Patent ID: 7292535
Filing Date: 2007-11-06
Classification: H04L

Abstract:
1. A method of a highly-available Open Shortest Path First (OSFP) routing network, comprising the steps of: using an active OSPF instance in an active processor and a backup OSPF instance in a backup processor synchronizing the dynamic state of the backup OSPF instance with the dynamic state of the active OSPF instance using explicit message transmission from said active instance to said backup instance; maintaining dynamic state synchronization of said backup OSPF instance with said active OSPF instance using a combination of explicit message update from said active OSPF instance to said backup OSPF instance together with a message flow-through mechanism comprising reading by said backup OSPF instance every one of a plurality of OSPF protocol packets before said every one of the plurality of OSPF protocol packets being read by the active instance; OSPF protocol packet being read by said active OSPF instance sent to a router; in the event of fail-over of said active OSPF instance, seamlessly recovering form said fail-over without reconfiguring or interrupting the traffic among peer router in said network, by functionally substituting the state synchronized backup OSPF instance for said active OSPF instance, and establishing said backup OSPF instance as a new active OSPF instance.