Nishit M Vasavada

US Patent:

20040078619, Apr 22, 2004

Filed:

Jun 27, 2002

Appl. No.:

10/183272

Inventors:

Nishit Vasavada - Fremont CA, US

International Classification:

G06F011/00

US Classification:

714/004000

Abstract:

The present invention relates to a method and system for implementing link level protocol redundancy in a router. In particular, the invention relates to providing redundancy of the Intermediate System Intra-domain Routing Information Exchange Protocol (IS-IS) routing protocol. An active processor provides IS-IS operations. In the present invention, a standby processor is coupled to the active processor. During the initial synchronization, all protocol information from the active processor is forwarded to the standby processor. The protocol information can include IS-IS global protocol information, IS-IS configuration information, IS-IS adjacencies information, IS-IS interface information and link state packet information. Thereafter, any updates of protocol information are immediately forwarded to the standby processor in an orderly and controlled manner. Upon failure of the active processor, the router is switched to the standby processor and all IS-IS protocol operations are performed on what used to be the standby processor.