IGP Route Redistribution,
Route Summarization, and
Default Routing
This chapter covers several topics related to the use of multiple IGP routing protocols. IGPs can
use default routes to pull packets toward a small set of routers, with those routers having learned
routes from some external source. IGPs can use route summarization with a single routing
protocol, but it is often used at redistribution points between IGPs as well. Finally, route
redistribution by definition involves moving routes from one routing source to another. This
chapter takes a look at each topic.
For perspective, note that this chapter includes coverage of RIPv2 redistribution topics. Even
though RIPv2 has been removed from the CCIE Routing and Switching qualifying exam
blueprint, it is still possible that you might see exam questions on redistribution involving
RIPv2. Therefore, this chapter includes coverage of that topic.