Patent ID: 8355379

Claim:
A communication system comprising: a core network for routing data between first and second radio networks; the first radio network supporting a first air interface standard and comprising first means for receiving a handover preference message from the core network and for determining a handover in response to the handover preference message; the second radio network supporting a second air interface standard and comprising second means for receiving the handover preference message from the core network and for determining a handover in response to the handover preference message; and setting means for setting a handover preference information element of the handover preference message such that, when the first means and second means receive the same handover preference information element, the first means biases handover decisions towards a remote station being supported by the first radio network and the second means biases handover decisions towards the remote station being supported by the second radio network such that the setting means controls any network in the system, using the same information element, to exhibit a preference to remain attached to an access layer of a radio network currently supporting the remote station instead of handing over in accordance with an interlayer handover preference for a specific access layer in a different radio network, wherein the first means is arranged to bias handover decisions towards a remote station being supported by the first radio network by initiating a handover to the second radio network only if a service of the remote station cannot be supported by the first radio network, and wherein the first means is arranged to determine a handover for a service in response to a nominal handover preference if no handover preference message is received for the service, wherein the nominal handover preference for a service type is determined in response to at least one characteristic of a radio access bearer supporting the service type.