Patent ID: 8037188

Claim:
A method, operable by a first user terminal, for communicating across different networks, the method comprising: communicating in a call between the first user terminal and a second user terminal using a first communication link through a first network; negotiating between the first user terminal and the second user terminal to use a second communication link through a second network for the call, wherein the call originates at one of the first user terminal and the second user terminal; determining that the second network is preferred over the first network based on at least one of network preference criteria; establishing the second communication link through the second network between the first user terminal and the second user terminal while maintaining the first communication link through the first network between the first user terminal and the second user terminal; sending related data through the first communication link in the first network and through the second communication link in the second network such that the related data is for the call; dropping the first communication link; and continuing the call using the second communication link.