Communication system and method therefor

• US 20040010615A1
• Filed: 06/30/2003
• Published: 01/15/2004
• Est. Priority Date: 05/24/2000
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Lach, Hong-Yon, Ernst, Thierry
• Granted Patent: US 7,421,512 B2
• Time in Patent Office: Days
• US Class Current: 709/238
• CPC Class Codes: H04L 12/189 in combination with wireless systems selective distribution or broadcast in wireless communication networks H04W4/06
• CPC Class Codes: H04W 8/14 between corresponding nodes
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

Known protocols for supporting mobility in relation to Internet Protocol (IP) networks are not able to efficiently support distribution of Binding Update messages to Correspondent Nodes (104) in a set of fixed IP networks (102). Consequently, the present invention makes usse of a multi-cast service provided by the IPv6 protocol in order to deliver Binding Update messages to the Correspondent Nodes (104). The use of the multi-cast service to deliver Binding Update messages avoids a proliferation of such messages which would occur under know protocols requiring a mobile node (106,107) to send the Binding Update message to each Correspondent Node (104). Consequently, use of bandwith in the set of fixed IP networks (102) is more efficient.

Claims

1. A communications system (100) comprising:

a mobile node (106, 107) capable of mobility relative to a first network (102) having a plurality of correspondent nodes(104), a first interfacing node (108) and a second interfacing node(110), the plurality of correspondent nodes (104) being capable of sending data to the mobile node (106, 107) via the first interfacing node (108), the mobile node (106, 107) being capable of moving from a first location associated with the first interfacing node (108) of the first network (102) to a second location associated with the second interfacing node (110) of the first network (102), wherein

a number of the plurality of correspondent nodes (104) form a multicast group supported by a multicast service, the multicast service being arranged to receive updating data corresponding to a topological point of coupling of the mobile node (106, 107) to the first network and transmit the updating data to the number of the plurality of correspondent nodes (104) forming the multicast group in response to a movement of the mobile node (106, 107) from the first location to the second location.

2. A system (100) as claimed in claim 1, wherein the multicast service establishes a communications tree (300) between the mobile node (106, 107) and the number of the plurality of correspondent nodes (104) in the multi-cast group, a single copy of the updating data being sent on any branch of the communications tree (300).

3. A system (100) as claimed in claim 1, wherein the multicast service establishes a communications tree (300) between a node (108, 110) in the first network and the number of the plurality of correspondent nodes (104) in the multi-cast group, a single copy of the updating data being sent on any branch of the communications tree (300).

4. A system (100) as claimed in claim 3, wherein the node (108, 110) in the first network (102) is the first interfacing node (108).

5. A system (100) as claimed in claim 1, wherein the mobile node (106, 107) is a mobile interfacing node (107) coupled to a plurality of mobile network nodes (402) to form a mobile network (400) capable of mobility relative to the first network (102), the plurality of correspondent nodes (104) being capable of communicating data with at least one of the plurality of mobile network nodes (402) via the mobile interfacing node (107) and the first interfacing node (108) of the first network (102).

6. A system (100) as claimed in claim 5, wherein the plurality of correspondent nodes (104) is capable of communicating data with the at least one of the plurality of mobile network nodes (402) via the mobile interfacing node (107) and the second interfacing node (110) instead of the first interfacing node (108) of the first network (102) in response to the mobile network (400) moving from the first location to the second location.

7. A system (100) as claimed in claim 6, wherein at least one of the plurality of correspondent nodes (104) is arranged to transmit data bearing a destination IP address corresponding to a network prefix of the mobile interfacing node (107) contained in the updating data to the mobile interfacing node (107).

8. A system (100) as claimed in claim 7, wherein the at least one of the plurality of correspondent nodes (104) is arranged to send data containing the destination address bearing the network prefix of the mobile network (400) towards the second interfacing node (110).

9. A method of switching between a first access point and a second access point of a first network (102), the first network (102) having a first interfacing node(108), a second interfacing node (110) and a plurality of correspondent nodes (104) capable of communicating with a mobile node (106, 107), the method comprising the steps of:

registering (200, 500) the mobile node (106, 107) with the first interfacing node (108) of the first network (102) when residing at a first location;

registering (210, 510) the mobile node (106, 107) with the second interfacing node (110) of the first network (102) associated with a second location in response to the first network (102) moving from the first location to the second location;

transmitting (212, 512) updating data to a multicast service, and

transmitting (214, 514) the updating data to a number of the plurality of correspondent nodes subscribing to the multicast service.

10. A method as claimed in claim 9, wherein the mobile node (106, 107) is a mobile interfacing node (107) coupled to a plurality of mobile network nodes (402) to form a mobile network (400) capable of mobility relative to the first network (102), the plurality of correspondent nodes (104) being capable of communicating data with at least one of the plurality of mobile network nodes (402) via the mobile interfacing node (107) and the first interfacing node (108) of the first network (102).

11. A method as claimed in claim 10, wherein the plurality of correspondent nodes (104) is capable of communicating data with the at least one of the plurality of mobile network nodes (402) via the mobile interfacing node (107) and the second interfacing node (110) instead of the first interfacing node (108) of the first network in response (102) to the mobile network (400) moving from the first location to the second location.

12. A method as claimed in claim 9, wherein the multicast service establishes a communications tree (300) between the mobile node (106, 107) and the number of the plurality of correspondent nodes (104) in the multi-cast group, a single copy of the updating data being sent on any branch of the communications tree(300).

13. A method as claimed in claim 10, wherein at least one of the plurality of correspondent nodes (104) is arranged to transmit data bearing a destination IP address corresponding to a network prefix of the mobile interfacing node (107) contained in the updating data to the mobile interfacing node (107).

14. A method as claimed in claim 13, wherein the at least one of the plurality of correspondent nodes (104) is arranged to send data containing the destination address bearing the network prefix of the mobile network (400) towards the second interfacing node(110).

15. A mobile node (106, 107) apparatus for coupling to a first network (102) at a first topological point of coupling corresponding to a first location and routing communications from a correspondent node (104) in the first network (102) via a first interfacing node (108) of the first network(102), the apparatus comprising:

a processor unit (700) coupled to a storage unit (702) and a transceiver unit (704) for communicating with the first interfacing node (108) of the first network (102) at a first location;

the processor unit (700) being adapted to transmit updating data to a multicast service of the first network (102) in response to movement of the mobile node (106, 107) from the first location to a second topological point of coupling corresponding to a second location.

16. An apparatus (106, 107) as claimed in claim 15, wherein the mobile node (106, 107) is a mobile interfacing node (107) coupled to a plurality of mobile network nodes (402) to form a mobile network (400) capable of mobility relative to the first network(102), the correspondent node (104) being capable of communicating data with at least one of the plurality of mobile network nodes (402) via the mobile interfacing node (107) of the mobile network (400) and the first interfacing node (108) of the first network (102).

17. An apparatus as claimed in claim 16, wherein the correspondent node (104) is capable of communicating data with at least one of the plurality of mobile network nodes (402) via the mobile interfacing node (107) and a second interfacing node (110) at the second location instead of the first interfacing node (108) in response to the mobile network (400) moving from the first location to the second location.

18. A network entity apparatus (104, 108) for a first network (102) comprising:

a processor unit (700) coupled to a storage unit (702) and a transceiver unit (704) for communicating with a mobile node(106, 107), wherein

the processor unit (700) comprises a registration unit coupled to the transceiver unit (704) and arranged to register with a multicast service so as to become a member of a multicast group, and receive updating data from the multicast service.

19. An apparatus (104, 108) as claimed in claim 18, wherein the multicast service establishes a communications tree (300) between the mobile node (106, 107) and a number of a plurality of correspondent nodes (104) in the multicast group, a single copy of the updating data being sent on any branch of the communications tree (300).

20. An apparatus (104, 108) as claimed in claim 18, wherein the registration unit receives the updating data from the multicast service in response to movement of the mobile node (106, 107) from a first location to a second location.

21. An apparatus (104, 108) as claimed in claim 18, wherein the mobile node (106, 107) is a mobile interfacing node (107) coupled to a plurality of mobile network nodes (402) to form a mobile network (400) capable of mobility relative to the first network (102), a plurality of correspondent nodes (104) being capable of communicating data with at least one of the plurality of mobile network nodes (402) via a first interfacing node (108) of the first network (102) at a first location and the mobile interfacing node (107).

22. An apparatus (104, 108) as claimed in claim 21, wherein the plurality of correspondent nodes (104) is capable of communicating data with the at least one of the plurality of mobile network nodes (402) via the mobile interfacing node (107) and a second interfacing node (110) at a second location of the first network (102) instead of the first interfacing node (108) in response to the mobile network (400) moving from the first location to the second location.

23. A communication system (100) comprising:

a mobile interfacing node (107) coupled to a plurality of mobile network nodes (402) to form a mobile network (400) capable of mobility relative to a first network(102), the first network (102) having a plurality of correspondent nodes(104), a first interfacing node (108) and a second interfacing node( 110), the mobile network (102) being capable of moving from a first location associated with the first interfacing node (108) of the first network (102) to a second location associated with the second interfacing node (110) of the first network(102), the plurality of correspondent nodes (104) being capable of communicating data with at least one of the plurality of mobile network nodes (402) via the mobile interfacing node (107) and the first interfacing node(108), wherein at least one of the plurality of correspondent nodes (104) is arranged to receive updating data indicative of a current topological point of coupling of the mobile interfacing node (107) to the first network (102) and forward data bearing a destination address corresponding to a network prefix of the mobile interfacing node (107) to the second interfacing node (110) in response to the mobile network (400) moving from the first location to the second location, the second location corresponding to the current topological point of coupling of the mobile interfacing node (107) to the first network (102).

24. A system (100) as claimed in claim 23, wherein a number of the plurality of the correspondent nodes (104) form a multicast group supported by a multicast service, the multicast service being arranged to receive the updating data and transmit the updating data to the number of correspondent nodes (104) forming the multicast group in response to movement of the mobile network (400) from the first location to the second location.

25. A method of switching between a first access point and a second access point of a first network(102), the first network (102) having a first interfacing node(108), a second interfacing node (110) and a plurality of correspondent nodes (104) capable of communicating with at least one of a plurality of mobile network nodes (402) via the first interfacing node (108) and a mobile interfacing node (107) coupled to the plurality of mobile network nodes(402), the plurality of mobile network nodes (402) and the mobile interfacing node (107) being inter-coupled to form a mobile network(400), the mobile network (400) being capable of moving from a first location associated with the first interfacing node (108) of the first network (102) to a second location associated with the second interfacing node (110) of the first network (102), wherein the method comprises the steps of:

registering (500) the mobile interfacing node (107) with the first interfacing node (108) of the first network (102) when residing at the first location;

registering (510) the mobile interfacing node (107) with the second interfacing node (110) of the first network (102) associated with a second location in response to the mobile network (102) moving from the first location to the second location;

transmitting updating data to a number of the plurality of correspondent nodes (104) indicative of a current topological point of coupling of the mobile interfacing node (107) to the first network(102);

forwarding (518) data bearing a destination address corresponding to a network prefix of the mobile interfacing node (107) to the second interfacing node(110), the second location corresponding to the current topological point of coupling of the mobile interfacing node (107) to the first network(102).

26. A method as claimed in claim 25, further comprising the steps of:

transmitting (512) the updating data to a multicast service, and

transmitting (514) the updating data to the number of the plurality of correspondent nodes (104) using the multicast service.

27. A correspondent node (104) apparatus for a first network (102) having a first interfacing node (108) corresponding to a first location and a second interfacing node (110) corresponding to a second location, the apparatus (104) comprising:

a processor unit (700) coupled to a storage unit (702) and a transceiver unit (704) for communicating with a mobile network node (402) coupled to a mobile interfacing node(107), wherein the processor unit (700) comprises a binding unit coupled to the transceiver (704) and arranged to receive updating data for indicating a current topological point of coupling of the mobile interfacing node (107) to the first network(102), the processor unit (700) being arranged to forward data bearing a destination address corresponding to a network prefix of the mobile interfacing node (107) for onward transmission of the data to the second interfacing node (110) in response to the mobile network (400) moving from the first location to the second location, the second location corresponding to the current topological point of coupling of the mobile interfacing node (107) to the first network (102).