System and method for optimizing frame routing in a network

• US 7,334,046 B1
• Filed: 08/05/2002
• Issued: 02/19/2008
• Est. Priority Date: 08/05/2002
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: QLogic Corporation (Marvell Technology Group Limited)
• Inventors: Betker, Steven Manning
• Primary Examiner(s): Harrell; Robert B.
• Application Number:
  US10/212,425
• Time in Patent Office: 2,024 Days
• Field of Search: 709238-239, 709/241, 370/238, 370/351, 370/352
• US Class Current: 709/241
• CPC Class Codes: G06F 13/426 using an embedded synchronisation, e.g. Firewire bus, Fibre Channel bus, SSA bus
• CPC Class Codes: G06F 2213/0008 High speed serial bus, e.g. Fiber channel
• CPC Class Codes: H04L 12/433 with asynchronous transmission, e.g. token ring, register insertion
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/12 Shortest path evaluation
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/28 using route fault recovery

Abstract

A method for routing Fibre Channel frames in a Fibre Channel system is provided. The method compares a cost associated with a pre-programmed preferred route when the pre-programmed preferred route has been pre-programmed to route Fibre Channel frames between a source Fibre Channel port and a destination Fibre Channel port; with a cost of at least one route for routing Fibre channel frames between the source Fibre Channel port and the destination port determined by using a standard Fibre Channel Fabric Shortest Path First (FSPF) protocol, and using the pre-programmed-preferred route to route Fibre Channel frames if the cost associated with the pre-programmed preferred route is lower than the cost associated with the at least one route determined by the standard Fibre Channel FSPF protocol.

Claims

1. A method for routing Fibre Channel frames in a Fibre Channel system, comprising:

storing a pre-programmed preferred route in a memory accessible to a processor of a Fibre Channel switch element to route Fibre Channel frames from a source Fibre Channel port to a destination Fibre Channel port;

comparing a cost associated with the pre-programmed preferred route;

with a cost associated with a lowest cost route that is determined by using a standard Fibre Channel Fabric Shortest Path First (FSPF) protocol;

using the pre-programmed-preferred route to route the Fibre Channel frames if the cost associated with the pre-programmed preferred route is equal to or lower than the cost associated with the lowest cost route determined by the standard Fibre Channel FSPF protocol; and

using a route determined by the standard Fibre Channel FSPF protocol if a preferred route has not been pre-programmed.

2. The method of claim 1, wherein the pre-programmed preferred route is specified to route frames between external Fibre Channel switch element ports.

3. The method of claim 1, wherein the pre-programmed preferred route is specified to route frames between internal modules of a multi-module Fibre Channel switch.

4. The method of claim 1, wherein the pre-programmed preferred route is pre-programmed by using a switch management module.

5. A Fibre Channel switch element, comprising:

a processor executing firmware code for comparing a cost associated with a pre-programmed preferred route stored in a memory that is accessible to the processor, with a cost associated with a lowest cost route determined by using a standard Fibre Channel Fabric Shortest Path First (FSPF) protocol, wherein the pre-programmed preferred route is pre-programmed to route frames between a source Fibre Channel port and a destination Fibre Channel port and the pre-programmed preferred route is used if the cost associated with the pre-programmed preferred route is equal to or lower than the cost associated with the lowest cost route determined by the standard Fibre Channel FSPF protocol.

6. The switch element of claim 5, wherein the pre-programmed preferred route is specified to route frames between external Fibre Channel switch element ports.

7. The switch element of claim 5, wherein the lowest cost route determined by using the standard Fibre Channel FSPF protocol is used to route Fibre Channel frames if the pre-programmed preferred route has not been pre-programmed in the memory.

8. The switch element of claim 5, wherein the pre-programmed preferred route is specified to route frames between internal modules of a multi-module Fibre Channel switch.

9. The switch element of claim 5, wherein the pre-programmed preferred route is pre-programmed by using a switch management module.

10. A Fibre Channel network, comprising:

a Fibre Channel switch element with a processor executing firmware code for comparing a cost associated with a pre-programmed preferred route stored in a memory accessible by the processor with a cost associated with a lowest cost route determined by using a standard Fibre Channel Fabric Shortest Path First (FSPF) protocol, wherein the pre-programmed preferred route is pre-programmed to route frames between a source Fibre Channel port and a destination Fibre Channel port; and

the pre-programmed preferred route is used if the cost associated with the pre-programmed preferred route is equal to or lower than the cost associated with the lowest cost route determined by the standard Fibre Channel FSPF protocol.

11. The switch element of claim 10, wherein the pre-programmed preferred route is specified to route frames between external Fibre Channel switch element ports.

12. The switch element of claim 10, wherein the lowest cost route determined by the standard Fibre Channel FSPF protocol is used to route frames if a preferred route has not been pre-programmed.

13. The switch element of claim 10, wherein the pre-programmed preferred route is specified for a particular switch.

14. The switch element of claim 10, wherein the preferred route is stored as a table in the memory accessible to the processor.