System and method of handling IP layer mobility in a wireless network
View Patent ↗A system and method for facilitating the efficient operation of a mobile station as it transfers from communicating via one wireless data network to another. A session control node is coupled to the mobile node in such a manner that it selectively buffers data being transmitted to the mobile node, at least while the network transfer is being executed. When the mobile node had dropped its communication session with a first wireless network and established a new communication session with a second wireless network, the buffered data is read out and transmitted to the mobile node. The session control node may be coupled with a home network associated with the mobile node or a control node may be associated with the mobile node on an ad hoc basis.
1. A method for facilitating mobile-node communication in a multi-network communication system having a session control node, a current network through which communications are carried out and a new network, said method comprising:
routing, at the session control node, first mobile terminating data intended for a mobile-node to the current network;
receiving, at the session control node, a mobile-node-generated message identifying the new network with which communications are desired, the mobile-node-generated message transmitted from the mobile-node through the current network;
buffering, at the control node, second mobile-node terminating data responsive to reception, during said receiving, of the mobile-node-generated message, the buffering being capable of occurring without a communication session existing between a mobile node and a network;
routing the second mobile-node terminating data buffered in the buffering for communication to the new network; and
routing, at the session control node, third mobile terminating data intended for the mobile-node to the new network.
2. The method of claim 1 further comprising storing mobile-node temporary identifiers used by the current network and used by the new network.
3. The method of claim 1 wherein said receiving further comprises receiving a priority level associated with the mobile-node-generated message.
4. The method of claim 1 further comprising providing notification of start of the buffering of the second mobile node terminating data.
5. The method of claim 1 wherein said receiving further comprises receiving a new-network mobile-node temporary identifier.
6. An apparatus for facilitating network transfer of mobile-node communications in a multi-network communication system having a current network through which communications are carried out and a new network, said apparatus comprising:
a handoff detector configured to detect a transfer message that indicates the network-transfer to be appropriate;
a buffer configured to buffer first mobile-node terminating data during network transfer, responsive to the transfer message detected by said handoff detector, from the current network to the new network, the buffer being additionally configured to be able to buffer mobile-node terminating data, without a communication session existing between a mobile node and a network; and
a router configured to route second mobile-node terminating data to the current network prior to network transfer, said router further, configured to route, subsequent to initiation of the network transfer, the first mobile node terminating data buffered by the buffer and third mobile-node terminating data to the new network.
7. The apparatus of claim 6 wherein said handoff detector is further configured to detect a priority level associated with the transfer message.
8. The apparatus of claim 6 wherein said handoff detector is further configured to detect the transfer message that indicates the network transfer to be appropriate responsive to a content-type of the communications.
9. The apparatus of claim 6 further comprising a memory configured to store mobile-node temporary identifiers used by the current network and used by the new network.
10. The apparatus of claim 6 further comprising a notifier configured to provide notification of buffering of the first mobile-node terminating data by said buffer.
11. The apparatus of claim 6 wherein said handoff detector is further configured to detect a new-network mobile-node temporary identifier.
12. A method for facilitating network transfer of communication by a mobile node in a multi-network communication system having a session control node, a current network through which communication content is communicated and a new network, said method comprising:
receiving first communication content routed by the session control node through the current network;
determining that the network transfer from the current network to the new network is appropriate;
sending a transfer message indicating the network transfer to be appropriate, the transfer message causing buffering of second communication content during the network transfer of communications from the current network to the new network, the buffering during network transfer including the capability of buffering mobile-node terminating data without the existence of a communication session between a mobile node and a network;
receiving play-out of the buffered second communication content communicated subsequent to the transfer, through the new network and;
receiving third communication content routed by the session control node through the new network subsequent to receiving the buffered second communication content.
13. The method of claim 12 wherein said determining comprises determining that the network transfer is appropriate comprises determining that the network transfer is necessary.
14. The method of claim 12 wherein said determining comprises determining that the network transfer is desirable.
15. The method of claim 12 wherein said sending further comprises sending an identity of the new network.
16. The method of claim 12 wherein said receiving further comprises receiving confirmation that the session control node has begun the buffering of the second communication content by way of the current network.
17. An apparatus for facilitating network transfer of communication by a mobile node in a multi-network communication system having a session control node, a current network through which communication content is communicated and a new network, said apparatus comprising:
a transfer determiner configured to determine that the network transfer from the current network to the new network is appropriate;
a transfer message generator configured to generate a transfer message indicating the network transfer to be appropriate, the transfer message, when sent, causing buffering of second communication content during the network transfer of communications from the current network to the new network, the buffering during network transfer being capable of occurring without the existence of a communication session between a mobile node and a network; and
a receiver configured to receive first communication content routed by the session control node through the current network, and, subsequent to the transfer, receive through the new network play-out of the buffered second communication content and receive third communication content routed by the session control node, through the new network.
18. The apparatus of claim 17 wherein said transfer message generator is further configured to generate a transfer message that includes a new-network identity.
19. The apparatus of claim 17 wherein said transfer message generator is further configured to identify a priority level associated with the network transfer.