Routes that are advertised through the Border Gateway Protocol (BGP) are commonly aggregated to
minimize the number of routes that are used and reduce the size of global routing tables. However,
common route aggregation can obscure more specific routing information that is more accurate but not
necessary to forward packets to their destinations. Routing accuracy is obscured by common route
aggregation because a prefix that represents multiple addresses or hosts over a large topological area
cannot be accurately reflected in a single route. Cisco IOS software provides several methods in which
you can originate a prefix into BGP. The existing methods include redistribution and using the network
or aggregate-address command. These methods assume the existence of more specific routing
information (matching the route to be originated) in either the routing table or the BGP table.

The BGP Conditional Route Injection feature allows you to originate a prefix into a BGP routing table
without the corresponding match. This feature allows more specific routes to be generated based on
administrative policy or traffic engineering information in order to provide more specific control over
the forwarding of packets to these more specific routes, which are injected into the BGP routing table

Release

Modification

12.0(14)ST

This feature was introduced.

12.0(22)S

This feature was integrated.