Patent ID: 6012087
Filing Date: 2000-01-04
Classification: G06F

Abstract:
A change-detection web server for detecting unique changes in web pages comprising:a network connection for transmitting and receiving packets from a remote client and a remote web-page server;a responder, coupled to the network connection, for communicating with the remote client, the responder registering a web page for change detection by receiving from the remote client a uniform-resource-locator (URL) identifying the web page, the responder fetching the web page from the remote web-page server;a database, coupled to the responder, for receiving the URL from the responder when the web page is registered by the remote client, the database for storing a plurality of records each containing a URL;a history table in each of the records in the database, the history table for storing a most-recent signature and a plurality of older-version signatures for a registered web page identified by the URL, the older-version signatures being condensed checksums for earlier versions of the registered web page previously fetched by the change-detection web server, whereas the most-recent signature is a condensed checksum for a most-recently-fetched copy of the registered web page; anda periodic minder, coupled to the database and the network connection, for periodically re-fetching the web page from the remote web-page server by transmitting the URL from the database to the network connection, the periodic minder receiving a fresh copy of the web page from the remote web-page server, the periodic minder generating a new signature from the fresh copy of the web page, the periodic minder notifying the remote client of a unique change when the new signature does not match the most-recent signature and does not match any of the older-version signatures in the record,wherein the unique change in the web page is detected by comparing the new signature to the most-recent signature and to older-version signatures for the web page, wherein changes in the web page which are not unique but match an earlier version of the web page do not notify the remote client.