Extended Community Processing
When BGP receives the extended community attribute in a route from its neighbor, it validates the community syntax. If the community is syntactically valid, the inbound neighbor route-policy is applied to the route. The inbound route-policy may contain extended-community statements in match block (in other words, an or/and set) of the policy. If the route is not rejected by the inbound route-policy, it is added to the LocRIB of the BGP along with the extended community. The detail option of the show bgp routes command displays the routes with the extended community attribute if they are present in that route's path attribute.