System and method for router connection protection switching

摘要

If an active router Master Control Processor (11) fails, a backup Master Control Processor (12) switches over without interrupting peer network router connections, because all previously established connection parameters are replicated on both Master Control Processors. Once the Master Control Processor programs line cards (31), the packet forwarding modules (501) and embedded system function without further involvement of the Master Control Processor until the next programming update. Messages flow through the backup Master Control Processor and then through the active Master Control Processor, which outputs messages through the backup Master Control Processor. Thus the backup Master Control Processor captures state changes before and after the active Master Control Processor. Both Master Control Processors maintain replicated queues in which they store replicated messages awaiting processing or retransmission. If acknowledgment of receiving a transmitted message is received from a destination peer router, that message is deleted from both Master Control Processors. If acknowledgment is not received within a predetermined interval, the stored message is retransmitted. Message splicing prevents lost and partially transmitted messages during and after switchovers.