Route Summarization

Route Summarization refers to the process of combining multiple individual network prefixes into a broader route. This generally requires the relevant IP networks to share a common prefix that can be represented by a single summary route. Routers can then advertise one aggregated route instead of distributing numerous specific routes. This reduces routing table size and the amount of routing information exchanged between routers. In large enterprise, campus and service provider networks, Route Summarization can improve scalability and reduce processing requirements on network devices. Changes within a summarised network range can also remain isolated from other parts of the network. The method is commonly used with routing protocols such as OSPF, IS-IS, EIGRP and BGP.