Packet switch modules for computer networks with efficient management of databases used in forwarding of network traffic

摘要

In a packet switch with databases (250, 404) used for packet forwarding, the database pieces are identified by version identifiers (410V) which are used by the packet switch's modules (LCx, RPM0, RPM1) in exchanging information on the databases and requesting updates to the databases. For example, if a primary management module fails and the management is transferred to a secondary management module, the secondary management module requests forwarding modules (e.g. line cards) to identify the database pieces stored on the forwarding modules, and to update the databases as needed. Use of version identifiers reduces the amount of data that has to be transferred in connection with such requests.

主权项

1. A method for operating a packet switch comprising a plurality of modules which comprise a first module and a second module, wherein the packet switch forwards packets in a network according to one or more databases stored on the packet switch, the one or more databases comprising a first database stored on the second module, the first database comprising a set of one or more first pieces stored on the second module, each first piece being identified by an identifier which is a version identifier;
the method comprising performing operations by the first module, the operations comprising: communicating with the second module to request the second module to perform at least one of: (a) inform the first module of information stored in the one or more first pieces stored on the second module, (b) change the set of one or more first pieces stored on the second module; wherein in said communicating, at least one first piece is specified by the first piece's identifier; wherein said communicating with the second module comprises: (1) requesting the second module to perform (a); (2) receiving from the second module a set of one or more identifiers of one or more first pieces stored on the second module; (3) determining from the set of one or more identifiers whether or not the first database is to be updated; (4) if the first database is to be updated, then requesting the second module to perform (b) to update the first database; wherein the set of one or more pieces comprises a baseline piece and one or more incremental pieces, and requesting the second module to perform (b) comprises requesting the second module to aggregate the baseline piece and each said incremental piece into a new baseline piece.