Packet switch employing dynamic transfer of data packet from central shared queue path to cross-point switching matrix path

A system for forwarding a data packet within a packet switch having an input port, an output port, and a bypass path and a central queue path coupled in parallel between the input port and the output port, said system comprising:

• means for dividing the data packet into a sequence of multiple portions;
• means for forwarding the sequence of multiple portions from the input port to the output port through the central queue path;
• means for determining that one portion of the multiple portions comprises a critical portion;
• and
• means for switching forwarding of the sequence of multiple portions from the input port to the output port to the bypass path responsive to said means for determining ascertaining that said one portion of the multiple portions comprises a critical portion, said switching resulting in passing said critical portion from said input port to said output port through the bypass path irrespective of whether contention exists for said output port.

A packet switch comprising:

• multiple input ports and multiple output ports;
• a central queue path coupling said multiple input ports to said multiple output ports;
• a bypass path comprising a cross-point switching matrix coupling said multiple input ports to said multiple output ports, wherein said bypass path and said central queue path are coupled in parallel between said multiple input ports and said multiple output ports;
• and
• data packet flow control circuitry coupled to said multiple input ports and said multiple output ports for controlling transfer of a data packet from at least one input port of said multiple input ports to at least one output port of said multiple output ports, said data packet control circuitry being adapted to forward a sequence of multiple portions of the data packet from said at least one input port to said at least one output port through the central queue path, and to identify during said forwarding a next portion of said multiple portions of said sequence as a critical portion to said at least one output port, and in response thereto, to switch forwarding of the sequence of multiple portions of the data packet from the central queue path to the bypass path so that the critical portion is passed directly from the at least one input port to the at least one output port through the bypass path irrespective of whether contention exists for the at least one output port.

An article of manufacture comprising:

• a computer program product comprising computer usable medium having computer readable program code means therein for use in forwarding a data packet within a packet switch having an input port, an output port, and a bypass path and a central queue path coupled in parallel to the input port and the output port, said computer readable program code means in said computer program product comprising:
• computer readable program code means for causing a computer to effect dividing the data packet into a sequence of multiple portions;
• readable program code means for causing a computer to effect forwarding the sequence of multiple portions from the input port to the output port through the central queue path;
• computer readable program code means for causing a computer to effect determining during said forwarding that one portion of the multiple portions of the sequence comprises a critical portion;
• and
• computer readable program code means for causing a computer to effect switching forwarding of the sequence of multiple portions from the input port to the output port through the bypass path when said determining determines that said one portion of the multiple portions of the sequence comprises a critical path, said switching resulting in passing said critical portion from said input port to said output port through the bypass path irrespective of whether contention exists for said output port.