Let's say you have one or more IP routes that you don't want appearing in a router's IP routing table. The reason might be for security or for router performance, as a couple of examples. With OSPF, there are three primary ways to accomplish this route filtering:

• Filter a route coming in from another autonomous system, as part of a redistribution configuration.
• Filter a route between areas, using a filter list.
• Filter a route from being installed in an single router's IP routing table, using a distribute list.

This video discusses these three approaches, and it demonstrates the configuration of two of these approaches (because redistribution is a topic unto itself).

Enjoy the video!

Kevin Wallace, CCIEx2 (R/S and Collaboration) #7945