IGRP is a proprietary Cisco Systems protocol that was developed to improve on RIP.
IGRP is also a distance-vector protocol, but it has the following capabilities:
- Load: The protocol takes the load placed on the network and routers into consideration when calculating the fastest path from point to point.
- Delay: Any network delay, such as a congested router, is part of the calculation process.
- Reliability: The protocol assesses the reliability of certain links. If the link is often down, the reliability of that link can be taken into consideration.
- Bandwidth: The protocol considers the available bandwidth on a given link when assessing the fastest path.