Interfabric routing header for use with a backbone fabric

• US 20060023708A1
• Filed: 07/30/2004
• Published: 02/02/2006
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Brocade Communications Systems, Inc. (Broadcom, Inc.)
• Inventors: Chung, Daniel Ji Yong Park, McClanahan, Edward D., Wilson, Steven L., Makishima, Dennis Hideo, Snively, Robert Norman
• Granted Patent: US 8,532,119 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• 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

Abstract

A Fibre Channel router used to join fabrics. EX_ports are used to connect to the fabrics. The EX_port joins the fabric but the router will not merge into the fabric. Ports in the Fibre Channel router can be in a fabric, but other ports can be connected to other fabrics. Fibre Channel routers can be interconnected using a backbone fabric. Global, interfabric and encapsulation headers are developed to allow routing by conventional Fibre Channel switch devices in the backbone fabric and simplify Fibre Channel router routing. Phantom domains and devices must be developed for each of the fabrics being interconnected. Front phantom domains are present at each port directly connected to a fabric. Each of these is then connected to at least one translate phantom domain. Zoning is accomplished by use of a special LSAN zoning naming convention. This allows each administrator to independently define devices are accessible.

Claims

1. A carrier signal modulated with an augmented Fibre Channel frame that comprises:

a start of frame field;

an encapsulation header;

a standard Fibre Channel frame; and

an end of frame field;

wherein the encapsulation header is appended to the standard Fibre Channel frame such that the standard Fibre Channel frame is the payload of the augmented Fibre Channel frame.

2. The carrier signal of claim 1 wherein the encapsulation header is formatted substantially identically to a standard Fibre Channel frame header.

3. The carrier signal of claim 1 wherein the encapsulation header comprises a type field indicating that the augmented frame is part of an encapsulation tunnel.

4. The carrier signal of claim 1 wherein the augmented Fibre Channel frame further comprises an interfabric routing header.

5. The carrier signal of claim 4 wherein the interfabric routing header comprises a destination fabric identifier and a source fabric identifier.

6. The carrier signal of claim 5 wherein the interfabric header comprises a timestamp indicating an expiration time of the augmented Fibre Channel frame.

7. The carrier signal of claim 1 wherein the data field of the standard Fibre Channel frame comprises a global header field.

8. A method for routing Fibre Channel packets between a first device on a first fabric and a second device on a second fabric wherein the first and second fabrics are interconnected by a backbone fabric, the method comprising:

receiving a standard Fibre Channel packet from the first device, wherein a frame header of the standard Fibre Channel packet includes a source identifier corresponding to the first device in the first fabric and a destination identifier corresponding to a phantom representation in the first fabric of the second device;

changing the destination identifier of the standard Fibre Channel packet to correspond to the second device in the second fabric;

encapsulating the Fibre Channel packet within an encapsulation packet such that the payload of the encapsulation packet comprises the standard Fibre Channel packet; and

passing the encapsulation packet to the backbone fabric.

9. The method of claim 8 wherein encapsulating the standard Fibre Channel packet comprises adding an encapsulation header to the Fibre Channel packet.

10. The method of claim 9 wherein encapsulating the standard Fibre Channel packet further comprises adding a fabric routing header to the standard Fibre Channel packet.

19. A switching device for routing Fibre Channel packets between a first device in a first fabric and a second device in a second fabric, wherein the first and second fabrics are interconnected by a backbone fabric and wherein the switching device is configured to perform a method according to claim 8.

20. A network comprising one or more switching devices according to claim 19.

11. A method for routing Fibre Channel packets between a first device on a first fabric and a second device on a second fabric wherein the first and second fabrics are interconnected by a backbone fabric, the method comprising:

receiving from the backbone fabric an encapsulation packet, wherein the payload of the encapsulation packet is a standard Fibre Channel packet;

recovering the standard Fibre Channel packet from the encapsulation packet, wherein a frame header of the standard Fibre Channel packet includes a source identifier corresponding to the first device in the first fabric and a destination identifier corresponding to a the second device in the second fabric;

changing the source identifier of the standard Fibre Channel packet to correspond to a phantom representation in the second fabric of the first device; and

passing the standard Fibre Channel packet to the second device.

12. The method of claim 11 wherein recovering the standard Fibre Channel packet from the encapsulation packet comprises stripping an encapsulation header from the encapsulation packet.

13. The method of claim 12 wherein recovering the standard Fibre Channel packet from the encapsulation packet comprises stripping a fabric routing header from the encapsulation packet.

14. The method of claim 13 wherein changing the source identifier of the standard Fibre Channel packet to correspond to a phantom representation in the second fabric of the first device comprises deriving the phantom representation from information contained in the fabric routing header.

21. A switching device for routing Fibre Channel packets between a first device in a first fabric and a second device in a second fabric, wherein the first and second fabrics are interconnected by a backbone fabric and wherein the switching device is configured to perform a method according to claim 11.

22. A network comprising one or more switching devices according to claim 21

23. A switching device for routing Fibre Channel packets between a first device in a first fabric and a second device in a second fabric, wherein the first and second fabrics are interconnected by a backbone fabric and wherein the switching device is configured to perform a method according to claim 14.

24. A network comprising one or more switching devices according to claim 23.

15. A switching device for routing Fibre Channel packets between a first device in a first fabric and a second device in a second fabric, wherein the first and second fabrics are interconnected by a backbone fabric, the switching device comprising:

an ingress module connected to the first fabric and configured to receive a standard Fibre Channel packet from the first device, change a destination identifier of the standard Fibre Channel packet to correspond to the second device in the second fabric, encapsulate the standard Fibre Channel packet within an encapsulation packet such that the payload of the encapsulation packet comprises the standard Fibre Channel packet; and

an egress module connected to the backbone fabric and configured to receive the encapsulation packet from the ingress module and pass the encapsulation packet to the backbone fabric.

17. A network comprising one or more switching devices according to claim 15.

16. A switching device for routing Fibre Channel packets between a first device in a first fabric and a second device in a second fabric, wherein the first and second fabrics are interconnected by a backbone fabric, the switching device comprising:

an ingress module connected to the backbone fabric and configured to receive an encapsulation packet having as a payload a standard Fibre Channel packet, recover the standard Fibre Channel packet from the encapsulation packet, and change a source identifier of the standard Fibre Channel packet to correspond to a phantom representation in the second fabric of the first device; and

an egress module connected to the backbone fabric and configured to receive the standard Fibre Channel packet from the ingress module and pass the standard Fibre Channel packet to the second device.

18. A network comprising one or more switching devices according to claim 16.