What is IGRP (Interior Gateway Routing Protocol)?
IGRP (Interior Gateway Routing Protocol) is an advanced distance-vector protocol developed by Cisco Systems in the mid-1980s, including some RIP errors.
Different bandwidths can be used to configure the metric value, such as the user’s network latency, bandwidth, and latency depending on the relative speed and capacity of the interface.
The load and reliability features are calculated based on the performance of the interface in actual network traffic management, although they are not enabled by default for routing decisions.
Like RIP, it uses IP broadcasts to forward routing information to neighboring routers. However, IGRP has been designated as its transport layer protocol.
To transmit network route information, UDP see is not connected to TCP. Since IGRP does not have a feedback mechanism, it works similarly to UDP.
It offers three significant improvements over the RIP protocol. First, the IGRP metric can support a network with a maximum of 255 router hop counts. Second, the IGRP metric can differentiate between the costs associated with sees of different types of connection media. Third, it should not wait for regularly scheduled times for updates but rather by sending information about changes in the network when it becomes available.
IGRP is a routing protocol based on distance vectors developed by CISCO.
Improved Scalability
On more extensive networks, routing has a maximum of 100 hops by default but can be configured with 255 hops.
Sophisticated Matrix
A composite metric for greater flexibility in route selection. Interconnection delay and bandwidth are used, and other parameters such as reliability, load, and MTU can be included.
Multiple Rotate support
It can hold six different cost paths between source and destination networks. Various routes can increase the available bandwidth or provide route redundancy. IGRP allows triggered updates.
Source: https://www.cisco.com/c/en/us/support/docs/ip/interior-gateway-routing-protocol-igrp/26825-5.html