Systems and methods for providing conflict handling for peer-to-peer synchronization of units of information manageable by a hardware/software interface system

• US 20050044187A1
• Filed: 06/30/2004
• Published: 02/24/2005
• Est. Priority Date: 08/21/2003
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Novik, Lev, Shah, Ashish, Hudis, Irena, Jhaveri, Vivek Jawahir
• Granted Patent: US 7,512,638 B2
• Time in Patent Office: Days
• US Class Current: 709/219
• CPC Class Codes: G06F 16/1834 implemented based on peer-to-peer networks, e.g. gnutella p2p communication protocols H04L67/104
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/30 Profiles
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: Y10S 707/99942 Manipulating data structure, e.g. compression, compaction, compilation
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users

Abstract

Various embodiments of the present invention are directed to conflict handling for conflicts that occur in a peer-to-peer synchronization system, where the ability to correctly and efficiently handle conflicts minimizes data loss while retaining good usability and reduces the need for user intervention during synchronization. Conflict handling in the synchronization service is divided into three stages: (1) conflict detection; (2) automatic conflict resolution and logging; and (3) conflict inspection and resolution. Certain embodiments are directed to a conflict handling schema comprising one or more of the follow conflict handling elements: (a) schematized representation of conflicts; (b) detection of conflicts; (c) logging of conflicts into a durable store; (d) automatic resolution of conflicts according to a flexible and configurable azqsxqxwdconflict resolution policy; (e) composable and extensible conflict handlers to filter and resolve conflicts; (f) automatic detection and removal of obsolete conflicts; and (g) programmatic conflict resolutions.

Claims

1. A method for handling conflicts in a peer-to-peer synchronization system, said method comprising identifying a conflict and representing said conflict as a unit of data storable in a data store (an “

item”

) for resolution of said conflict by said peer-to-peer synchronization system.

2. The method of claim 1 further comprising:

for certain conflicts, logging said conflict item in a durable data store for later resolution of said conflict by said peer-to-peer synchronization system; and

for certain conflicts, automatically resolving said conflict according to a conflict resolution policy specifying at least one specific conflict handler, said conflict hander being one of a group of conflict handlers comprising the following types of conflict handlers;

a filter, and a resolver.

3. The method of claim 2 wherein:

said conflict handler is an item and is extensible; and

said group of conflict handlers is composable and extensible.

4. The method of claim 3 wherein said conflict resolution policy specifies at least two conflict handlers comprising a conflicting handling pipeline.

5. The method of claim 2 further comprising the automatic detection and removal of an obsolete conflict, including but not limited to the removal of an obsolete conflict item in the data store.

6. The method of claim 1 wherein said conflict item, when logged to a durable data store, comprises a copy of the target item to which a change giving rise to said conflict applies

7. The method of claim 6 wherein said copy of said target item reflects the change giving rise to said conflict.

8. The method of claim 1 further comprising logging a first conflict item pertaining to a specific change unit into a durable data store for later resolution of said first conflict by said peer-to-peer synchronization system, said conflict item comprising a change awareness, and said logging said conflict item in said durable data store, said logging comprising:

searching the durable data store and determining if there is a preexisting conflict item already present for the same specific change unit as the first conflict item;

if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item, removing the preexisting conflict item if its change awareness is subsumed by the change awareness of the first conflict item;

if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item, removing the first conflict item if its change awareness is subsumed by the change awareness of the preexisting conflict item; and

if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item, and if the change awareness of the first conflict item is not subsumed by the change awareness of the preexisting conflict item, and if the change awareness of the preexising conflict item is not subsumed by the change awareness of the first conflict item, then retaining the preexisting conflict item in the and adding the first conflict item to the durable data store.

9. A system for handling conflicts in a peer-to-peer synchronization system, said system comprising:

a subsystem for identifying a conflict;

a subsystem for representing said conflict as a unit of data storable in a data store (an “

item”

); and

a subsystem for resolving said conflict.

10. The system of claim 9 further comprising:

a subsystem for logging said conflict item in a durable data store for later resolution of said conflict by said peer-to-peer synchronization system; and

a subsystem for automatically resolving said conflict according to a conflict resolution policy specifying at least one specific conflict handler, said conflict hander being one of a group of conflict handlers comprising the following types of conflict handlers;

a filter, and a resolver.

11. The system of claim 10 further comprising:

an extensible conflict handler; and

a composable and extensible group of conflict handlers.

12. The system of claim 11 further comprising a conflict handling pipeline, said conflict handling pipeline comprising at least two conflict handlers.

13. The system of claim 10 further comprising a subsystem for the automatic detection and removal of an obsolete conflict, including but not limited to the removal of an obsolete conflict item in the data store.

14. The system of claim 9 further comprising a subsystem for making a copy of a target item to which a change giving rise to a conflict applies and storing said copy in conjunction with a conflict item in a conflict log maintained on a durable data store.

15. The system of claim 14 further comprising a subsystem to modify said copy of said target item to reflect the change giving rise to said conflict.

16. The system of claim 9 further comprising a subsystem for logging a first conflict item pertaining to a specific change unit into a durable data store for later resolution of said first conflict by said peer-to-peer synchronization system, said conflict item comprising a change awareness, and said logging said conflict item in said durable data store, said subsystem further comprising:

a subsystem for searching the durable data store and determining if there is a preexisting conflict item already present for the same specific change unit as the first conflict item;

a subsystem for removing the preexisting conflict item if its change awareness is subsumed by the change awareness of the first conflict item if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item;

a subsystem for removing the first conflict item if its change awareness is subsumed by the change awareness of the preexisting conflict item if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item; and

a subsystem for retaining the preexisting conflict item in the and adding the first conflict item to the durable data store if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item, and if the change awareness of the first conflict item is not subsumed by the change awareness of the preexisting conflict item, and if the change awareness of the preexising conflict item is not subsumed by the change awareness of the first conflict item.

17. A computer-readable medium comprising computer-readable instructions for handling conflicts in a peer-to-peer synchronization system, said computer-readable instructions comprising instructions for identifying a conflict and representing said conflict as a unit of data storable in a data store (an “

item”

) for resolution of said conflict by said peer-to-peer synchronization system.

18. The computer-readable instructions of claim 17 further comprising instructions for:

logging said conflict item in a durable data store for later resolution of said conflict by said peer-to-peer synchronization system; and

automatically resolving said conflict according to a conflict resolution policy specifying at least one specific conflict handler, said conflict hander being one of a group of conflict handlers comprising the following types of conflict handlers;

a filter, and a resolver.

19. The computer-readable instructions of claim 18 further comprising instructions whereby:

said conflict handler is an item and is extensible; and

said group of conflict handlers is composable and extensible.

20. The computer-readable instructions of claim 19 further comprising instructions whereby said conflict resolution policy specifies at least two conflict handlers comprising a conflicting handling pipeline.

21. The computer-readable instructions of claim 18 further comprising instructions whereby the automatic detection and removal of an obsolete conflict, including but not limited to the removal of an obsolete conflict item in the data store.

22. The computer-readable instructions of claim 17 further comprising instructions whereby said conflict item, when logged to a durable data store, comprises a copy of the target item to which a change giving rise to said conflict applies.

23. The computer-readable instructions of claim 22 further comprising instructions whereby said copy of said target item reflects the change giving rise to said conflict.

24. The computer-readable instructions of claim 17 further comprising instructions for logging a first conflict item pertaining to a specific change unit into a durable data store for later resolution of said first conflict by said peer-to-peer synchronization system, said conflict item comprising a change awareness, and said logging said conflict item in said durable data store, said logging instructions further comprising instructions for:

searching the durable data store and determining if there is a preexisting conflict item already present for the same specific change unit as the first conflict item;

removing the preexisting conflict item if its change awareness is subsumed by the change awareness of the first conflict item if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item;

removing the first conflict item if its change awareness is subsumed by the change awareness of the preexisting conflict item if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item; and

retaining the preexisting conflict item in the and adding the first conflict item to the durable data store if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item, and if the change awareness of the first conflict item is not subsumed by the change awareness of the preexisting conflict item, and if the change awareness of the preexising conflict item is not subsumed by the change awareness of the first conflict item.

25. A hardware control device for handling conflicts in a peer-to-peer synchronization system, said device comprising:

means identifying a conflict; and

means for representing said conflict as a unit of data storable in a data store (an “

item”

) for resolution of said conflict by said peer-to-peer synchronization system.

26. The hardware control device of claim 25 further comprising:

means of, for certain conflicts, logging said conflict item in a durable data store for later resolution of said conflict by said peer-to-peer synchronization system; and

means of, for certain conflicts, automatically resolving said conflict according to a conflict resolution policy specifying at least one specific conflict handler, said conflict hander being one of a group of conflict handlers comprising the following types of conflict handlers;

a filter, and a resolver.

27. The hardware control device of claim 26 further comprising:

means for said conflict handler to be an extensible item; and

means for said group of conflict handlers to be both composable and extensible.

28. The hardware control device of claim 27 further comprising means whereby said conflict resolution policy specifies at least two conflict handlers comprising a conflicting handling pipeline.

29. The hardware control device of claim 26 further comprising means whereby the automatic detection and removal of an obsolete conflict, including but not limited to the removal of an obsolete conflict item in the data store.

30. The hardware control device of claim 25 further comprising means whereby said conflict item, when logged to a durable data store, comprises a copy of the target item to which a change giving rise to said conflict applies

31. The hardware control device of claim 30 further comprising means whereby said copy of said target item reflects the change giving rise to said conflict.

32. The hardware control device of claim 25 further comprising means for logging a first conflict item pertaining to a specific change unit into a durable data store for later resolution of said first conflict by said peer-to-peer synchronization system, said conflict item comprising a change awareness, and said logging said conflict item in said durable data store, said logging comprising:

meanas for searching the durable data store and determining if there is a preexisting conflict item already present for the same specific change unit as the first conflict item;

means for, if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item, removing the preexisting conflict item if its change awareness is subsumed by the change awareness of the first conflict item;

means for, if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item, removing the first conflict item if its change awareness is subsumed by the change awareness of the preexisting conflict item; and

means for, if there is a preexisting conflict item already present in the durable data store for the same specific change unit as the first conflict item, and if the change awareness of the first conflict item is not subsumed by the change awareness of the preexisting conflict item, and if the change awareness of the preexising conflict item is not subsumed by the change awareness of the first conflict item, then retaining the preexisting conflict item in the and adding the first conflict item to the durable data store.