Client-server model for synchronization of files

• US 20020174180A1
• Filed: 03/15/2002
• Published: 11/21/2002
• Est. Priority Date: 03/16/2001
• Status: Active Grant

• Current Assignee: Micro Focus Software, Inc. (Open Text Corporation)
• Original Assignee: Novell Incorporated (Open Text Corporation)
• Inventors: Wein, Josef, Brown, David K., Rolander, Thomas A., Silberstein, Robert D.
• Granted Patent: US 7,734,826 B2
• Time in Patent Office: Days
• US Class Current: 709/203
• CPC Class Codes: G06F 16/1787 Details of non-transparently synchronising file systems
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation
• CPC Class Codes: Y10S 707/99943 Generating database or data structure, e.g. via user interface
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A server stores files. Distributed clients access the server, to learn about changes made to the files on the server, and to push local changes of the files onto the server. A synchronization application is used to synchronize the clients and server, synchronizing metadata and selected files.

Claims

1. A client synchronization application running on a client, comprising:

means for comparing a client sync index (CSI) with a server sync index (SSI); and

means for determining if a client is in sync with a server based on the compared CSI and SSI.

2. A client synchronization application according to claim 1, further comprising a client sync data (CSD).

3. A client synchronization application according to claim 2, further comprising means for comparing the CSD with a server sync data (SSD).

4. A client synchronization application according to claim 3, further comprising means for updating the CSD responsive to the compared CSD and SSD.

5. A client synchronization application according to claim 1, further comprising a filter driver to monitor activity on the client.

6. A client synchronization application according to claim 1, further comprising a directory entry stored on the client.

7. A client synchronization application according to claim 6, wherein:

the directory entry is a file; and

the apparatus further comprises a filter driver to monitor activity on the client and to interrupt the client synchronization application if a second application accesses the file.

8. A client synchronization application according to claim 6, further comprising a metadata item for the directory entry, the metadata item including a client ID and server ID.

9. A client synchronization application according to claim 6, wherein:

the directory entry is a file; and

the client synchronization application further comprises means for partially uploading or downloading the file.

10. A client synchronization application according to claim 9, wherein:

the apparatus further comprises;

a message digest array (MDA) for the file;

means for receiving a second MDA from the server; and

the means for partially uploading or downloading includes means for comparing the MDA and the second MDA.

11. A client synchronization application according to claim 10, wherein the MDA is stored with a metadata item for the file.

12. A client synchronization application according to claim 10, further comprising means for generating the MDA for the file.

13. A client synchronization application according to claim 6, further comprising means for storing a change time to the directory entry.

15. An applet according to claim 14, further comprising means for encrypting data to be transmitted to the server.

16. An applet according to claim 14, further comprising means for decrypting data received from the server.

20. A method according to claim 19, further comprising:

receiving a server sync data (SSD) from the synchronization file system;

comparing a client sync data (CSD) and the SSD to determine what updates to make to the client; and

updating a directory entry on the client and a metadata item for the directory entry on the client.

21. A method according to claim 20, wherein comparing a client sync data (CSD) and the SSD includes:

identifying a server ID (SID) in the SSD but not in the CSD; and

determining that a file exists on the server and missing on the client.

22. A method according to claim 20, further comprising updating the CSD based on the comparison of the CSD and the SSD.

23. A method according to claim 20, further comprising updating a metadata item based on the SSD.

24. A method according to claim 19, further comprising:

requesting a file from the synchronization file system by a server ID;

receiving the file from the synchronization file system; and

storing the file on the client.

25. A method according to claim 24, wherein:

requesting a message digest array (MDA) for the file; and

receiving the MDA from the synchronization file system.

26. A method according to claim 25, wherein:

requesting a file includes requesting a block of the file from the synchronization file system; and

receiving the file includes receiving the block of the file from the synchronization file system.

28. A method according to claim 27, wherein:

the directory entry is a file; and

transmitting a directory entry includes;

transmitting a second SID, a parent directory SID, and a name for the file to the synchronization file system; and

receiving an indication whether the synchronization file system was able to find a previous version of the file.

29. A method according to claim 27, wherein transmitting a directory entry further includes:

requesting a message digest array (MDA) from the synchronization file system;

receiving the MDA from the synchronization file system;

computing an MDA for the file; and

comparing the computed and received MDAs.

30. A method according to claim 29, wherein transmitting a directory entry further includes transmitting a block of the file.

14. An applet running on a browser installed on a client, comprising:

means for processing a server sync data (SSD); and

means for enabling user interaction with files on a server.

17. A library providing access to an account on a server by a client of the library, the library comprising:

means for processing a server sync data (SSD);

means for interacting with the client; and

means for enabling interaction with files on the server.

18. A client-server apparatus for supporting synchronization between a client and a server, comprising:

a synchronization file system installed on the server, including;

a directory entry;

a metadata item for the directory entry; and

a server sync index (SSI);

a client synchronization application installed on the client, the client remote from the server, the client synchronization application including;

means for comparing a client sync index (CSI) with the server sync index (SSI); and

means for determining if the client is in sync with the server based on the compared CSI and SSI; and

a network connecting the client to the server.

19. A method for a client to synchronize a first directory on the client with a second directory on a synchronization file system of a server, comprising:

transmitting a client sync index (CSI) to the synchronization file system;

receiving a server sync index (SSI) from the synchronization file system; and

using the CSI and SSI to determine whether the server and client are synchronized.

27. A method for a client to synchronize a first directory on the client with a second directory on a synchronization file system of a server, comprising:

transmitting a directory entry and a client metadata item for the directory entry to the synchronization file system;

receiving a server ID (SID) for the directory entry and a server sync index (SSI) from the synchronization file system;

inserting the SID into the client metadata item; and

updating a client sync data (CSD) .

31. A method for a client-server apparatus to synchronize a first directory on a synchronization file system of a server with a second directory on a client, comprising:

the client transmitting and the synchronization file system receiving a client sync index (CSI);

the synchronization file system transmitting and the client receiving a server sync index (SSI); and

using the CSI and SSI to determine whether the server and client are synchronized.

32. Computer-readable media containing a program for a client to synchronize a first directory on the client with a second directory on a synchronization file system of a server, comprising:

software for transmitting a client sync index (CSI) to the synchronization file system;

software for receiving a server sync index (SSI) from the synchronization file system; and

software for using the CSI and SSI to determine whether the server and client are synchronized.

33. Computer-readable media containing a program for a client to synchronize a first directory on the client with a second directory on a synchronization file system of a server, comprising:

software for transmitting a directory entry and a metadata item for the directory entry to the synchronization file system;

software for receiving a server ID (SID) for the directory entry and a server sync index (SSI) from the synchronization file system; and

software for inserting the SID into the metadata item.

36. A computer-readable signal according to claim 35, wherein the synchronization response message further includes a server sync data, including means for identifying a file.

37. A computer-readable signal according to claim 36, further comprising:

a block request message, including means for identifying a block in the file; and

a block transmission message, including means for providing the block in the file.

38. A computer-readable signal according to claim 35, further comprising:

a block transmission message, including;

means for identifying a file; and

means for providing a block in the file; and

a server receipt message, including means for providing a server sync index.

39. A computer-readable signal according to claim 38, wherein the block transmission message further includes means for providing a message digest for the block in the file.

34. Computer-readable media containing a program for a client-server apparatus to synchronize a first directory on a synchronization file system of a server with a second directory on a client, comprising:

software for the client transmitting and the synchronization file system receiving a client sync index (CSI);

software for the synchronization file system transmitting and the client receiving a server sync index (SSI); and

software for using the CSI and SSI to determine whether the server and client are synchronized.

35. A computer-readable signal comprising:

a synchronization request message, including;

means for identifying a synchronization request; and

means for providing a client sync index; and

a synchronization response message, including means for providing a server sync index.