Method and system for programmable data dependant network routing

• US 20050018680A1
• Filed: 07/20/2004
• Published: 01/27/2005
• Est. Priority Date: 07/21/2003
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: QLogic Corporation (Marvell Technology Group Limited)
• Inventors: Dropps, Frank R., Kohlwey, Ernest G., Verba, Craig M.
• Granted Patent: US 7,573,909 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 49/101 using crossbar or matrix
• CPC Class Codes: H04L 49/25 Routing or path finding in a switch fabric
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags
• CPC Class Codes: H04L 49/357 Fibre channel switches

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.

Claims

1. A method for routing fibre channel frames using a fibre channel switch element, comprising:

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.

2. The method of claim 1, wherein a fibre channel domain, area, a virtual storage area number and/or AL_PA values are used to index table rows.

3. The method of claim 1, wherein a valid route is determined by matching a correct word depth with a frame word depth.

4. The method of claim 1, wherein a frame'"'"'s D_ID is used to select a column for frame routing information.

5. The method of claim 1, wherein a frame'"'"'s S_ID value is used to select a column for frame routing information.

6. The method of claim 1, wherein a frame'"'"'s OX_ID is used to select a column for frame routing information.

13. The method of claim 1, wherein a frame'"'"'s TYPE field is used to select a column for frame routing information.

14. The method of claim 1, wherein other bits of a frame are used to select a column for frame routing information.

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

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 to route fibre channel frames.

8. The switch element of claim 7, wherein a frame'"'"'s D_ID is used to select a column for frame routing information.

9. The switch element of claim 7, wherein a frame'"'"'s S_ID value is used to select a column for frame routing information.

10. The switch element of claim 7 wherein a frame'"'"'s OX_ID is used to select a column for frame routing information.

11. The switch element of claim 7, further comprising:

logic for validating a frame route by performing word depth match.

12. The switch element of claim 7, wherein a register is used to load look up table entries and column entries are selected based on the column select signal.

15. The switch element of claim 7, wherein a frame'"'"'s TYPE field is used to select a column for frame routing information.

16. The switch of claim 7, wherein other bits of a frame are used to select a column for frame routing information.