Priority-based arbitration for parallel multicast routing with self-directed data packets

Abstract

A parallel multicast star topology data network includes a plurality of input buffers, a first arbitration mechanism coupled to the plurality of input buffers, a plurality of output buffers coupled to the first arbitration mechanism and a plurality of interconnect exits coupled to the plurality of output buffers. When packet contents of a multicast message are ready for release from the first arbitration mechanism then all of the packet contents are substantially simultaneously released to the plurality of output buffers and then substantially simultaneously to the plurality of interconnect exits.

What is claimed is: 
     
         1 . A method, comprising:
 operating a parallel multicast star topology data network including
 a plurality of input buffers, 
 a first arbitration mechanism coupled to the plurality of input buffers, 
 a plurality of output buffers coupled to the first arbitration mechanism and 
 a plurality of interconnect exits coupled to the plurality of output buffers, 
   releasing substantially simultaneously all packet contents of a multicast message to the plurality of output buffers when all packet contents are ready for release from the first arbitration mechanism; and then   releasing substantially simultaneously all packet contents of the multicast message from the plurality of output buffers to the plurality of interconnect exits.   
     
     
         2 . The method of  claim 1 , further comprising a second arbitration mechanism coupled to the first arbitration mechanism, wherein the parallel multicast star topology data network supports at least two priorities. 
     
     
         3 . The method of  claim 2 , further comprising a third arbitration mechanism coupled to both the first arbitration mechanism and the second arbitration mechanism, wherein the parallel multicast star topology data network supports at least three priorities. 
     
     
         4 . The method of  claim 1 , wherein releasing substantially simultaneously all packet contents of a multicast message to the plurality of output buffers includes coordinating using the arbitration mechanism when all packet contents are ready for release. 
     
     
         5 . The method of  claim 1 , wherein coordinating using the arbitration mechanism when all packet contents are ready for release includes cascaded scanning with linked scans operating in parallel. 
     
     
         6 . The method of  claim 1 , further comprising treating a unicast message on an equal and unbiased basis compared to the multicast message. 
     
     
         7 . An apparatus, comprising:
 a parallel multicast star topology data network including
 a plurality of input buffers, 
 a first arbitration mechanism coupled to the plurality of input buffers, 
 a plurality of output buffers coupled to the first arbitration mechanism and 
 a plurality of interconnect exits coupled to the plurality of output buffers, 
   wherein when packet contents of a multicast message are ready for release from the first arbitration mechanism then all of the packet contents are substantially simultaneously released to the plurality of output buffers and then substantially simultaneously to the plurality of interconnect exits.   
     
     
         8 . The apparatus of  claim 7 , further comprising a second arbitration mechanism coupled to the first arbitration mechanism, wherein the parallel multicast star topology data network supports at least two priorities. 
     
     
         9 . The apparatus of  claim 8 , further comprising a third arbitration mechanism coupled to both the first arbitration mechanism and the second arbitration mechanism, wherein the parallel multicast star topology data network supports at least three priorities. 
     
     
         10 . The apparatus of  claim 7 , wherein each of the plurality of input buffers includes a first in first out buffer. 
     
     
         11 . The apparatus of  claim 7 , wherein each of the plurality of output buffers includes a first in first out buffer.