A method and apparatus for accelerating and improving access to network files is provided. One technique for providing data quickly and efficiently is to send a thumbnail of a file to a user rather than sending the entire file. Another technique for providing data quickly and efficiently is to generate the difference between a current version of data and a non-current version of data, to transmit this difference to the requesting user, and to use the difference to update the non-current version of data the user currently has access to. A third technique that can be used in combination with the first two techniques is to compress data, such as the thumbnail or file difference, before transmitting this data. A fourth technique that can be used in combination with the third technique is to securely transmit the compressed data.