Self-description extended link service for networks

• US 6,347,334 B1
• Filed: 01/06/1999
• Issued: 02/12/2002
• Est. Priority Date: 01/06/1999
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.), International Business Machines Corporation
• Original Assignee: Mcdata Corporation (Broadcom, Inc.)
• Inventors: Elliott, Joseph C., Fredericks, Kenneth J., OʼDonnell, Michael E.
• Primary Examiner(s): Dinh, Dung C.
• Application Number:
  US09/225,949
• Time in Patent Office: 1,133 Days
• Field of Search: 709/220, 709/221, 709/222, 709/223, 709/224, 709/230, 710/10, 710/104, 370/241, 370/244, 370/245, 370/250, 370/248
• US Class Current: 709/220
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches
• CPC Class Codes: H04L 49/357 Fibre channel switches

Abstract

A method for implementing a link level service in a computer network having a first port device and a second port device. Node identification data is stored in the second port device. A physical-layer communications coupling is provided between the first port device and the second port device which may be a point-to-point, loop, or switched circuit connection. The first port device sends a request node identification (RNID) message addressed to the second port device. The second port device creates an accept message and copies stored node identification data into the accept message. The second port device sends the accept message to the first port device.

Claims

1. A method for implementing a link level service in a computer network comprising the steps of:

providing a first port device;

providing a second port device;

storing node identification data in the first and second port device;

providing a physical-layer communications coupling between the first port device and the second port device;

causing the first port device to send a request node identification (RNID) message addressed to the second port device;

transporting the RNID message to the second port device using the communications coupling;

creating an Accept message in the second port device;

copying the node identification data stored in the second port device into the second port device'"'"'s Accept message;

causing the second port device to send the accept message to the first port device; and

transporting the accept message to the first port device using the communications coupling.

2. The method of claim 1 further comprising the steps of:

storing node identification data in the first port device;

causing the second port device to send a request node identification (RNID) message addressed to the first port device;

transporting the RNID message to the first port device using the communications coupling;

creating an accept message in the first port device;

copying the node identification data stored in the first port device into the first port device'"'"'s accept message;

causing the first port device to send the accept message to the second port device; and

transporting the accept message to the second port device using the communications coupling.

3. The method of claim 1 wherein the communications coupling comprises a fibre channel fabric and the step of transporting further comprises using an FC-4 layer protocol.

4. The method of claim 1 wherein the communications coupling comprises a fibre channel fabric and the step of transporting further comprises using an FC-2 layer protocol.

5. The method of claim 1 wherein the communications coupling comprises a fibre channel fabric and the step of transporting further comprises using an FT-1 transport layer protocol.

6. The method of claim 1 wherein the node identification data comprises product identification information related to a product in which the first and second port device is implemented and the method further comprises a step of making the product identification information available to the upper layer protocol (ULP) operating on the first and the second port device.

7. The method of claim 1 further comprising:

executing an upper layer protocol (ULP) operating on the first and second port device;

passing the node identification data to the ULP; and

causing the ULP to store the node identification information in a configuration database.

8. The method of claim 7 further comprising:

causing the ULP to compare the NID to a saved system configuration to determine if a system configuration change has occurred.

9. The method of claim 7 further comprising:

causing the ULP to associate the node identification information with historical failure statistics for the second port device.

10. The method of claim 7 further comprising:

causing the ULP to use the node identification information to autoconfigure itself for communications with the second port device.

11. The method of claim 1 further comprising:

causing the first and second port device to repeat the step of sending the RNID message until valid and current node-identification data is acquired from the other port device.

12. The method of claim 1 wherein the RNID message includes a type field indicating an FC-4 device type and the step of creating an Accept message is performed only when the first and second port device are associated with the FC-4 device type indicated in the type field of the RNID message.

13. A system for communicating data comprising:

a first port device;

a second port device;

a data structure within the first and second port device storing node identification data;

a physical-layer communications coupling between the first port device and the second port device;

an upper layer protocol (ULP) operating on the first port device and causing the first port device to generate a request node identification (RNID) message addressed to the second port device;

a transmit device within the first port device and operative to receive and send the RNID message over the communications coupling;

a link-level facility operating in the second port device for receiving and recognizing the RNID message, creating an accept message addressed to the first port device, and copying the stored node identification data into the accept message; and

a transmit device within the second port device and operative to receive and send the accept message over the communications coupling.

14. The system of claim 13 further comprising:

a data structure within the first port device storing the node identification data transmitted from the second port device.

15. The system of claim 13 wherein the communications coupling comprises a switch.

16. The system of claim 13 wherein the first port device comprises a fibre channel node port.

17. The system of claim 13 wherein the first port device comprises a fibre channel fabric port.

18. The system of claim 13 wherein the first port device comprises a fibre channel expansion port.

19. The system of claim 13 wherein the first port device comprises a fibre channel loop port.

20. The system of claim 13 wherein the RNID message includes a type field indicating an FC-4 device type and the link level facility is configured to create an accept message only when the second port device is associated with the FC-4 device type indicated in the type field of the RNID message.

21. In a network having at least a first computer having a first port device and a second computer having a second port device, a self-description apparatus for providing node identification data used to diagnose fibre channel network configuration within the apparatus being operative to implement a link level service in the network, comprising:

a first code portion data packet comprising code configured to cause the first computer to generate a request node identification (RNID) message addressed to the second computer, the RNID message indicating an FC-4 device type;

a second code portion data packet comprising code configured to cause the second computer to create an accept message in response to the RNID message when the second computer includes a device having the indicated FC-4 device type;

a third code portion data packet comprising code configured to cause the second computer to copy stored node identification data into the accept message; and

a fourth code portion data packet comprising code configured to cause the second computer to send the accept message to the first computer.