Method and apparatus for transfer of information using optical fiber connections

• US 6,338,083 B1
• Filed: 08/20/1999
• Issued: 01/08/2002
• Est. Priority Date: 10/14/1998
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Elliott, Joseph C., Huang, Catherine C., Flanagan, John R., Ricci, Louis W., Casper, Daniel F., Frazier, Giles R., Dugan, Robert J.
• Primary Examiner(s): Harrell, Robert B.
• Application Number:
  US09/379,129
• Time in Patent Office: 872 Days
• Field of Search: 709/200, 709/213, 709/227, 709/229
• US Class Current: 709/213
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00
• CPC Class Codes: G06F 11/1443 Transmit or communication errors

Abstract

The present invention provides for a method of transferring information in a network computing system environment. The network environment includes a main storage coupled to a channel subsystem with a plurality of channels in processing communication with a control unit capable of coupling to a plurality of input/output devices. First packets of data are concurrently sent to and from the main storage. The operation of certain channel functions are also transferred to the control unit so that each command does not require a command response or an end notification response. Finally by certain commands are combined with the associated data of one or more of the data packets. In one embodiment of the present invention, an optical fabric is also in processing communication with said channels and control unit.

Claims

1. An apparatus for transferring information in a network computing system environment having a main storage coupled to a channel subsystem with a plurality of channels in processing communication with at least one control unit capable of coupling to a plurality of input/output devices, comprising:

a transmitter/receiver in said channel subsystem concurrently sending packets of data to and from said main storage;

a dispatcher in said channel subsystem transferring operation of certain channel functions to said control unit so that each command does not require a command response or an end notification response, combining commands with associated data within one or more of said data packets; and

,

a receiver in said control unit for receiving said combined commands with associated data transferred from said dispatcher.

2. The apparatus of claim 1, wherein a plurality of Channel Control Words (CCWs) are pipelined together in order to send associated processed data and commands to said control unit without any need for interlocking responses from said control unit.

3. The apparatus of claim 2, wherein each Write CCW is sent as one sequence.

4. The apparatus of claim 3, wherein if a Write CCW is longer than a certain length, any portion of said Write that exceeds said length is sent as a separate data sequence.

5. The apparatus of claim 4, wherein said length is equal to 4K.

6. The apparatus of claim 2, wherein said CCWs are chained further comprising a first eliminator eliminating all intermediate Status Sequences.

7. The apparatus of claim 2, wherein each Read CCW is sent as one sequence.

8. The apparatus of claim 1, wherein said channels and control unit are in processing communication with an optical fiber.

9. The apparatus of claim 8, wherein said transferring of information involves time division multiplexing of multiple exchanges over the same fiber optic link.

10. The apparatus of claim 9, wherein said multiplexing involves multiple channel programs to be exchanged at the same time with different devices.

11. The apparatus of claim 8, wherein said fabric has at least one optical fiber.

12. The apparatus of claim 1, wherein said channel subsystem is in processing communication with a storage control element coupled to said main storage.

13. The apparatus of claim 12, wherein said storage control element is also in processing communication with at least one central processing unit.

14. The apparatus of claim 1, wherein the environment has a plurality of control units are and at least one control unit is dedicated to each input/output device.

20. The method of claim 7, wherein each Write CCW is sent as one sequence.

21. The method of claim 20, wherein if a Write CCW is longer than a certain length, any portion of said Write that exceeds said certain length is sent as a separate data sequence.

22. The method of claim 21, wherein said certain length is equal to 4K.

15. A method for transferring information in a network computing system environment having a main storage coupled to a channel subsystem with a plurality of channels in processing communication with at least one control unit capable of coupling to a plurality of input/output devices, comprising:

concurrently sending packets of data to and from said main storage; and

,

transferring operation of channel functions to said control unit so that each command does not require a command response or an end notification response, thereby combining commands with associated data within one or more of said data packets.

16. The method of claim 15, wherein said channels and control unit are in processing communication with an optical fiber.

17. The method of claim 16, wherein said transferring of information involves time division multiplexing of multiple exchanges over the same fiber optic link.

18. The apparatus of claim 17, wherein said multiplexing involves multiple channel programs to be exchanged at the same time with different devices.

19. The method of claim 16, wherein said fabric has at least one optical fiber.

23. The method of claim 15, wherein a plurality of Channel Control Words (CCWs) are pipelined together in order to send associated processed data and commands to said control unit without interlocking responses from said control unit.

24. The method of claim 23, wherein said CCWs are chained without intermediate Status Sequences.

25. The method of claim 15, wherein the environment further comprises a plurality of control units and at least one control unit is dedicated to each input/output device.

26. The method of claim 23, wherein each Read CCW is sent as one sequence.

27. The method of claim 15, wherein said channel subsystem is in processing communication with a storage control element coupled to said main storage.

28. The method of claim 27, wherein said storage control element is also in processing communication with at least one central processing unit.

29. The method of claim 15, further comprising the step of receiving at said control unit, combined commands with associated data from said transferring operation.