN

Routers are used on connection-oriented networks to allow potential connectivity to many remote destinations. Circuits on the WAN are established on demand and are relinquished when the traffic subsides. Depending on the application, the connection between any two sites for user data could be short and relatively infrequent.

There are two problems using RIP to connect to a WAN:

•Periodic broadcasting by RIP generally prevents WAN circuits from being closed.

•Even on fixed, point-to-point links, the overhead of periodic RIP transmissions could seriously interrupt normal data transfer because of the quantity of information that passes through the line every 30 seconds.

To overcome these limitations, triggered extensions to RIP cause RIP to send information on the WAN only when there has been an update to the routing database. Periodic update packets are suppressed over the interface on which this feature is enabled. RIP routing traffic is reduced on point-to-point, serial interfaces. Therefore, you can save money on an on-demand circuit for which you are charged for usage. Triggered extensions to RIP partially support RFC 2091, Triggered Extensions to RIP to Support Demand Circuits.

To enable triggered extensions to RIP, use the following commands in global configuration mode:

	Command		Purpose
Step 1
	Router(config)# interface	serial controller-number	Configures a serial interface.
Step 2
	Router(config-if)# ip rip	triggered	Enables triggered extensions to RIP.

Cisco IOS IP Configuration Guide

IPC-208