BGP advertises multiple add-paths based on community value

You can define a policy to identify eligible multiple path prefixes based on community values. BGP advertises these community-tagged routes in addition to the active path to a given destination. If the community value of a route does not match the community value defined in the policy, then BGP does not advertise that route. This feature allows BGP to limit the number of multiple paths that are processed and not advertise more than 20 paths to a given destination. You can limit and configure the number of prefixes that BGP considers for multiple paths without actually knowing the prefixes in advance. Instead, a known BGP community value determines whether or not a prefix is advertised.