Method and system for improving bandwidth and reducing idles in fibre channel switches

A fibre channel switch element for routing fibre channel frames, comprising:

• a receive segment in a fibre channel port of the fibre channel switch element for receiving the fibre channel frames and a transmit segment that transmits the received fibre channel frames;
• wherein the transmit segment of the fibre channel port requests an early frame transfer of a fibre channel frame from a memory location of the receive segment of the fibre channel port to the transmit segment, before the transmit segment completes a status check;
• and in response to the earl;
• frame transfer request, the receive segment activates an early frame transfer;
• and
• wherein, after completing the status check, the transmit segment determines if there is a need for aborting the early frame transfer request;
• generates a request abort command to abort the early frame transfer request if there is a need for aborting the early frame transfer request and sends the request abort command to the receive segment;
• and
• wherein after the early frame transfer request is aborted, another frame from a different source port is selected while the receive segment continues to have the memory location available for the transmit segment to re-request the frame transfer from the same memory location.

A switch element, comprising:

• a receive segment of a port for receiving a frame;
• and
• a transmit segment of the port for transmitting a frame;
• and
• before the transmit segment completes a status check;
• the transmit segment sends a request for an early frame transfer to the receive segment to transfer the frame from a memory location of the receive segment to the transmit segment;
• and in response to the early frame transfer request, the receive segment activates an early frame transfer;
• wherein, after completing the status check, the transmit segment determines if there is a need for aborting the early frame transfer request;
• and if there is a need, generates a request to abort the early frame transfer request and sends the request to the receive segment so that the early frame transfer is aborted;
• and
• wherein after the early frame transfer is aborted the receive segment continues to have the memory location available for the transmit segment to re-request the frame transfer from the same memory location.

A method for a switch element having a plurality of ports, each port having a receive segment for receiving frames and a transmit segment for transmitting frames;

• comprising:
• a. before the transmit segment completes a status check, requesting an early frame transfer of a frame from a memory location of the receive segment of a port to the transmit segment of the port;
• wherein the transmit segment sends a request to the receive segment for the early frame transfer;
• b. activating an early frame transfer;
• wherein the early frame transfer is activated at the receive segment;
• c. after completing the status check, determining if there is a need for aborting
• the early frame transfer request sent to the receive segment in step (a);
• wherein the transmit segment determines if there is a need for aborting the early frame transfer request and if there is a need, generates a request-abort command to abort the early frame transfer request and sends the request abort command to the receive segment;
• and
• (d) after aborting the early frame transfer, selecting another frame while continuing to have the memory location in step (a) available for the transmit segment to re-request transfer of the frame from the same memory location of step (a).