IGRP Routing Metric
IGRP uses a composite metric of internetwork delay, bandwidth, reliability, MTU, and load to determine the best path for each packet. The values are important, but because of the simple network topology of this lab environment, they will not be too critical for the lab objectives. However, they will be important when you implement route redistribution in Chapter 11, "Basic Route Redistribution and Static Routing." When redistributing routes from one routing protocol into another (RIP to IGRP, for example) you lose all metrics, so you will have to manually specify those values; for now, though, you will not change any metric values for IGRP