Client store synchronization through intermediary store change packets

• US 20050246389A1
• Filed: 04/20/2005
• Published: 11/03/2005
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Novik, Lev, Pohlmann, Nils H., Thomas, Michael W., Mahajan, Sameer S., Maksimenka, Andrei, Shah, Darshatkumar A.
• Granted Patent: US 7,778,962 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 data synchronization system comprising:

an intermediary storage system; and

an interface component associated with one or more sync client systems comprising a conflict detection component, the interface component facilitates synchronization of at least a portion of a client system data store through an intermediary storage system data store, the conflict detection component detects and prevents application of any conflicting entities or changes thereof to the intermediary data store.

2. The system of claim 1, the conflict detection component comprises:

a state input component that retrieves change knowledge from an entity on a client system and a corresponding entity on the intermediary storage system; and

a comparison component that compares the knowledge of each entity and generates a conflict signal that prevents synchronization if the intermediary storage system entity knowledge is greater than the client system entity knowledge.

3. The system of claim 2, the interface component further comprising a conflict resolution component that resolves a detected conflict automatically in accordance with, a conflict resolution policy.

4. The system of claim 1, the interface component further comprising a data integrity component that facilitates storage of entries to the intermediary store in a manner that preserves data and ensures a consistent state on the intermediary store.

5. The system of claim 1, the interface component further comprising:

a data monitor component that monitors designated data on the client system; and

a generation component that generates a change data packet that is transmitted between the client system and the intermediary storage system.

6. The system of claim 5, a change packet includes a change data attribute, a prerequisite knowledge attribute, and a learned knowledge attribute.

7. The system of claim 6, the change data specifies changes to be made to an item.

8. The system of claim 6, the change data includes a single instance of a data entity.

9. The system of claim 6, the interface component further comprises:

a package receiver component that receives a change packet and indicates whether the data change attribute references single instance data;

an entry retriever component that retrieves the referenced single instance data; and

an output component that serializes the data to the intermediary store.

10. A method for synchronizing data comprising:

detecting a data entity change;

generating a change data packet including change data and prerequisite knowledge; and

transmitting the change packet to an intermediary storage system.

11. The method of claim 10, further comprising copying the entire changed data entity to the intermediary storage system.

12. A computer readable medium having stored thereon computer executable instructions for carrying out the method of claim 10.

13. A change packet store and client store interaction methodology comprising:

receiving a change packet from an client data store identifying at least a modified data entity;

determining the prerequisite knowledge of the data entity presently stored on a change packet store; and

replacing the entity presently on the packet store with the modified data entity, if it includes at least the prerequisite knowledge of the presently stored item.

14. The method of claim 13, further comprising writing the change packet to the packet store, the packet including the size and last modified date associated with the modified data entity.

15. The method of claim 14, further comprising:

retrieving a last modified time and size of the entity from the entity;

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

retrieving the entity and updating a client store therewith if the retrieved last modified time and size from the entity and an associated change packet is the same.

16. The method of claim 15, further comprising first read locking the entity and unlocking the entity after retrieving the file.

17. The method of claim 13, further comprising write locking the data item prior to determining the knowledge associated therewith and unlocking the entity after it is replaced or a knowledge exception is generated.

18. The method of claim 13, receiving a change packet comprises receiving a change packet identifying single instance data.

19. The method of claim 13, further comprising setting the prerequisite knowledge associated with the modified entity to zero.

20. A computer readable medium having stored thereon computer executable instructions for carrying out the method of claim 13.