Method and system for fibre channel arbitrated loop acceleration

• US 20050013318A1
• Filed: 07/12/2004
• Published: 01/20/2005
• Est. Priority Date: 07/16/2003
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: QLogic Corporation (Marvell Technology Group Limited)
• Inventors: Fike, John M., Hareski, Patricia E.
• Granted Patent: US 7,463,646 B2
• Time in Patent Office: Days
• US Class Current: 370/462
• CPC Class Codes: H04L 49/602 Multilayer or multiprotocol switching, e.g. IP switching

Abstract

A fibre channel switch element with an acceleration device that connects plural fibre channel devices in an arbitrated loop and monitors frames sent during a loop initialization process is provided. The acceleration device creates an AL_PA table selected by each fibre channel device, wherein the AL_PA table is used for port selection; and during an arbitration process sends a benign primitive to non-arbitrating devices. The acceleration device includes, a global arbitration module, a state machine module, and a matrix for connecting plural fibre channel devices.

Claims

1. A fibre channel switch element, comprising:

an acceleration device that connects plural fibre channel devices in an arbitrated loop and monitors frames sent during a loop initialization process and creates an AL_PA table selected by each fibre channel device, wherein the AL_PA table is used for port selection; and

during an arbitration process sends a benign primitive to non-arbitrating devices.

2. The switch element of claim 1, wherein during an open process, the acceleration device connects a fibre channel device that wins arbitration to a destination device so that an open primitive can be sent directly to the destination device.

3. The switch element of claim 1, wherein non-destination devices receive a benign primitive during the open process to maintain proper loop state machine state.

4. The switch element of claim 1, wherein during an open replicate process, the acceleration device after it receives an open replicate primitive creates a spray pattern for all ports with which a fibre channel device intends to communicate.

5. The switch element of claim 1, wherein the acceleration device includes a global arbitration module, a state machine module, and a matrix for connecting plural fibre channel devices.

6. The switch element of claim 5, wherein only one state machine is used for describing an arbitrated loop state.

7. An acceleration device used by a fibre channel switch element, comprising:

a global arbitration module,

a state machine module, and a matrix for connecting plural fibre channel devices;

wherein the acceleration device connects plural fibre channel devices in an arbitrated loop and monitors frames sent during a loop initialization process and creates an AL_PA table selected by each fibre channel device, wherein the AL_PA table is used for port selection; and

during an arbitration process sends a benign primitive to non-arbitrating devices.

8. The acceleration device of claim 7, wherein during an open process, the acceleration device connects a fibre channel device that wins arbitration to a destination device so that an open primitive can be sent directly to the destination device.

9. The acceleration device of claim 8, wherein non-destination devices receive a benign primitive during the open process to maintain proper loop state machine state.

10. The acceleration device of claim 7, wherein during an open replicate process, the acceleration device after it receives an open replicate primitive creates a spray pattern for all ports with which a fibre channel device intends to communicate.

11. The switch element of claim 7, wherein only one state machine is used for describing an arbitrated loop state.

12. A method for accelerating traffic in a fibre channel arbitrated loop topology having a fibre channel switch element with an acceleration device, comprising:

monitoring fibre channel frames during a loop initialization process;

creating an AL_PA table for fibre channel devices connected in the arbitrated loop and using the AL_PA table for identifying ports.

13. The method of claim 12, further comprising:

sending benign primitives to non-arbitrating devices during an arbitration process.

14. The method of claim 12, further comprising:

connecting a fibre channel device that sends an OPEN primitive to a destination port; and

sending a benign primitive to non-destination device connected in the arbitrated loop.

15. The method of claim 14, further comprising:

creating a spray pattern after receiving an open replicate primitive from a fibre channel device; and

sending frames to plural destination ports at the same time.