Compact load balanced switching structures for packet based communication networks

Abstract

A switching node is disclosed for the routing of packetized data employing a multi-stage packet based routing fabric combined with a plurality of memory switches employing memory queues. The switching node allowing reduced throughput delays, dynamic provisioning of bandwidth and packet prioritization.

1 . A switching node comprising:
 a plurality of input ports for receiving data packets;   a plurality of output ports for providing output data from the switching node;   a switching fabric for routing the data packets received over the plurality of input ports to the plurality of output ports as output data, wherein the switching fabric routes a first packet flow of first data packets, received at a first input port and destined for a first output port, into a plurality of packet subflows through the switching fabric, wherein the first data packets of the first packet flow have a first packet flow sequence, wherein the switching fabric routes each first data packet into each packet subflow of the plurality of packet subflows according to a distribution sequence; and   at least one memory switch comprising a plurality of memory queues coupled for storing of packet data therein, for each packet subflow:
 the switching fabric routing to a respective memory queue for temporary storage, first data packets which have been routed into the packet subflow and other data packets comprising:
 data packets received over at least one other input port different from the first input port; and 
 data packets destined for at least one other output port different from the first output port, 
 
   the switching fabric routing the first data packets of other packet subflows different from the packet subflow away from the respective memory queue,   
       wherein the switching fabric combines first data packets of each packet subflow, after temporary storage within the at least one memory switch, with use of the distribution sequence to reconstruct the first packet flow comprising the first data packets in the first packet flow sequence. 
     
     
         2 . A switching node according to  claim 1  wherein the switching fabric routes from the first input port to the first output port each packet of the packet flow through correspondingly similar groups of components each comprising a same number of switches and a same number of memory queues. 
     
     
         3 . A switching node according to  claim 1  wherein for each packet subflow the switching fabric routes said other data packets to the respective memory queue for temporary storage with said first data packets which have been routed into the packet subflow to provide load balancing within the switching node. 
     
     
         4 . A switching node comprising:
 a plurality of input ports for receiving data packets;   a plurality of output ports for providing output data from the switching node;   a switching fabric for routing data packets received over the plurality of input ports to the plurality of output ports as output data, wherein the switching fabric routes for each input port-output port pair:
 a respective packet flow of data packets, received at the input port of the pair and destined for the output port of the pair, into a respective plurality of packet subflows through the switching fabric, wherein the data packets of the respective packet flow have a respective packet flow sequence, wherein the switching fabric routes each data packet of the respective packet flow into each packet subflow of the respective plurality of packet subflows of the respective packet flow according to a respective distribution sequence; and 
   at least one memory switch comprising a plurality of memory queues coupled for storing of packet data therein, for each respective packet flow:
 the switching fabric, for each respective packet subflow of the respective plurality of packet subflows, routing to a respective memory queue for temporary storage:
 the data packets of the respective packet flow which have been routed into the packet subflow and other data packets comprising:
 data packets received over at least one other input port different from the input port of the pair for which the switching fabric routes the respective packet flow; and 
 data packets destined for at least one other output port different from the output port of the pair for which the switching fabric routes the respective packet flow, 
 
 the switching fabric routing the data packets of other packet subflows of the respective plurality of packet subflows which are other than the packet subflow of the respective packet subflow away from the respective memory queue, 
 
   
       wherein, for each pair, the switching fabric combines data packets of each packet subflow of the respective plurality of packet subflows, after temporary storage within the at least one memory switch, with use of the respective distribution sequence to reconstruct the respective packet flow comprising the data packets in the respective packet flow sequence. 
     
     
         5 . A switching node according to  claim 4  wherein for each respective packet subflow the switching fabric routes said other data packets to the respective memory queue for temporary storage with said first data packets which have been routed into the respective packet subflow to provide load balancing within the switching node.