1. A communication network comprising: a plurality of border controllers; a first packet voice network; a second packet voice network coupled to the first packet voice network by the plurality of border controllers; and a master border controller coupled to the plurality of border controllers and coupled to the first packet voice network and the second packet voice network; wherein the master border controller, in response to receiving a plurality of update messages from the plurality of border controllers, processes the update messages to determine operational states of the plurality of border controllers, and responsive to receiving a query from a first switch in the first packet voice network for a call between the first and second packet voice networks, processes the query to determine a first border controller for the call of the plurality of border controllers based on the operational states of the plurality of border controllers, and transfers a response to the first switch in the first packet network wherein the response indicates the first border controller.