IP Routing Fundamentals

Convergence Using EIGRP

Convergence in an EIGRP network can be quite complicated. Part of this complexity is due to Cisco's standard of supporting up to six parallel routes to all destinations. Although this standard has helped make Cisco the market leader in internetworking products, it makes it more difficult to explain internetworking topics. For the sake of explaining the theory and mechanics of convergence, the examples in this section assume that a router remembers only a single primary route and one alternative (feasible successor) route.

The network illustrated in Figure 11-1 is a relatively small EIGRP network with five separate regions and a modest degree of route redundancy. This network is used to illustrate how EIGRP converges using ...