Granted Patent B2

US 8,769,154 · App. 10/350,817 · Granted Jul 1, 2014

Abstract

Claims (39)

1. A method for facilitating routing protocol redundancy in a network element, comprising:

adding an additional routing module to the network element, wherein the network element includes an existing routing module having an existing collection of routing protocol information associated therewith; and

synchronizing a higher layer protocol task of the additional routing module with a higher layer protocol task of the existing routing module in response to adding the additional routing module, wherein the additional routing module performs a lower layer protocol task of the additional routing module and the existing routing module performs a lower layer protocol task of the existing routing module, wherein the lower layer protocol task of the additional routing module is of a lower layer than the higher layer protocol task of the additional routing module and the lower layer protocol task of the existing routing module is of a lower layer than the higher layer protocol task of the existing routing module; and

maintaining the higher layer protocol task of the additional routing module at least one higher layer protocol packet behind the higher layer protocol task of the existing routing module such that the higher layer protocol task of the additional routing module processes a particular higher layer protocol packet after the existing routing module processes the particular higher layer protocol packet.

2. The method of claim 1 wherein synchronizing the higher layer protocol task of the additional routing module with the higher layer protocol task of the existing routing module includes:

imparting the existing collection of routing protocol information upon the additional routing module in response to adding the additional routing module to the network element;

updating the existing routing module with new routing protocol information; and

updating the additional routing module with the new routing protocol information.

3. The method of claim 2 wherein:

updating the additional routing module with the new routing protocol information is performed after a higher layer protocol task of the existing routing module processes the new routing protocol information; and

the new routing protocol information is a higher layer protocol packet.

4. The method of claim 3 wherein:

the higher layer protocol packet specifies a route to advertise; and

processing the higher layer protocol packet includes advertising the route.

5. The method of claim 2 , further comprising:

forwarding at least a portion of the new routing protocol information to the additional routing module;

processing the at least the portion of the new routing protocol information by the higher layer protocol task of the additional routing module; and

acknowledging receipt of the at least the portion of the new routing protocol information, wherein the step of forwarding the at least the portion of the new routing protocol information to the additional routing module and the step of processing the at least the portion of the new routing protocol information by the additional routing module occur prior to the step of acknowledging receipt of the at least the portion of the new routing protocol information.

6. The method of claim 2 wherein the new routing protocol information includes at least one of a BGP message, TCP task-related state information, BGP routing tables and route state information.

7. The method of claim 2 wherein updating the additional routing module with the new routing protocol information comprises:

updating an advertised route on the additional routing module only after the existing routing module has advertised the advertised route.

8. The method of claim 1 wherein the existing collection of routing protocol information includes at least one of BGP message, TCP task-related state information, BGP routing tables and route state information.

9. The method of claim 1 wherein adding the additional routing module includes adding the additional routing module after the existing routing module has been in operation for a period of time and wherein at least a portion of the routing protocol information was dynamically established over the period of time.

10. The method of claim 1 further comprising:

identifying a peer network element from which an offending inbound higher layer protocol packet was received; and

re-establishing a higher layer protocol task session with the peer network element after the synchronizing the higher layer protocol task of the additional routing module with the higher layer protocol task of the existing routing module is performed.

11. Apparatus for facilitating routing protocol redundancy in a network element, comprising:

an existing routing module having an existing collection of routing protocol information associated therewith; and

an additional routing module coupled to the existing routing module, wherein a higher layer protocol task of the additional routing module is synchronized with a higher layer protocol task of the existing routing module in response to coupling the additional routing module to the existing routing module, wherein the additional routing module causes a received packet to remain unprocessed by the higher layer protocol task of the additional routing module until the received packet is determined to be non-offensive by the higher layer protocol task of the existing routing module, wherein the additional routing module performs a lower layer protocol task of the additional routing module and the existing routing module performs a lower layer protocol task of the existing routing module, wherein the lower layer protocol task of the additional routing module is of a lower layer than the higher layer protocol task of the additional routing module and the lower layer protocol task of the existing routing module is of a lower layer than the higher layer protocol task of the existing routing module.

12. The apparatus of claim 11 wherein synchronization of the higher layer protocol task of the additional routing module with the higher layer protocol task of the existing routing module includes imparting the existing collection of routing protocol information upon the additional routing module in response to adding the additional routing module to the network element, updating the existing routing module with the new routing protocol information, and updating the additional routing module with the new routing protocol information.

13. The apparatus of claim 12 wherein updating of the additional routing module with the new routing protocol information is performed after a higher layer protocol task of the existing routing module processes the new routing protocol information and wherein the new routing protocol information is a higher layer protocol packet.

14. The apparatus of claim 13 wherein the higher layer protocol packet specifies a route to advertise and processing the higher layer protocol packet includes advertising the route.

15. The apparatus of claim 12 wherein the existing routing module forwards at least a portion of the new routing protocol information to the additional routing module and the higher layer protocol task of the additional routing module processes the at least the portion of the new routing protocol information prior to acknowledging receipt of the at least the portion of the new routing protocol information.

16. The apparatus of claim 12 wherein the new routing protocol information includes at least one of a BGP message, TCP task-related state information, BGP routing tables and route state information.

17. The apparatus of claim 12 wherein updating the additional routing module with the new routing protocol information comprises:

updating an advertised route on the additional routing module only after the existing routing module has advertised the advertised route.

18. The apparatus of claim 11 wherein the existing collection of routing protocol information includes at least one of BGP message, TCP task-related state information, BGP routing tables and route state information.

19. The apparatus of claim 11 wherein the additional routing module is added after the existing routing module has been in operation for a period of time and wherein at least a portion of the routing protocol information was dynamically established over the period of time.

20. The apparatus of claim 11 wherein the existing routing module identifies a peer network element from which an offending inbound higher layer protocol packet was received and re-establishes a higher layer protocol task session with the peer network element after the higher layer protocol task of the additional routing module is synchronized with the higher layer protocol task of the existing routing module.

Assignments (11)