|  | 1.4 | Routing Protocol
| 1.4.8 | IGRP overview

IGRP is a distance vector routing protocol developed by Cisco. IGRP sends routing updates at 90-second intervals that advertise networks for a particular autonomous system. The following are some key characteristics of IGRP. Design emphasis: Versatility to automatically handle indefinite, complex topologies. Flexibility for segments having different bandwidth and delay characteristics. Scalability to function in very large networks. IGRP may use a combination of variables to determine a composite metric. Variables IGRP uses include: Bandwidth Delay Load Reliability Maximum transmission unit (MTU)