Abstract: A high-speed Fibre Channel switch element in a Fibre Channel network is provided. The Fibre Channel switch element includes, a rate select module that allows a port in the Fibre Channel switch element to operate at a rate equal to and/or higher than 10 gigabits per second (“G”). The port may operate at 20G, 40G or at a rate greater than 40G. Also, a cut status is provided for cut-through routing between ports operating at different speed. Plural transmit and receive lines are used for port operation at a rate equal to or higher than 10G.

Abstract: Method and system for routing fibre channel frames using a fibre channel switch element is provided. The method includes, inserting a time stamp value in a fibre channel frame that is received at a receive segment of the fibre channel switch element; determining if a timeout occurs after a frame arrives at a receive buffer; and processing the frame if the timeout occurred. The method also includes, determining if a delta time value, which provides an accumulated wait time for a frame, is present in frame data; subtracting the delta time stamp value from a global time stamp value and using the resulting time stamp value to determine frame timeout status in the fibre channel switch element. A timeout checker circuit declares a timeout after comparing a time stamp value that is inserted in a fibre channel frame with a programmed time out value and a global counter value.

Abstract: A method and system for routing fibre channel frames using a fibre channel switch element is provided. The switch element includes, a look up table that is indexed by domain, area, a virtual storage area number and/or AL_PA values of frames entering the fibre channel switch element; and logic for generating a column select signal that is used to select a column from the look up table for frame routing information. The switch element also includes logic for validating a frame route by performing word depth match. A register is used to load look up table entries and column entries are selected based on the column select signal. The method includes, indexing a look up table with plural fibre channel frame header values; selecting a table value for routing a fibre channel frame based on a column select signal; and routing the frame if a route is valid.

Abstract: A fibre channel switch element and method for routing fibre channel frames is provided. The switch element includes a receive segment that can add a virtual storage area network (“VSAN”) tagging header to frames that are received by the receive segment; and strip the VSAN tagging header before frames are sent to ports that do not support virtual fabric capability. The receive segment includes a table used for matching fabric extension parameters. An incoming frame's VSAN identity value is compared to a control word entry to generate a value used for routing the incoming frame. The table is used to determine if a frame is part of a virtual fabric. The routing table for each port is used to route frames and the routing table includes entries for supported virtual fabrics.

Abstract: A method and system for distributing credit using a fibre channel switch element is provided. The switch element includes, a wait threshold counter that is used to set up a status for a port that has to wait for certain duration to send a frame due to lack of buffer to buffer credit; a credit module that controls buffer to buffer credit for a transmit segment of the fibre channel switch element; and a virtual lane credit module with a counter that is incremented every time a frame assigned to a virtual lane is sent and decreased every time a VC_RDY is received. The method includes, determining if a VC_RDY primitive is received; and allocating credit to a virtual lane that is not at its maximum credit, after the VC_RDY primitive is received.

Abstract: A method and system for keeping an arbitrated loop open during a frame gap using a fibre channel switch element is provided. The switch element includes a port control module having a receive and transmit segment, wherein the transmit segment activates a timer whose value determines a duration during which the arbitrated loop remains open; determines if a last frame from a sequence of frames from a source port has been transmitted; modifies the timer value if a higher priority frame for transmission is unavailable; and keeps the arbitrated loop open until the timer reaches a certain value. If a higher priority frame is available for transmission before the timer value is modified then the higher priority frame is transmitted and the timer value is re-initialized.

Abstract: A fibre channel switch element for routing fibre channel frame is provided. The switch element includes a fibre channel port that can be configured to support plural data transfer rates. The data transfer rate may be 1 G, 2 G, 4 G, 8 G or 10 G. The switch element includes a clock configuration module for providing a clock signal that is based on the data transfer rate. A receive segment of the fibre channel port sends a signal to a transmit segment to avoid an under flow condition. The receive segment also waits for a certain frame length after a fibre channel frame is written and before the fibre channel frame is read, depending upon a data transfer rate of a source port. Multiple lanes may be configured as a single 10 G multi lane port or as multiple individual ports.