Patent ID: 8451840

Claim:
A first node for a packet-switched network having a protocol stack comprising an upper layer and a lower layer, the first node comprising: a transceiver adapted to receive incoming packets and transmit outgoing packets; and a processor adapted to process the incoming packets and generate the outgoing packets, wherein: the first node is adapted to establish an upper-layer session with a second node in which packets are transmitted between the first node and the second node via the packet-switched network during which the first node has a first lower-layer address; the first node is adapted to switch from the first lower-layer address to a second lower-layer address, different from the first lower-layer address, while maintaining the upper-layer session; the first node has a first node's identifier adapted for the second node to use to identify the upper-layer session both (i) when the first node has the first lower-layer address and (ii) when the first node has the second lower-layer address; the first node has no home lower-layer address; when the first node has the first lower-layer address, packet from the second node are transmitted to the first node via a first router; and if the first node not receive an identifier for the second node, then, after the first node switches from the first lower-layer address to the second lower-layer address, the first node transmits one or more messages to the first router to instruct the first router to forward, to the second lower-layer address, a subsequently received packet addressed to the first lower-layer address.