Mobility in ip without mobile ip

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 receive, from a second node, (i) a current lower-layer address of the second node and (ii) an identifier for the second node;
• if the first node does not have an existing association between the second node's identifier and any lower-layer address of the second node, then the first node (i) associates the second node's identifier with the current lower-layer address of the second node and (ii) establishes an upper-layer session with the second node, wherein packets transmitted by the first node to the second node are addressed to the current lower-layer address for the second node;
• and
• if the first node does have an existing association between the second node's identifier and a previous lower-layer address of the second node, different from the current lower-layer address of the second node, then the first node (i) updates the existing association such that the second node's identifier is associated with the current lower-layer address of the second node and (ii) addresses packets to be transmitted to the second node with the current lower-layer address of the second node.

A router for a packet-switched network having a protocol stack comprising an upper layer and a lower layer, the router 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 router is adapted to support an upper-layer session between a first node and a second node in which packets are transmitted between the first node and the second node via the packet-switched network;
• the first node is adapted to establish the upper-layer session with the second node 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 with the second node;
• and
• the first node has no home lower-layer address.