Publishing node information

• US 20020075807A1
• Filed: 12/14/2000
• Published: 06/20/2002
• Est. Priority Date: 09/14/2000
• Status: Active Grant

• Current Assignee: Raytheon BBN Technlogies Corp. (Rtx Corporation)
• Original Assignee: BBN Technologies (Rtx Corporation)
• Inventors: Troxel, Gregory Donald, Gesler, Gwendolyn Jean
• Granted Patent: US 6,996,084 B2
• Time in Patent Office: Days
• US Class Current: 370/238
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 61/35 involving non-standard use of addresses for implementing network functionalities, e.g. coding subscription information within the address or functional addressing, i.e. assigning an address to a function
• CPC Class Codes: H04L 61/5084 Providing for device mobility network addressing or numbering for mobility support in wireless networks H04W8/26; mobile IP H04W80/04
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/164 at the network layer
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 40/246 Connectivity information discovery
• CPC Class Codes: H04W 40/248 Connectivity information update
• CPC Class Codes: H04W 40/26 for hybrid routing by combining proactive and reactive routing
• CPC Class Codes: H04W 40/32 for defining a routing cluster membership
• CPC Class Codes: H04W 8/02 Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
• CPC Class Codes: H04W 8/082 for traffic bypassing of mobility servers, e.g. location registers, home PLMNs or home agents
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

The invention can enable routers in a region to share information about nodes on foreign sub-networks. The information includes the nodes'"'"' and routers'"'"' respective network layer addresses. Upon receiving a message addressed to one of the nodes, a router can tunnel the message to a router on the node'"'"'s foreign sub-network for subsequent de-tunneling and delivery to the node.

Claims

1. A method for use in delivering network messages, the method comprising:

(a) receiving at a first router a network layer address of a node, the first router and the node both being on a sub-network that is topologically foreign with respect to the network layer address of the node;

(b) sending from the first router the received network layer address of the node and a network layer address of the first router toward a second router, the second router being on a sub-network that is topologically foreign with respect to the network layer address of the node;

(c) receiving at the first router a message tunneled toward the first router by the second router in response to receiving a message at the second router having a destination address of the node;

(d) de-tunneling the tunneled message; and

(e) sending the de-tunneled message toward the node;

whereby (a)-(e) proceed without requiring communication with any node on a sub-network that is a topologically home sub-network with respect to the network layer address of the node

2. The method of claim 1, wherein the second router comprises a router in a defined collection of routers.

3. The method of claim 2, wherein the defined collection of routers comprise routers within an autonomous system.

4. The method of claim 3, wherein the defined collection of routers within an autonomous system comprise routers within an OSPF (Open Short Path First) system.

5. The method of claim 2, wherein the defined collection of network nodes comprises routers in more than one autonomous system.

6. The method of claim 2, wherein sending the received network layer address of the node and a network layer address of the first router toward a second router comprises flooding the defined collection of routers with the received network layer address of the node and the network layer address of the first router.

7. The method of claim 1, wherein the network layer address of the node comprises an Internet Protocol address.

8. The method of claim 1, wherein the node comprises a wireless node.

9. The method of claim 1, further comprising determining whether to send the received network layer address of the node and a network layer address of the first router.

10. The method of claim 9, wherein determining comprises comparing a time elapsed since a previous sending of a received network layer address of a node with a holdoff period.

11. The method of claim 1, further comprising advertising availability of the router to serve mobile nodes.

12. The method of claim 1, wherein sending the received network layer address of the node and the network layer address of the first router toward a second router comprises sending without tunneling.

14. The method of claim 13, wherein the network layer address comprises an Internet Protocol address.

15. The method of claim 13, wherein the collection of routers comprise routers in an autonomous system.

16. The method of claim 13, wherein the collection of routers comprise routers in more than one autonomous system.

17. The method of claim 13, further comprising:

modifying the routing tables of routers receiving the flooded information to include entries for the mobile nodes.

19. The computer program of claim 18, wherein the second router comprises a router in a defined collection of routers.

20. The computer program of claim 19, wherein the defined collection of routers comprise routers within an autonomous system.

21. The computer program of claim 20, wherein the defined collection of routers within an autonomous system comprise routers within an OSPF (Open Short Path First) system.

22. The computer program of claim 19, wherein the defined collection of network nodes comprises routers in more than one autonomous system.

23. The computer program of claim 19, wherein the instructions for causing a processor to send the received network layer address of the node and a network layer address of the first router toward a second router comprise instructions for causing a processor to initiate flooding of the defined collection of routers with the received network layer address of the node and the network layer address of the first router.

24. The computer program of claim 18, wherein the network layer address of the node comprises an Internet Protocol address.

25. The computer program of claim 18, wherein the node comprises a wireless node.

26. The computer program of claim 18, wherein sending the received network layer address of the node and the network layer address of the first router toward a second router comprises sending without tunneling.

13. A method for use in delivering network messages, the method comprising:

flooding a collection of routers with information identifying mobile nodes served by the routers, the information for each mobile node associating a network layer address of the mobile node with a network layer address of the agent router;

tunneling messages addressed to one of the mobile nodes to the associated agent router;

de-tunneling messages at the agent router; and

sending the de-tunneled message toward the mobile node.

18. A computer program product, disposed on a computer readable medium, for use in delivering network messages, the computer program including instructions for causing a processor to:

(a) receive at a first router a network layer address of a node, the first router and the node both being on a sub-network that is topologically foreign with respect to the network layer address of the node;

(b) send from the first router the received network layer address of the node and a network layer address of the first router toward a second router, the second router being on a sub-network that is topologically foreign with respect to the network layer address of the node;

(c) receive at the first router a message tunneled toward the first router by the second router in response to receiving a message at the second router having a destination address of the node;

(d) de-tunnel the tunneled message; and

(e) send the de-tunneled message toward the node;

wherein (a)-(e) proceed without requiring communication with any node on a sub-network that is a topologically home sub-network with respect to the network layer address of the node