Software service handoff mechanism with a performance reliability improvement mechanism (PRIM) for a collaborative client-server system

• US 7,219,122 B1
• Filed: 04/23/2002
• Issued: 05/15/2007
• Est. Priority Date: 04/23/2001
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Kuang, Chang, Pena-Mora, Feniosky, Wang, Wei, Dwivedi, Gyanesh, Vadhavkar, Sanjeev
• Primary Examiner(s): Dharia; Rupal
• Assistant Examiner(s): Scuderi; Philip S.
• Application Number:
  US10/128,155
• Time in Patent Office: 1,848 Days
• Field of Search: 709201-207, 714/6
• US Class Current: 709/201
• CPC Class Codes: G06F 11/2023 Failover techniques
• CPC Class Codes: G06F 11/2035 without idle spare hardware
• CPC Class Codes: G06F 11/2048 where the redundant components share neither address space nor persistent storage
• CPC Class Codes: G06F 11/2097 maintaining the standby controller/processing unit updated initialisation or re-synchronisation thereof G06F11/1658 and subgroups
• CPC Class Codes: G06F 16/27 Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes

Abstract

A collaborative client-server system having performance reliability improvement (PRIM) includes collaboration techniques for sharing server data among two or more servers, each server coupled to one or more client computers. A communication link between a client computer and a server is handed off to another respective one of the two or more servers under a variety of conditions. Hand off conditions include, congestion of the server processing load, congestion of the communication link between the client computer and the server, and loss of data signal integrity between the client computer and the server.

Claims

1. A collaboration system comprising:

a first collaboration server;

a first collaboration server repository coupled to the first collaboration server, wherein the first collaboration server repository has a first copy of a collaboration application and first collaboration server data associated with the first copy of the collaboration application stored therein;

a first collaboration engine coupled to the first collaboration server;

a second collaboration server, wherein the first and second collaboration servers are adapted to operate in a collaboration session;

a second collaboration server repository coupled to the second collaboration server, wherein the second collaboration server repository has a second copy of the collaboration application, second collaboration server data associated with the second copy of the collaboration application, and a portion of the first collaboration server data stored therein, wherein the portion of the first collaboration server data is automatically updated in real time to reflect changes in the first collaboration server data; and

a second collaboration engine coupled to the second collaboration server and coupled to the first collaboration engine, wherein the first collaboration engine is adapted to transfer first collaboration application information associated with operation of the first copy of the collaboration application to the second collaboration engine and the second collaboration engine is adapted to transfer second collaboration application information associated with operation of the second copy of the collaboration application to the first collaboration engine.

2. The collaboration system of claim 1, wherein the portion of the first collaboration server data includes a complete copy of the first collaboration server data.

3. The collaboration system of claim 1, wherein the portion of the first collaboration server data includes a first partial copy of the first collaboration server data.

4. The collaboration system of claim 3, further comprising:

a third collaboration server coupled to at least one of the first and the second collaboration servers;

a third collaboration server repository coupled to the third collaboration server, wherein the third collaboration server repository has third collaboration server data and a second partial copy of the first collaboration server data stored therein; and

a third collaboration engine coupled to the third collaboration server and coupled to the first and second collaboration engines.

5. The collaboration system of claim 4, wherein the first and the second partial copies of the first collaboration server data can be accessed by the second and the third collaboration engines respectively to provide the first collaboration server data.

6. The collaboration system of claim 4, further comprising:

a fourth collaboration server coupled to at least one of the first, second, and third collaboration servers;

a fourth collaboration server repository coupled to the fourth collaboration server, wherein the fourth collaboration server repository has error correcting data stored therein, wherein the error correcting data is adapted to allow reconstruction of the first collaboration server data from either the first partial copy of the first collaboration server data or the second partial copy of the first collaboration server data; and

a fourth collaboration engine coupled to the fourth collaboration server and coupled to the first, second, and third collaboration engines.

7. The collaboration system of claim 1, further comprising:

a client computer coupled with a client coupling to a selected one of the first and second collaboration servers, wherein a selected one of the first and the second collaboration engines is adapted to select the client coupling.

8. The collaboration system of claim 7, wherein the selected one of the first and second collaboration engines is adapted to seamlessly hand off the client coupling between the first and the second collaboration servers during the collaboration session in accordance with data congestion associated with the client coupling.

9. The collaboration system of claim 7, wherein the selected one of the first and second collaboration engines is adapted to seamlessly hand off the client coupling between the first and the second collaboration servers during the collaboration session in accordance with processing congestion associated with the first and the second collaboration servers.

10. The collaboration system of claim 7, wherein the selected one of the first and second collaboration engines is adapted to seamlessly hand off the client coupling between the first and the second collaboration servers during the collaboration session in accordance with a quality of coupling integrity associated with the client coupling.

11. The collaboration system of claim 7, wherein the client coupling is a radio frequency (RF) communication link.

12. The collaboration system of claim 11, wherein the selected one of the first and second collaboration engines is adapted to seamlessly hand off the client coupling between the first and the second collaboration servers during the collaboration session in accordance with RF field strength associated with the RF communication link.

13. The collaboration system of claim 11, wherein the selected one of the first and second collaboration engines is adapted to seamlessly hand off the client coupling between the first and the second collaboration servers during the collaboration session in accordance with geographical positions of the client computer and of the first and second collaboration servers.

14. The collaboration system of claim 1, wherein, if the first collaboration server loses communication with the collaboration session or become inoperative, the collaboration session can continue without loss of the first collaboration server data and without loss of the first collaboration application information, by using the second collaboration server.

15. A collaboration method comprising:

storing first collaboration server data and a first copy of a collaboration application in a first collaboration server storage area associated with a first collaboration server;

storing second collaboration server data, a portion of the first collaboration server data, and a second copy of the collaboration application in a second collaboration server storage area associated with a second collaboration server;

collaborating with the first and second collaboration servers in a collaboration session;

automatically updating the portion of the first collaboration server data in real time to reflect changes in the first collaboration server data;

transferring, via a first collaboration engine, first collaboration application information associated with operation of the first copy of the collaboration application to the second collaboration server; and

transferring, via a second collaboration engine, second collaboration application information associated with operation of the second copy of the collaboration application to the first collaboration server, wherein the first collaboration engine is associated with the first collaboration server and the second collaboration engine is associated with the second collaboration server.

16. The collaboration method of claim 15, wherein the portion of the first collaboration server data includes a complete copy of the first collaboration server data.

17. The collaboration method of claim 15, wherein the portion of the first collaboration server data includes a first partial copy of the first collaboration server data.

18. The collaboration method of claim 17, further comprising:

storing third collaboration server data in a third server storage area associated with a third collaboration server, wherein the third collaboration server is coupled to at least one of the first collaboration server and the second collaboration server, wherein the third collaboration server data includes a second partial copy of the first collaboration server data.

19. The collaboration method of claim 18, further comprising:

accessing the first and the second partial copies of the first collaboration server with the second and third collaboration servers respectively to provide the first collaboration server data.

20. The collaboration method of claim 18, further comprising:

storing error correcting data in a fourth collaboration server storage area associated with a fourth collaboration server, wherein the fourth collaboration server is coupled to at least one of the first, second, and third collaboration servers, wherein the error correcting data is adapted to allow reconstruction of the first collaboration server data from either the first partial copy of the first collaboration server data or the second partial copy of the first collaboration server data.

21. The collaboration method of claim 15, further comprising:

selecting a client coupling between a client computer and a selected one of the first and second collaboration servers, wherein a selected one of the first and second collaboration engines is adapted to select the client coupling.

22. The collaboration method of claim 21, further comprising:

seamlessly handing off the client coupling between the first and the second collaboration servers during the collaboration session, wherein the handoff is determined by data congestion associated with the client coupling.

23. The collaboration method of claim 21, further comprising:

seamlessly handing off the client coupling between the first and the second collaboration servers during the collaboration session, wherein the handoff is determined by processing congestion associated with the first and the second collaboration servers.

24. The collaboration method of claim 21, further comprising:

seamlessly handing off the client coupling between the first and the second collaboration servers during the collaboration session, wherein the handoff is determined by a loss of connection integrity associated with the client coupling.

25. The collaboration server of claim 21, wherein the client coupling is a radio frequency (RF) communication link.

26. The collaboration method of claim 25, further comprising:

determining the RF field strength associated with the client coupling; and

seamlessly handing off the client coupling between the first and second collaboration servers during the collaboration session, wherein the handoff is determined by the RF field strength.

27. The collaboration method of claim 25, further comprising:

determining geographic positions of the client computer and the first and second collaboration servers; and

seamlessly handing off the client coupling between the first and the second collaboration servers during the collaboration session, wherein the handoff is determined by the geographic positions.

28. The collaboration method of claim 15, further comprising

continuing the collaboration session without loss of the first collaboration server data and without loss of the first collaboration application information if the first collaboration server loses communication with the collaboration session or become inoperative, by using the second collaboration server.

29. A computer-readable storage medium encoded with computer-readable code, comprising:

instructions for storing first collaboration server data and a first copy of a collaboration application in a first server storage area associated with a first collaboration server;

instructions for storing second collaboration server data, a portion of the first collaboration server data, and a second copy of the collaboration application in a second server storage area associated with a second collaboration server,

instructions for collaborating with the first and second collaboration servers in a collaboration session;

instructions for automatically updating the portion of the first collaboration server data in real time to reflect changes in the first collaboration server data;

instructions for transferring, via a first collaboration engine, first collaboration application information associated with operation of the first copy of the collaboration application to the second collaboration server; and

instructions for transferring, via a second collaboration engine, second collaboration application information associated with operation of the second copy of the collaboration application to the first collaboration server, wherein the first collaboration engine is associated with the first collaboration server and the second collaboration engine is associated with the second collaboration server.

30. The computer-readable storage medium of claim 29, wherein the portion of the first collaboration server data includes a complete copy of the first collaboration server data.

31. The computer-readable storage medium of claim 29, wherein the portion of the first collaboration server data includes a first partial copy of the first collaboration server data.

32. The computer-readable storage medium of claim 31, further comprising:

instructions for storing third collaboration server data in a third server storage area associated with a third collaboration server, wherein the third collaboration server is coupled to at least one of the first collaboration server and the second collaboration server, wherein the third collaboration server data includes a second partial copy of the first collaboration server data.

33. The computer-readable storage medium of claim 32, further comprising:

instructions for accessing the first and the second partial copies of the first collaboration server data with the second and third collaboration servers respectively to provide the first collaboration server data.

34. The computer-readable storage medium of claim 32, further comprising:

instructions for storing error correcting data in a fourth server storage area associated with a fourth collaboration server, wherein the fourth collaboration server is coupled to at least one of the first, second, and third collaboration servers, wherein the error correcting data is adapted to allow reconstruction of the first collaboration server data from either the first partial copy of the first collaboration server data or the second partial copy of the first collaboration server data.

35. The computer-readable storage medium of claim 29, further comprising:

instructions for selecting a client coupling between a client computer and a selected one of the first and second collaboration servers, wherein a selected one of the first and second collaboration engines is adapted to select the client coupling.

36. The computer-readable storage medium of claim 35, further comprising:

instructions for seamlessly handing off the client coupling between the first and the second collaboration servers during the collaboration session, wherein the handoff is determined by data congestion associated with the client coupling.

37. The computer-readable storage medium of claim 35, further comprising:

instructions for seamlessly handing off the client coupling between the first and the second collaboration servers during the collaboration session, wherein the handoff is determined by processing congestion associated with the first and the second collaboration servers.

38. The computer-readable storage medium of claim 35, further comprising:

instructions for seamlessly handing off the client coupling between the first and the second collaboration servers during the collaboration session, wherein the handoff is determined by a loss of connection integrity associated with the client coupling.

39. The collaboration server of claim 35, wherein the client coupling is a radio frequency (RF) communication link.

40. The computer-readable storage medium of claim 39, further comprising:

instructions for determining the RF field strength associated with the client coupling; and

instructions for seamlessly handing off the client coupling between the first and second collaboration servers during the collaboration session, wherein the handoff is determined by the RF field strength.

41. The computer-readable storage medium of claim 39, further comprising:

instructions for determining geographic positions of the client computer and the first and second collaboration servers; and

instructions for seamlessly handing off the client coupling between the first and the second collaborations servers during the collaboration session, wherein the handoff is determined by the geographic positions.

42. The computer-readable storage medium of claim 29, further comprising:

instructions for continuing the collaboration session without loss of the first collaboration server data and without loss of the first collaboration application information if the first collaboration server loses communication with the collaboration session or become inoperative, by using the second collaboration server.