Patent ID: 8565139

Claim:
A method of providing communication between mobile devices within a wide area network using IP unicast communication and a wireless local area network using IP multicast communication, wherein the wide area network and the wireless local area network are coupled by a gateway component, the method comprising: storing a public IP address of the gateway component within a mobile device; establishing data communication between the mobile device and the wireless local area network, a first unicast IP address being acquired by the mobile device in response to establishing the data communication with the wireless local area network; storing the first unicast IP address within the mobile device; joining the mobile device with a multicast group within the wireless local area network and registering the mobile device with the multicast group using a predetermined multicast IP address as a destination IP address and the first unicast IP address as a source address; disconnecting the mobile device from data communication within the wireless local area network, thereby releasing the first unicast IP address acquired by the mobile device; establishing data communication between the mobile device and the wide area network, a second unicast IP address being acquired by the mobile device in response to establishing the data communication with the wide area network; storing the second unicast IP address with the public IP address of the gateway component and the first unicast IP address within the mobile device; and automatically sending a message to the public network address of the gateway component, via the wide area network, to specify the second unicast IP address as the source address for the mobile device within the multicast group.