Patent ID: 7092709

Claim:
A method of handing off a mobile station from an internal cellular communications network to an external mobile cellular communications network, the internal network being a packet switched network having a network controller, wherein the method comprising: allocating at least one cell of the internal cellular network as a border cell, the at least one cell being adjacent cells of the external cellular network; detecting the movement of said mobile station into said border cell; when said mobile station is in the border cell and before a hand-off requirement is determined, predicting using a prediction algorithm that an actual handoff is likely to be required using a set of predetermined parameters associated with said mobile station; generating an advance hand-off request when the prediction algorithm predicts that the actual hand-off is likely to be required; and setting up a communication channel in the external network in response to said advance hand-off request before the hand-off requirement for said mobile station is determined, said communication channel being ready for use by said mobile station when an actual hand-off is made.