Patent ID: 7697480

Claim:
A method for inter-network handoff of a voice call from a circuit switched network to a packet switched network, the method comprising: conveying forward link voice traffic to, and receiving reverse link voice traffic from, a subscriber unit via the circuit switched network in association with the call; determining to hand off the call; receiving, by the packet switched network notification of the need for a handoff; in response to receiving the handoff notification, conveying, by the packet switched network to the subscriber unit, a request to perform the handoff and establishing a communication session between the packet switched network and the subscriber unit; receiving reverse link voice traffic from the subscriber unit via the circuit switched network and via the packet switched network; when receiving reverse link voice traffic via the packet switched network and the circuit switched network, switching from the circuit switched network to the packet switched network for conveyance of the forward link voice traffic to the subscriber unit; and in response to switching the forward link voice traffic from the circuit switched network to the packet switched network, ceasing reception of reverse link voice traffic via the circuit switched network while continuing to receive reverse link voice traffic via the packet switched network.