Abstract: A router line card is partitioned to separate the packet forwarding functions from physical port interfacing. For each packet forwarding card, at least one redundant port interface is provided. Identical input packets are transmitted via these redundant input port interfaces, one of which is eventually selected based on, for example, SONET standard criteria. If there is a failure, the router selects the interface path that is operating properly and rejects the path containing a failed element. Thus, the router decides locally how to correct the problem internally. Moreover, following an equipment failure the now offline failed interface path can be replaced, while the equipment remains in service using the duplicated interface path. The system can be restored to full duplex operation without affecting the existing traffic, providing for a hot replacement of a failed path. Because the interfaces are separate, a failed module can be renewed and replaced while the equipment is in service.

Abstract: A router rolls back a current running configuration to a selected prior running configuration without requiring interruption or reinitialization of the router or of its network connections. The router retrieves command line interface control settings associated with the selected prior running configuration and those associated with the current running configuration. The router then generates and executes a rollback script based on the difference between the prior control settings and the current control settings.