05978842 is referenced by 250 patents and cites 21 patents.

A distributed-client change-detection tool detects changes in Internet web-page documents on the world-wide-web. To register a web page for change detection with a change-detection server, a user specifies the web page's URL. A client-side change-detection application is downloaded to the user's client from the change-detection server. The server assigns a date and time for the client to perform change detection. At the assigned time and date, the client fetches a new copy of the web page and compares it to an archived copy to detect changes. When the client detects a change, it sends a notification with the URL to the server. The server verifies that the change has not already been reported by another user's client and then notifies all users of the registered web page. As more users are registered for a web page, change detection is performed more frequently. The most popular pages with tens of thousands of registered users are checked every few minutes. Each user is notified within minutes of any changes in the registered web page, even though any one user only performs change-detection once a month. Checksums rather than entire web pages can be stored and compared to reduce storage requirements at the server. The change-detection server performs its own change-detection for less popular web pages. More popular web pages are checked more frequently using the additional client resources of the users.

Title
Distributed-client change-detection tool with change-detection augmented by multiple clients
Application Number
783625
Publication Number
5978842
Application Date
July 18, 1997
Publication Date
November 2, 1999
Inventor
Matthew P Freivald
Sunnyvale
CA, US
Alan C Noble
Santa Cruz
CA, US
Agent
Stuart T Auvinen
Assignee
NetMind Technologies
CA, US
IPC
H04L 12/00
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