Use of alternate paths in forwarding of network packets

摘要

In non-minimal routing, a switch determines outgoing links for preferred paths (e.g. shortest paths). Then, for another node in a preferred path, the switch determines outgoing links for paths to that node in a modified network in which each link in a previously determined path to the node is cut off. Packets can be tunneled on non-preferred paths to that node. Other features and embodiments are also provided.

主权项

1. A method for operating a first switch, the method comprising obtaining in a computer storage, by the first switch, a forwarding database for use in packet forwarding, wherein obtaining the forwarding database comprises the first switch performing operations of:
determining one or more first outgoing links for one or more shortest paths to a first destination; for at least one shortest path to the first destination, selecting a second switch in the shortest path; determining one or more second outgoing links for one or more non-minimal paths to the second switch based on one or more predefined restrictions which allow a non-minimal path to the second switch to pass through a switch which is farther from the first destination than is the first switch; storing forwarding data in the computer storage in the forwarding database, the forwarding data specifying the first and second outgoing links as alternate links available to forward packets to the first destination.