High-availability packet forwarding apparatus and method
View Patent ↗Failover protection is provided on the same facilities for a network connection passing through a high-availability router having shared resources managed by two control processors that respectively maintain a forwarding information bases (FIB). The two processors run asynchronously in a master/standby relationship. Integrity of processes running on the control processors is monitored and a forwarding engine forwards packets according to a FIB maintained by an in-service one of the control processors. If one of the control processors fails, the other control processor uses the same bandwidth on the same facility to continue forwarding packets for a network connection. Identifiers in each packet associated with the network connection are used to indicate the reserved bandwidth associated with the network connection.
1. An apparatus for providing high-availability packet forwarding, with protection paths over the same facility without reserving duplicate bandwidth for the protection path, comprising:
a service termination card having a packet forwarding engine for receiving and forwarding packets in accordance with a forwarding information base;
a first control processor running a plurality of processes and communicatively coupled to the service termination card, the first control processor being designated master of a routed interface for a network connection and allocated bandwidth for the network connection;
a second control processor running, asynchronously with respect to the first control processor, a plurality of processes and communicatively coupled to the service termination card, the second control processor being designated master of a backup routed interface for the network connection and allocated the same bandwidth for the network connection;
a first forwarding information base (FIB) on the service termination card having forwarding information maintained by the first control processor;
a second forwarding information base on the service termination card having forwarding information maintained by the second control processor;
means for the packet forwarding engine to forward packets associated with the network connection in accordance with the first forwarding information base unless an integrity of the processes running on the first control processor is lost, and for forwarding the packets associated with the network connection using the second forwarding information base and the same bandwidth if an integrity of processes running on the first control processor is lost;
means for identifying the allocated bandwidth associated with the connection, using an identifier of the network connection carried in a predetermined field of packets being conveyed over the network connection, if the primary interface becomes unavailable; and
a forwarding information base (FIB) manager that receives FIB information from the first and second control processors and stores the FIB information in a memory of the service termination card;
wherein the FIB manager stores primary and backup label switched paths (LSPs) in each of the first and second FIBs so that the primary LSPs in the first FIB are created and maintained by the first control processor and the backup LSPs in the first FIB are created and maintained by the second control processor, while the FIB manager stores the primary and secondary LSPs in a reverse order in the second FIB, to provide line protection as well as control processor fault protection for label switched paths.
2. The apparatus as claimed in claim 1 wherein the first and second forwarding information bases on the service termination card respectively comprise an Internet protocol forwarding information base.
3. The apparatus as claimed in claim 1 wherein the first and second forwarding information bases on the service termination card respectively comprise a multi-protocol label switching forwarding information base.
4. The apparatus as claimed in claim 1 further comprising a bandwidth manager for controlling reservation of local input/output bandwidth between the first and second control processors, the bandwidth manager being adapted to release bandwidth assigned to the network connection on a loss of integrity in the first control processor, and to re-assign the bandwidth to the second control processor when the second forwarding information base is used to forward the packets associated with the network connection.
5. The apparatus as claimed in claim 4 wherein the bandwidth manager is communicatively connected to a heart beat monitor that monitors an integrity of process running on the first and second control processes, and informs the bandwidth manager if one of the control processors is declared out-of service.
6. An apparatus for providing high-availability packet forwarding, with protection paths over the same facility without reserving duplicate bandwidth for the protection path, comprising:
a service termination card having a packet forwarding engine for receiving and forwarding packets in accordance with a forwarding information base;
a first control processor running a plurality of processes and communicatively coupled to the service termination card, the first control processor being designated master of a routed interface for a network connection and allocated bandwidth for the network connection;
a second control processor running, asynchronously with respect to the first control processor, a plurality of processes and communicatively coupled to the service termination card, the second control processor being designated master of a backup routed interface for the network connection and allocated the same bandwidth for the network connection;
a first forwarding information base (FIB) on the service termination card having forwarding information maintained by the first control processor;
a second forwarding information base on the service termination card having forwarding information maintained by the second control processor;
means for the packet forwarding engine to forward packets associated with the network connection in accordance with the first forwarding information base unless an integrity of the processes running on the first control processor is lost, and for forwarding the packets associated with the network connection using the second forwarding information base and the same bandwidth if an integrity of processes running on the first control processor is lost; and
means for identifying the allocated bandwidth associated with the connection, using an identifier of the network connection carried in a predetermined field of packets being conveyed over the network connection, if the primary interface becomes unavailable;
wherein the first and second control processors are respectively adapted to advertise all local interfaces, so that reachability is maintained in a core network in an event that one of the control processors loses integrity.