Routing messages between nodes at a foreign sub-network

• US 20020078238A1
• Filed: 12/14/2000
• Published: 06/20/2002
• Est. Priority Date: 09/14/2000
• Status: Abandoned Application

• Current Assignee: BBNT Solutions LLC (Rtx Corporation)
• Original Assignee: BBNT Solutions LLC (Rtx Corporation)
• Inventors: Troxel, Gregory Donald, Gesler, Gwendolyn Jean
• Application Number:
  US09/736,834
• Publication Number:
  US 20020078238A1
• Time in Patent Office: Days
• US Class Current: 709/245
• 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: 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 40/34 Modification of an existing route
• 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]
• CPC Class Codes: H04W 88/005 Data network PoA devices

Abstract

The invention can enable nodes on a foreign sub-network to exchange messages. After receiving a network layer address of a node on a foreign sub-network, a router on the foreign sub-network can deliver messages received from another node on the foreign sub-network to the node without requiring communication with a home agent.

Claims

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

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

(b) attempting to notify a home agent on the first node'"'"'s topological home sub-network of the network layer address of the first node;

(c) receiving at the router a message having a network layer destination address of the first node, the message being received from a second node on the first sub-network;

(d) sending the message toward the first node without sending the message to a different sub-network;

whereby (a)-(d) proceed without requiring receipt of information from the home agent.

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

3. The method of claim 1, wherein the router comprises a foreign agent configured to de-tunnel messages received from the home agent.

4. The method of claim 1, further comprising:

identifying a link layer address of the first node, and

wherein sending the message from the router toward the first node comprises sending the message via the link layer address.

5. The method of claim 1, further comprising:

modifying a routing table to include an entry for the network layer address of the first node.

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

7. The method of claim 1, further comprising:

advertising the availability of the router to the first node.

8. The method of claim 1, wherein attempting to notify comprises determining whether a message can reach the home agent.

9. The method of claim 1, wherein attempting to notify comprises a failed attempt.

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

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

(b) attempt to notify a home agent on the first node'"'"'s topological home sub-network of the network layer address of the first node;

(c) receive at the router a message having a network layer destination address of the first node, the message being received from a second node on the first sub-network;

(d) send the message toward the first node without sending the message to a different sub-network;

whereby (a) - (d) proceed without requiring receipt of information from the home agent.

11. The computer program of claim 10, wherein the network layer address of the first node comprises an Internet Protocol address.

12. The computer program of claim 10, wherein the router comprises a foreign agent configured to detunnel messages received from the home agent.

13. The computer program of claim 10, further comprising instructions for causing the processor to:

identify a link layer address of the first node, and

wherein the instructions for causing the processor to send the message from the router toward the first node comprise instructions for causing the processor to send the message via the link layer address.

14. The computer program of claim 10, further comprising instructions for causing the processor to modify a routing table to include an entry for the network layer address of the first node.

15. The computer program of claim 10, wherein the first node comprises a wireless node.

16. The computer program of claim 10, further comprising instructions for causing the processor to advertise the availability of the router to the first node.

17. The computer program of claim 10, wherein the instructions for causing the processor to attempt to notify comprise instructions for causing the processor to determine whether a message can reach the home agent.

18. A method for use in delivering network messages between mobile nodes on a first sub-network, the first subnetwork being topologically foreign to each of the mobile nodes, the method comprising:

(a) advertising the availability of a foreign agent on the first sub-network;

(b) establishing local bindings between the foreign agent and the mobile nodes, the local bindings associating a network layer address of the mobile nodes with a link layer address of the mobile nodes;

(c) attempting to notify the mobile nodes respective home agents of the mobile nodes attachment to the first sub-network;

(d) receiving at the foreign agent a message from one of the mobile nodes having a network layer destination address of one of the other mobile nodes; and

(e) sending the message to the mobile node having the network layer destination address without sending a message to one of the respective home agents;

whereby (a) - (e) proceed without requiring receipt of information from the respective home agents.