Accounting for update notifications in synchronizing data that may be represented by different data structures

• US 20050050104A1
• Filed: 10/08/2004
• Published: 03/03/2005
• Est. Priority Date: 01/24/2001
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Fishman, Neil S., Seinfeld, Marc E., Kadyk, Donald J.
• Granted Patent: US 7,293,045 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/273 Asynchronous replication or reconciliation
• CPC Class Codes: G06F 9/542 Event management; Broadcasting; Multicasting; Notifications
• CPC Class Codes: G06F 9/546 Message passing systems or structures, e.g. queues
• CPC Class Codes: H04L 67/01 Protocols
• 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: Y10S 707/922 Communications
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99954 Version management
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

Methods, systems, and computer program products for synchronizing data stored at one or more message clients with data stored at a message server where the message clients may receive update notifications and may represent the data using different data structures than the message server uses to represent the same data. A token is associated with each data change that occurs at the message server. The message server sends each change and associated token to the message clients. When the message clients request a synchronization, the tokens they received are returned to the message server for comparison with the tokens the message server sent to the message clients. If the message clients do not return a particular token, the message server determines that the clients did not receive the corresponding change and resends the change to the message clients. Tokens may also be used to divide a change into one or more portions, with only one portion being provided initially. Then, in response to receiving the token associated with the portion, the message server may provide the remaining portion of the message to the message clients.

Claims

1. In a computing environment that includes a server and one or more clients, a method for enabling synchronization of data stored at the one or more clients with data stored at the server, while accounting for one or more update notifications that either may or may not have been received by the one or more clients and while accounting for any differences in how the server and the one or more clients store data, the method implemented in one of the clients comprising:

an act of receiving a plurality of update notifications, corresponding to changes made at a server to server data, the notifications being received by the client from the server over an unreliable communication channel without including any request for acknowledgement of receipt of the update notifications by the client, each update notification including (i) at least one of the plurality the changes and (ii) a plurality of tokens, at least one of the plurality of tokens corresponding to the at least one of the plurality of changes;

an act of the client sending a plurality of tokens back to the server, wherein the server interprets one or more tokens that were sent to the client but that were not received back from the client as indications that one or more changes are missing from the client; and

an act of the client receiving a list of one or more missing tokens, the list identifying one or more tokens that were sent to the client but that were not received by the server from the client;

sending a request to the server to resend the one or more missing tokens and corresponding changes; and

an act of receiving the one or more missing tokens and corresponding changes to the one or more requesting clients.

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

an act of receiving a collection object from the server comprising a list of tokens, the list representing a state of the data stored at the client.

3. A method as recited in claim 1, wherein the unreliable communication channel comprises a wireless communication channel.

4. A method as recited in claim 1, wherein the plurality of tokens are compressed such that the compressed plurality of tokens are unique to the client.

5. A method as recited in claim 1, wherein the data stored at the server includes at least one of contact data, calendar data, task data, and email data.

6. A method as recited in claim 1, wherein and wherein the one or more clients comprise one of a portable personal computer, a cellular telephone, a pager, and a personal digital assistant.

7. A method as recited in claim 1, wherein at least one change made in the server data is divided into a first portion and a second portion, and at least one notification corresponds to the first portion, the method further comprising:

an act of the client sending back a token associated with the first portion; and

an act of receiving the second portion at the client in response to sending back the token associated with the first portion.

8. In an electronic messaging environment that includes a message server and one or more message clients, a method for enabling synchronization of data stored at the one or more message clients with data stored at the message server, while accounting for one or more update notifications that either may or may not have been received by the one or more message clients and while accounting for any differences in how the message server and the one or more message clients store data, the method implemented in one of the clients comprising:

the client receiving, over an unreliable communication channel, a plurality of notifications without sending acknowledgement of receipt of the notifications, the plurality of notifications including (i) a plurality of changes to data stored at a message server, and (ii) a plurality of tokens identifying each of the plurality of changes;

an act of receiving a list identifying missing notifications, wherein the missing notifications are determined by the server to be missing based on whether or not the client sends back each of the plurality of tokens identifying each of the plurality of changes to the server;

sending a request to the server to resend the one or more missing notifications; and

an act of receiving the one or more missing notifications.

9. A method as recited in claim 8, wherein the unreliable communication channel comprises a wireless communication channel.

10. A method as recited in claim 8, further comprising:

receiving a collection object to the one or more message clients, the collection object representing a state of the data stored at the client.

11. A method as recited in claim 8, wherein the plurality of tokens are compressed such that the compressed plurality of tokens are unique to the client.

12. A method as recited in claim 8, wherein the data stored at the server includes at least one of contact data, calendar data, task data, and email data.

13. A method as recited in claim 8, wherein and wherein the one or more clients comprise one of a portable personal computer, a cellular telephone, a pager, and a personal digital assistant.

14. A method as recited in claim 8, wherein at least one change made in the server data is divided into a first portion and a second portion, and at least one notification corresponds to the first portion, the method further comprising:

an act of the client sending back a token associated with the first portion; and

an act of receiving the second portion at the client in response to sending back the token associated with the first portion.

22. A computer program product comprising one or more computer-readable media having computer-executable instructions for implementing the method recited in claim 8.

15. A computer program product for use in a computing environment that includes a server and one or more clients, the computer program product comprising one or more computer-readable media having computer-executable instructions for implementing a method for enabling synchronization of data stored at the one or more clients with data stored at the server, while accounting for one or more update notifications that either may or may not have been received by the one or more clients and while accounting for any differences in how the server and the one or more clients store data, the method implemented in one of the clients comprising:

an act of receiving a plurality of update notifications, corresponding to changes made at a server to server data, the notifications being received by the client from the server over an unreliable communication channel without including any request for acknowledgement of receipt of the update notifications by the client, each update notification including (i) at least one of the plurality the changes and (ii) a plurality of tokens, at least one of the plurality of tokens corresponding to the at least one of the plurality of changes;

an act of the client sending a plurality of tokens back to the server, wherein the server interprets one or more tokens that were sent to the client but that were not received back from the client as indications that one or more changes are missing from the client; and

an act of the client receiving a list of one or more missing tokens, the list identifying one or more tokens that were sent to the client but that were not received by the server from the client;

sending a request to the server to resend the one or more missing tokens and corresponding changes; and

an act of receiving the one or more missing tokens and corresponding changes to the one or more requesting clients.

16. A computer program product as recited in claim 15, wherein the method further comprises:

an act of receiving a collection object from the server comprising a list of tokens, the list representing a state of the data stored at the client.

17. A computer program product as recited in claim 15, wherein the unreliable communication channel comprises a wireless communication channel.

18. A computer program product as recited in claim 15, wherein the plurality of tokens are compressed such that the compressed plurality of tokens are unique to the client.

19. A computer program product as recited in claim 15, wherein the data stored at the server includes at least one of contact data, calendar data, task data, and email data.

20. A computer program product as recited in claim 15, wherein and wherein the one or more clients comprise one of a portable personal computer, a cellular telephone, a pager, and a personal digital assistant.

21. A computer program product as recited in claim 15, wherein at least one change made in the server data is divided into a first portion and a second portion, and at least one notification corresponds to the first portion, the method further comprising:

an act of the client sending back a token associated with the first portion; and

an act of receiving the second portion at the client in response to sending back the token associated with the first portion.