This command has no arguments. auto-summary is enabled by default.
Purpose: When auto-summary is enabled, routes injected into BGP via redistribution are summarized on a classful boundary. A 32-bit IP address consists of a network address and a host address. The subnet mask determines the number of bits used for the network address and the number of bits used for the host address. The IP address classes have a natural or standard subnet mask, as shown in Table 2-1.
|Class||Address Range||Natural Mask|
|A||184.108.40.206 to 220.127.116.11||255.0.0.0 or /8|
|B||18.104.22.168 to 22.214.171.124||255.255.0.0 or /16|
|C||126.96.36.199 to 188.8.131.52||255.255.255.0 or /24|
|Reserved addresses include 184.108.40.206, 220.127.116.11, ...|