One or more gateways (107 and 108) as serve to interconnect the discrete call facilitation platforms (403 and 404) of a given communication network with an external communication network (109) as provided with the routing addresses of such discrete call facilitation platforms. The discrete call facilitation platforms, however, are not provisioned in a reciprocal fashion. Instead, the discrete call facilitation platforms are only provided with a subset of available gateway addresses. In a preferred approach, this is accompanied by less-than-fully-meshed connectivity between the gateways and the discrete call facilitation platforms.