IGRP protocol

IGRP protocol.

The IGRP protocol is a routing protocol developed by Cisco and is proprietary to Cisco routers only. It is a link state protocol and has some significant advantages over the OSPF protocol.

Different from a distance vector protocol, IGRP only sends changes to its neighbors rather than transmitting the entire routing protocol to all routers on the network like RIP.

IGRP announces changes every 90 seconds by default.
IGRP must have an autonomous system number assigned to it for the routers to recognize whom they belong to.
T he IGRP protocol is versatile and can handle infinite complex topologies.
IGRP is Scalable and works well in very large networks.

The advantages of IGRP are many and include the following variables to determine composite metrics:

Bandwidth

Delay

Load

Reliability

Maximum Transfer Unit or (MTU) Size in bytes an interface can utilize

The IGRP protocol will create some bandwidth traffic on the network. However, in this situation, the traffic is minimal and will not seriously impact the overall network performance.