Patent ID: 6778539
Filing Date: 2004-08-17
Classification: H04L

Abstract:
A method of routing a data cell through a hierarchy of routers arranged into a top-topology and one or more sub-topologies, the method comprising:receiving a data cell at a first router, wherein: the data cell includes a destination ID; the first router has a router ID; and each of the destination ID and the router ID comprises a first portion and a second portion; comparing a topology portion of the destination ID to a corresponding topology portion of the router ID, wherein: said topology portion of the router ID is configured to identify a topology of routers in which the first router is located; and the topology is either a top-topology of routers or one of multiple sub-topologies of routers hierarchically depending from the top-topology; if said topology portion of the destination ID does not match said topology portion of the router ID: reading a control register in the first router to identify a top output port of the first router configured to couple the first router to the top-topology; and forwarding the data cell on the top output port; and if said topology portion of the destination ID matches said topology portion of the router ID: selecting one of the first portion and the second portion of the destination ID, wherein the other of the first portion and the second portion of the destination ID comprises said topology portion of the destination ID; using said selected portion of the destination ID to lookup in a routing table a first output port for forwarding the data cell toward a node having the destination ID; and forwarding the data cell on the first output port.