Client store synchronization through intermediary store change packets

• US 7,778,962 B2
• Filed: 04/20/2005
• Issued: 08/17/2010
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Thomas, Michael W., Mahajan, Sameer S., Shah, Darshatkumar A., Novik, Lev, Pohlmann, Nils H., Maksimenka, Andrei
• Primary Examiner(s): Lee; Wilson
• Assistant Examiner(s): Le; Michael
• Application Number:
  US11/110,159
• Publication Number:
  US 20050246389A1
• Time in Patent Office: 1,945 Days
• Field of Search: 707/2, 707201-204, 707/610, 707/620
• US Class Current: 707/610
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores

Abstract

The subject invention pertains to systems and methods of data item synchronization. More specifically, the invention concerns synchronization of data entities utilizing an intermediary or shared storage system and associated data store. Each client sync device can include or be associated with an interface that facilitates communication between client synchronization devices and the intermediary storage system. The interface can send change information to the shared store utilizing change data packets including a data change attribute, a prerequisite knowledge attribute and a learned knowledge attribute. The data change attribute can specify changes to be made to certain data, while the attribute can include a complete copy or reference to a complete copy or single instance of data.

Claims

1. A method for synchronizing at least two computer systems, comprising the following steps:

providing at least two client computer systems, wherein each client computer system utilizes a first storage platform;

providing an intermediary computer system, wherein the intermediary computer system utilizes a second storage platform different from and lacking support for synchronization for the first storage platform;

connecting the intermediary computer system to each client computer system;

providing a synchronization adapter to each client computer system enabling the client computer system to logically synchronize with the intermediary computer system;

synchronizing each client computer system with the intermediary computer system via the adapter resident on each client computer system; and

synchronizing each client computer system with the other client computer systems by means of the intermediary computer system;

wherein changes to a first version of a file stored on a client computer system are synchronized to the intermediary computer system to allow a second version of the file stored on a different client computer system to be synchronized with the first version by the intermediary computer system performing the following steps;

receiving a change packet from the client computer system that identifies changes to the first version of the file that were made by the client computer system;

determining whether the first version of the file contains each change that has been synchronized to the intermediary computer system by comparing the identified changes in the change packet with change data associated with the file that is stored on the intermediary computer system such that;

upon determining that the first version of the file contains each change that has been synchronized to the intermediary computer system, the intermediary computer system replaces the change data with the identified changes in the change packet, whereas

upon determining that the first version of the file does not contain each change that has been synchronized to the intermediary computer system, the intermediary computer system generates an exception and does not replace the change data with the identified changes in the change packet.

2. The method of claim 1, wherein replacing the change data with the identified changes in the change packet comprises writing the change packet to a packet store on the intermediary computer system, the change packet including the size and last modified date associated with the file.

3. The method of claim 2, wherein the change data and the change packet both include a last modified time and size for the file, and wherein comparing the identified changes in the change packet with change data associated with the file comprises:

retrieving a last modified time and size of the file from the change data;

retrieving the last modified time and size of the file from the change packet; and

comparing the last modified time and size from the change data with the last modified time and size from the change packet.

4. The method of claim 3, further comprising first read locking the change data and unlocking the change data after retrieving the change data.

5. The method of claim 1, further comprising write locking the change data prior to determining whether the first version of the file contains each change that has been synchronized to the intermediary computer system and unlocking the change data after it is replaced or an exception is generated.

6. The method of claim 1, receiving a change packet comprises receiving a change packet identifying single instance data.

7. A computer storage medium storing computer executable instructions which when executed by a processor perform steps for synchronizing at least two computer systems, comprising the following steps:

providing at least two client computer systems, wherein each client computer system utilizes a first storage platform;

providing an intermediary computer system, wherein the intermediary computer system utilizes a second storage platform different from and lacking support for synchronization for the first storage platform;

connecting the intermediary computer system to each client computer system;

providing a synchronization adapter to each client computer system enabling the client computer system to logically synchronize with the intermediary computer system;

synchronizing each client computer system with the intermediary computer system via the adapter resident on each client computer system; and

synchronizing each client computer system with the other client computer systems by means of the intermediary computer system;

wherein changes to a first version of a file stored on a client computer system are synchronized to the intermediary computer system to allow a second version of the file stored on a different client computer system to be synchronized with the first version by the intermediary computer system performing the following steps;

receiving a change packet from the client computer system that identifies changes to the first version of the file that were made by the client computer system;

determining whether the first version of the file contains each change that has been synchronized to the intermediary computer system by comparing the identified changes in the change packet with change data associated with the file that is stored on the intermediary computer system such that;

upon determining that the first version of the file contains each change that has been synchronized to the intermediary computer system, the intermediary computer system replaces the change data with the identified changes in the change packet, whereas

upon determining that the first version of the file does not contain each change that has been synchronized to the intermediary computer system, the intermediary computer system generates an exception and does not replace the change data with the identified changes in the change packet.

8. The computer storage medium of claim 7, wherein replacing the change data with the identified changes in the change packet comprises writing the change packet to a packet store on the intermediary computer system, the change packet including the size and last modified date associated with the file.

9. The computer storage medium of claim 8, wherein the change data and the change packet both include a last modified time and size for the file, and wherein comparing the identified changes in the change packet with change data associated with the file comprises:

retrieving a last modified time and size of the file from the change data;

retrieving the last modified time and size of the file from the change packet; and

comparing the last modified time and size from the change data with the last modified time and size from the change packet.

10. The computer storage medium of claim 9, further comprising first read locking the change data and unlocking the change data after retrieving the change data.

11. The computer storage medium of claim 7, further comprising write locking the change data prior to determining whether the first version of the file contains each change that has been synchronized to the intermediary computer system and unlocking the change data after it is replaced or an exception is generated.

12. The computer storage medium of claim 7, receiving a change packet comprises receiving a change packet identifying single instance data.