Splitting and sharing routing information among several routers acting as a single border router

• US 9,160,654 B2
• Filed: 01/09/2013
• Issued: 10/13/2015
• Est. Priority Date: 08/22/2002
• Status: Expired due to Fees

• Current Assignee: Kyndryl Incorporated
• Original Assignee: International Business Machines Corporation
• Inventors: Dispensa, Jean-Claude, Lund, Amaud
• Primary Examiner(s): Lee, Andrew
• Application Number:
  US13/737,357
• Publication Number:
  US 20130121339A1
• Time in Patent Office: 1,007 Days
• Field of Search: 370/392, 370/400, 370/401, 370/410
• US Class Current: 1/1
• CPC Class Codes: H04L 12/1868 Measures taken after transmission, e.g. acknowledgments
• CPC Class Codes: H04L 45/34 Source routing
• CPC Class Codes: H04L 45/44 Distributed routing

Abstract

Routers split and share routing information among several routers within a group of routers acting as a single border router in an Internet protocol (IP) network, each router comprising a routing table. A router of the group selects routes in the routing table of the router; requests other routers of the group to replace, in their routing tables, each selected route with the router as next hop; associates parts of-non selected routes, each one with another router of the group; and removes and replaces, in the routing table, each-non selected route associated with a router of the group by the associated router as next hop.

Claims

1. A computer system router, comprising:

a hardware memory device comprising a first routing table stored thereon;

wherein the router acts as a single border router in communication with a group of other routers in an internet protocol network; and

wherein the router;

compares a size of the first routing table to a predefined threshold;

splits the first routing table into a plurality of subnetworks in response to the size of the first routing table exceeding the predefined threshold; and

takes responsibility for routing internet protocol network traffic intended for another subnetwork split from a second routing table of another router of the group of other routers by informing each of the other routers that it is ready to receive internet protocol network traffic from the each of the other routers that is directed to the another subnetwork, and that each of the other routers should select and remove from their own routing tables a route related to the another subnetwork and replace the removed route by a single route pointing to the router.

2. The computer system router according to claim 1, wherein the router further forwards internet protocol network traffic corresponding to a non-selected route to a router of the group of routers that is associated with said non-selected route within the first routing table.

3. The computer system router according to claim 1, wherein the router further receives from at least one of the other routers internet protocol traffic corresponding to the selected and removed route and routs said received internet protocol traffic corresponding to the selected and removed route.

4. The computer system router according to claim 1, wherein the router further selects routes in the first routing table by selecting contiguous internet protocol addresses within a given address range.

5. The computer system router according to claim 1, wherein the router further establishes sessions with the other routers of the group and creates a list of routers of the group.

6. The computer system router according to claim 5, wherein each of the group of other routers is a border router.

7. The computer system router according to claim 6, wherein the router further exchanges routing information with each of the other group of routers using a border gateway protocol.

8. A computer program product, comprising:

a hardware memory device comprising instructions stored thereon for execution on a first router that cause the first router to act as a single border router in communication with a group of other routers in an internet protocol network, by;

comparing a size of a first routing table of the first router to a predefined threshold;

splitting the first routing table into a plurality of subnetworks in response to the size of the first routing table exceeding the predefined threshold; and

taking responsibility for routing internet protocol network traffic intended for another subnetwork split from a second routing table of another router of the group of other routers by informing each of the other routers that it is ready to receive internet protocol network traffic from the each of the other routers that is directed to the another subnetwork, and that each of the other routers should select and remove from their own routing tables a route related to the another subnetwork and replace the removed route by a single route pointing to the first router.

9. The computer program product according to claim 8, wherein the instructions for execution on the first router, further cause the first router to forward internet protocol network traffic corresponding to a non-selected route to a router of the group of routers that is associated with said non-selected route within the first routing table.

10. The computer program product according to claim 8, wherein the instructions for execution on the first router, further cause the first router to receive from at least one of the other routers internet protocol traffic corresponding to the selected and removed route, and rout said received internet protocol traffic corresponding to the selected and removed route.

11. The computer program product according to claim 8, wherein the instructions for execution on the first router, further cause the first router to select routes in the first routing table by selecting contiguous internet protocol addresses within a given address range.

12. The computer program product according to claim 8, wherein the instructions for execution on the first router, further cause the first router to establish sessions with the other routers of the group and create a list of routers of the group.

13. The computer program product according to claim 12, wherein each of the group of other routers is a border router.

14. The computer program product according to claim 13, wherein the instructions for execution on the first router, further cause the first router to exchange routing information with each of the other group of routers using a border gateway protocol.