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

• US 20050060355A1
• Filed: 10/05/2004
• Published: 03/17/2005
• 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 7,293,049 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 an environment that includes a message server storing first message data and a message client storing second message data, a method for enabling synchronization of the second message data with the first message data, while accounting for one or more update notifications that either may or may not have been received by the second device and while accounting for any differences in how the first device and second device store data, the method comprising:

an act of making a change in the first message data, wherein the change is divided into a first portion and at least a second portion, such that the first portion and the at least second portion comprise different portions of the first message data;

an act of sending a first notification to the message client, the first notification including both the first portion of the change and a first token identifying the first portion of the change;

an act of receiving the first token from the message client;

only upon receiving the first token, sending a second notification to the message client, the second notification including both the at least second portion of the change and at least a second token identifying the at least second portion of the change; and

upon failing to receive the first token from the message client, determining that the message client did not receive the first portion of the change associated with the first notification and resending the first notification along with the second notification to the message client.

2. A method as recited in claim 1, wherein the act of resending the change to the message client includes the act of resending the token to the message client.

3. A method as recited in claim 1, wherein the act of sending a notification is performed over an unreliable communication channel.

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

5. A method as recited in claim 3, wherein the acts of receiving a synchronization request and resending the change are performed over a reliable communication channel.

6. A method as recited in claim 1, wherein the token is unique to the message server.

7. A method as recited in claim 1, further comprising the act of compressing the token, wherein the compressed token is unique to the message device.

8. A method as recited in claim 1, wherein the message client comprises one of a portable personal computer, a cellular telephone, a pager, and a personal digital assistant.