System and method for synchronizing objects between two devices

• US 6,862,617 B1
• Filed: 06/04/1999
• Issued: 03/01/2005
• Est. Priority Date: 10/12/1998
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Wu, Charles
• Primary Examiner(s): Donaghue, Larry D.
• Application Number:
  US09/326,163
• Time in Patent Office: 2,097 Days
• Field of Search: 709220-223, 709/217, 709/219, 709/224, 709/225, 707/10, 707/201, 707/203
• US Class Current: 709/224
• CPC Class Codes: G06F 16/275 Synchronous replication
• 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 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users

Abstract

A synchronization system synchronizes objects between a portable computer and a desktop computer. The portable computer is capable of communicating with a storage volume that can become inaccessible to the portable computer. The system identifies storage volumes currently available to the portable computer and identifies storage volumes previously accessible to the portable computer, but not currently accessible to the portable computer. Objects contained in storage volumes that are currently accessible to the portable computer are then synchronized between the base computer and the portable computer. During the synchronization process, the system ignores objects stored on volumes that are not currently accessible to the portable computer. However, the system continues to monitor and record changes to objects stored on volumes that are not currently accessible to the portable computer. When a storage volume that was previously inaccessible becomes accessible, the system synchronizes objects stored on the previously inaccessible storage volume. The objects may be databases or other data structures. The storage volume that can become inaccessible to the portable computer is typically a removable memory card that can be inserted into the portable computer.

Claims

1. A method comprising:

without input from a user, automatically identifying storage volumes currently accessible to a first device, wherein the storage volumes store objects;

based on the identification of storage volumes currently accessible to the first device, automatically identifying objects subject to deletion from a second device during a synchronization process to occur between the first device and the second device;

without input from a user, automatically preventing deletion of the objects subject to deletion during the synchronization process; and

automatically synchronizing only objects contained in the storage volumes currently accessible to the first device.

2. A method as recited in claim 1, wherein the automatic preventing includes identifying storage volumes as previously accessible to the first device but not currently accessible to the first device and while synchronizing, automatically ignoring objects stored on the second device corresponding to objects on storage volumes previously accessible to the first device but not currently accessible to the first device.

3. A method as recited in claim 1, wherein each object comprises a plurality of data items, and wherein the synchronizing step further comprises synchronizing data items in one object with corresponding data items in another object.

4. A method as recited in claim 1, wherein the objects are databases.

5. A method as recited in claim 1, wherein the first device identifies storage volumes currently accessible to the first device.

6. A method as recited in claim 1, wherein the storage volume that can become inaccessible to the first device is a removable memory card configured to be inserted into the first device.

7. A method as recited in claim 1, wherein the first device is a portable computing device.

8. A method as recited in claim 1, wherein the second device is a desktop computer.

9. A method as recited in claim 1, further comprising:

the second device continuing to monitor and record changes to objects stored on the second device that are inaccessible to the first device.

10. A method as recited in claim 1 further comprising:

when a storage volume that was previously inaccessible becomes accessible, synchronizing objects stored on the previously inaccessible storage volume.

11. One or more computer-readable memories containing a computer program that is executable by a processor to perform the method recited in claim 1.

12. A method of synchronizing objects between a portable computer and a base computer, wherein the base computer attempts to delete objects during synchronization if corresponding objects are not accessible to the portable computer, the method comprising:

storing an object on a removable storage device, wherein the removable storage device is configured to be inserted into and removed from the portable computer;

automatically creating an association between the object and a corresponding object on the base computer; and

without user intervention, synchronizing the object stored on the removable storage device with the corresponding object on the base computer if the removable storage device is inserted into the portable computer; and

without user intervention, automatically preventing the corresponding object on the base computer from being deleted if the removable storage device is not inserted into the portable computer.

13. A method as recited in claim 12, wherein the object comprises a plurality of data items and the corresponding object on the base computer comprises a plurality of corresponding data items.

14. A method as recited in claim 12, wherein the object comprises a plurality of data item and the corresponding object on the base computer comprises a plurality of corresponding data items, and wherein synchronizing the object further comprises synchronizing data items in the object with the corresponding data items in the corresponding object on the base computer.

15. A method as recited in claim 12, wherein the portable computer determines whether the removable storage device is inserted into the portable computer.

16. A method as recited in claim 12, further comprising:

the base computer continuing to monitor and record changes to the object when the removable storage device is not inserted into the portable computer; and

when the removable storage device that was previously inaccessible to the portable computer becomes accessible, immediately synchronizing objects stored on the removable storage device without user intervention.

17. One or more computer-readable memories containing a computer program that is executable by a processor to perform the method recited in claim 12.

18. A method of synchronizing objects between a portable computer and a base computer, wherein during synchronization the base computer tries to delete objects on the base computer if corresponding objects are not accessible to the portable computer, the method comprising:

automatically identifying storage volumes currently accessible to the portable computer, wherein each storage volume contains at least one object and wherein each object contains a plurality of data items; and

automatically synchronizing only objects contained in storage volumes that are currently accessible to the portable computer; and

without user intervention, automatically preventing deletion of objects on the base computer in response to corresponding objects being inaccessible to the portable computer.

19. A method as recited in claim 18, further comprising:

identifying storage volumes previously accessible to the portable computer but not currently accessible to the portable computer.

20. A method as recited in claim 18, further comprising:

identifying storage volumes previously accessible to the potable computer but not currently accessible to the portable computer; and

while synchronizing, ignoring objects stored on storage volumes that are not currently accessible to the portable computer.

21. A method as recited in claim 18, wherein the portable computer is capable of communicating with a removable memory card configured to be inserted into the portable computer.

22. A method as recited in claim 18, further comprising:

the base computer continuing to monitor and record changes to objects stored on storage volumes that are inaccessible to the portable computer; and

in response to a storage volume that was previously inaccessible to the portable computer becoming accessible, automatically synchronizing objects stored on the storage volume.

23. One or more computer-readable memories containing a computer program that is executable by a processor to perform the method recited in claim 18.

24. In a system using a synchronization process between a first device and a second device in which the first device is capable of communicating with a storage volume that can become inaccessible to the first device and wherein the second device tries to delete objects on the second device that are not accessible on the first device, one or more computer-readable media having stored thereon a computer program comprising the following steps:

identifying storage volumes currently accessible to the first device;

identifying removable storage volumes previously accessible to the first device but not currently accessible to the first device;

without user intervention, automatically preventing deletion of objects corresponding to objects on previously accessible storage volumes; and

synchronizing only objects contained in storage volumes that are currently accessible to the first device.

25. One or more computer-readable media as recited in claim 24 further comprising:

during a synchronization process, ignoring objects stored on removable storage volumes that were previously accessible to the first device but are not currently accessible to the first device.

26. One or more computer-readable media as recited in claim 24, wherein the removable storage volumes that are not currently accessible to the first device are removable memory cards configured to be inserted into the first device.

27. One or more computer-readable media as recited in claim 24 further comprising:

continuing to monitor and record changes to objects stored on removable storage volumes that were previously accessible to the first device but are not currently accessible to the first device.

28. In a system that tries to delete objects during synchronization if the objects are not accessible to a peripheral computer, an apparatus comprising:

a communications module;

a data store that contains a list of accessible storage volumes and inaccessible storage volumes of a peripheral computer; and

a desktop synchronization manager coupled to the communications module and the data store, wherein the desktop synchronization manager is configured to automatically synchronize, without user intervention, only objects stored on accessible storage volumes of the peripheral computer and to automatically prevent deletion of objects associated with storage volumes inaccessible to the peripheral computer.

29. An apparatus as recited in claim 28 wherein the inaccessible storage volumes are removable memory cards configured to be inserted into the apparatus.

30. An apparatus as recited in claim 28 wherein the apparatus is desktop computer.

31. An apparatus as recited in claim 28 wherein the desktop synchronization manager is configured to continue monitoring and recording changes to objects stored on inaccessible storage volumes.

32. An apparatus as recited in claim 28 wherein the desktop synchronization manager is configured to continue monitoring and recording changes to objects stored on inaccessible storage volumes, and wherein the desktop synchronization manager is further configured to synchronize objects stored on inaccessible storage volumes after an inaccessible storage volume becomes accessible.