Patent ID: 8433826

Claim:
In a network system having a client coupled with a server, a method for serving an image stored in the client to a requesting client, comprising: (a) caching a copy of the image in the server; (b) receiving a request for the image from the requesting client; (c) in response to the server receiving the request from the requesting client for the image stored in the client, sending a request from the server to the client to determine if the image has been modified; (d) if a response from the client indicates that the image has not been modified, transmitting the cached image from the server to the requesting client; (e) if the image has been modified, caching a copy of the modified image on the server, and transmitting the modified image from the server to the requesting client; and (f) synchronizing the server with the client as a background process during image transmission of the cached image between the server and the requesting client, wherein during synchronization, the client uploads a timestamp associated with an image stored on the client.