DETERMINING AN OPTIMAL ROUTE ADVERTISEMENT IN A REACTIVE ROUTING ENVIRONMENT

• US 20090141651A1
• Filed: 12/03/2007
• Published: 06/04/2009
• Est. Priority Date: 12/03/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: White, Russell I., Retana, Alvaro Enrique, Moore, Steven Edward, Ng, James L.
• Granted Patent: US 8,121,130 B2
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00
• 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 45/02 Topology update or discovery

Abstract

In an example embodiment, a method is provided. In this method, a network address query is received. A first network address of a known apparatus is retrieved from a routing table, in response to the network address query. A second network address may be determined based upon the network address query, the second network address having a smaller bit length than the first network address. An aggregate value may be advertised that represents a range of reachable network addresses, the range of reachable network addresses including the second network address.

Claims

1. A method comprising:

receiving a network address query;

retrieving a first network address of a known apparatus from a routing table, in response to the network address query;

determining a second network address based upon the network address query, the second network address having a smaller bit length than the first network address; and

advertising an aggregate value that represents a range of reachable network addresses, the range of reachable network addresses including the second network address.

2. The method of claim 1, wherein the determining of the second network address comprises performing a recursive operation on the first network address.

3. The method of claim 1, wherein the determining of the second network address is based upon a minimal coverage value.

4. The method of claim 1, further comprising receiving a response from an apparatus, the response confirming a path to another apparatus based upon the second network address.

5. The method of claim 1, wherein the aggregate value is a smaller a bit length than the network query address query.

6. The method of claim 1, further comprising installing the aggregate value into the routing table.

7. A method comprising:

receiving an aggregate value, with a prefix, that represents a range of reachable network addresses;

comparing the prefix of the aggregate value to a prefix of a network address query, the comparing being based upon a logical operation; and

generating a network address value, where the prefix of the network address query and the prefix of the aggregate value are equal.

8. The method of claim 7, wherein the generating of the network address value is based upon a minimal coverage value.

9. The method of claim 7, wherein the generating of the network address value comprises finding an address value that lies between the aggregate value and the network address query.

10. The method of claim 7, further comprising installing the aggregate value into a routing table that is associated with an apparatus.

11. An apparatus comprising:

a first receiver to receive a network address query;

a retriever to receive a first network address of a known apparatus from a routing table, in response to the network address query;

a first calculation engine to determine a second network address based upon the network address query, the second network address having a smaller bit length than the first network address; and

an advertising engine to advertise an aggregate value that represents a range of reachable network addresses, the range of reachable network addresses including the second network address.

12. The apparatus of claim 11, wherein the first calculation engine determines the second network address by a recursive operation performed on the first network address.

13. The apparatus of claim 11, wherein the first calculation engine determines the second network address based upon a minimal coverage value.

14. The apparatus of claim 11, further comprising a second receiver to receive a response from a further apparatus, the response confirming a path to another apparatus based upon the second network address.

15. The apparatus of claim 11, wherein the aggregate value is a smaller bit length than the network query address query.

16. The apparatus of claim 11, further comprising an insertion engine to install the aggregate value into the routing table.

17. An apparatus comprising:

a receiver to receive an aggregate value, with a prefix, that represents a range of reachable network addresses;

a comparison engine to compare the prefix of the aggregate value to a prefix of a network address query, the comparing being based upon a logical operation; and

an address generator to generate a network address value, where the prefix of the network address query and the prefix of the aggregate value are equal.

18. The apparatus of claim 17, wherein the address generator generates the network address value based upon a minimal coverage value.

19. The apparatus of claim 17, wherein the address generator generates the network address value by finding an address value that lies between the aggregate value and the network address query.

20. The apparatus of claim 17, further comprising an insertion engine to install the aggregate value into a routing table that is associated with the apparatus.

21. An apparatus comprising:

means for receiving a network address query;

means for retrieving a first network address of a known apparatus from a routing table, in response to the network address query;

means for determining a second network address based upon the network address query, the second network address having a smaller bit length than the first network address; and

means for advertising an aggregate value that represents a range of reachable network addresses, the range of reachable network addresses including the second network address.

22. Logic encoded in one or more tangible media for execution and when executed operable to:

receive a network address query;

retrieve a first network address of a known apparatus from a routing table, in response to the network address query;

determine a second network address based upon the network address query, the second network address having a smaller bit length than the first network address; and

advertise an aggregate value that represents a range of reachable network addresses, the range of reachable network addresses including the second network address.