Arbitrated loop address management apparatus method and system

• US 20060109844A1
• Filed: 11/19/2004
• Published: 05/25/2006
• Est. Priority Date: 11/19/2004
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Cagno, Brian James, Lucas, Gregg Steven, Bomhoff, Matthew David, Seidel, Andrew Ellis, Gan Qiu, Kenny Nian
• Granted Patent: US 7,782,845 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• CPC Class Codes: H04L 12/42 Loop networks
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming

Abstract

An apparatus, system, and method are disclosed for automatically and transparently managing addresses in an arbitrated loop network. An arbitrated loop network switch is programmed with an address map and configured with the necessary modules to monitor an address assignment process and associate soft assigned addresses claimed during the address arbitration process with physical slot addresses. In one embodiment, the address fields of packets addressing a specific physical slot are changed (in route) to the soft address assigned during the address arbitration process. The entire process may be transparent to the rest of the network and to users. The present invention facilitates maintaining a physically ordered addressing scheme despite any soft addressing that occurs during loop initialization.

Claims

1. An apparatus for managing messaging in an arbitrated loop network, the apparatus comprising:

an address map configured to associate desired addresses with assigned addresses; and

an address assignment monitor configured to monitor an address assignment process in an arbitrated loop network and populate the address map;

a switching array configured to route packets to devices attached to the arbitrated loop network using the address map.

2. The apparatus of claim 1, wherein the desired addresses correspond to specific ports of the switching array.

3. The apparatus of claim 2, wherein the switching array is further configured to change from a loop mode to a point-to-point mode.

4. The apparatus of claim 1, further comprising a memory configured to store the address map.

5. The apparatus of claim 4, wherein the memory is a non-volatile memory.

6. The apparatus of claim 1, further comprising a networked device operably connected to the switching array.

7. The apparatus of claim 6, wherein the networked device is a storage devices.

8. The apparatus of claim 7, further comprising an enclosure configured to enclose the switching array and the networked device.

9. A method for managing messaging in an arbitrated loop network, the method comprising:

monitoring an address assignment process in an arbitrated loop network;

populating an address map during an address assignment process, the address map configured to associate desired addresses with assigned addresses; and

routing packets to devices attached to the arbitrated loop network using the address map.

10. The method of claim 9, wherein the desired addresses correspond to specific ports of a switching array.

11. The method of claim 9, further comprising changing the switching array from a loop mode to a point-to-point mode.

12. The method of claim 9, wherein routing packets in the arbitrated loop comprises point-to-point routing via the switching array.

13. The method of claim 9, further comprising changing a destination address field in a packet.

14. A system for managing messaging in an arbitrated loop network, the system comprising:

an arbitrated loop network; and

a switch configured to monitor an address assignment process in the arbitrated loop network, update an address map associated with the switch, and route packets to devices attached to the arbitrated loop network using the address map.

15. The system of claim 14, wherein the address map is configured to map desired addresses to assigned addresses;

16. The system of claim 14, further comprising a plurality of networked devices;

17. The system of claim 16, wherein the plurality of networked devices comprise a plurality of storage devices.

18. The system of claim 16, further comprising an enclosure configured to enclose at least one networked device of the plurality of networked devices.

19. The system of claim 14, further comprising a host.

20. The system of claim 14, further comprising a host bus adapter.

21. A machine readable medium tangibly embodying a program of machine-readable instructions executable by a digital processing, the machine readable instructions configured to execute a method for managing messaging in an arbitrated loop network, the method comprising:

monitoring an address assignment process in an arbitrated loop network;

populating an address map during an address assignment process, the address map configured to associate desired addresses with assigned addresses; and

routing packets to devices attached to the arbitrated loop network using the address map.

22. The machine readable medium of claim 21, wherein the desired addresses correspond to specific ports on a switching array.

23. The machine readable medium of claim 21, wherein the method further comprises changing the switching array from a loop mode to a point-to-point mode.

24. The machine readable medium of claim 21, wherein routing packets in the arbitrated loop comprises point-to-point routing via the switching array.

25. An apparatus for managing messaging in an arbitrated loop network, the method comprising:

means for monitoring an address assignment process in an arbitrated loop network;

means for populating an address map during an address assignment process, the address map configured to associate desired addresses with assigned addresses; and

means for routing packets to devices attached to the arbitrated loop network using the address map.