Patent ID: 7848315

Claim:
A method of transmitting telephone conversations over a telephone system comprising a number of voice circuit switches each connected to a packet-switched data communications network by respective gateways, said method comprising the steps of: establishing a first call path for voice data and control data between a calling party and a called party through an end ingress gateway to the packet-switched network, an end egress gateway from the packet switched network and at least one intermediate voice circuit switch with an egress gateway from the packet-switched network and an ingress gateway to the packet-switched network, the first call path comprising a concatenation of packet-switched and circuit-switched segments; establishing a second call path for voice data and control data directly over the packet-switched network between the end ingress gateway, being the gateway first encountered on the call path emanating from the calling party, and the end egress gateway, being the final gateway encountered on the call path before reaching the called party, wherein the second call path bypasses the intermediate voice circuit switch and the intermediate voice circuit switches ingress and egress gateways; after establishing the first call path, transmitting voice data over the first call path; after establishing the second call path and after the called party has answered, transmitting voice data over the second call path directly between the end ingress gateway and the end egress gateway instead of via the first call path; maintaining the first call path for mid-call and end-of-call signaling that involves the intermediate voice circuit switch and for mid-call voice data; and continuing to transmit voice data over the first call path in the event that the second call path is not available.