To display BGP communities in the format AA:NN (AS-community number/2-byte number), use the ip bgp-community new-format command in global configuration mode.To re-enable the previous display format for BGP communities (NN:AA), use the no form of this command.
RFC 1997, BGP Communities Attribute specifies that a BGP community is made up of two parts that are 2 bytes long. The first part is the autonomous system number and the second part is a 2-byte number. In the most recent version of the RFC, a community is of the form AA:NN. The Cisco default community format is one 32-bit number. The ip bgp-community new-format command changes the community format to AA:NN to conform to RFC 1997.
Router# show ip bgp 10.0.0.0
BGP routing table entry for 10.0.0.0/8, version 4
10.0.33.35 from 10.0.33.35 (192.168.3.3)
0.0.0.0 from 0.0.0.0 (10.0.33.34)