Abstract: A time authority is established within a trusted time authority hierarchy which is periodically updated with the current date and time by the time authority. The user trusts the time authority and the associated hierarchy. Servers in the chain of the established authority are authorized to stamp a message with the time and date and encode the message so the recipient knows whether the message has been tampered with since the date stamp was attached. Existing browser security features are used to provide the tamper-proof mechanism. Messages are sent to trusted outgoing mail servers and are time stamped, encoded with the time authority's digital signature for tamper protection, and are also encrypted according to the user's preferences. The message is then routed to the intended recipient whose mail reader receives the message, decodes the time authority's digital signature for tamper detection, and decrypts the message if it has been encrypted.

Abstract: A method and system for removing duplicate query results in a database system comprising a plurality of data sources. The method and system includes issuing a query from a user to a first data source. In response to receiving a first query result from the data source, a first hash index is computed for the first query result and the first query result is passed on to the user. The method and system further includes receiving a second query result and computing a second hash index for the second query result. The first hash index is then compared with the second hash index to cheek for a hash collision. If the first, and second hash indexes match, the first data source is queried for data corresponding to the second query result. And if the first data source contains the data, then the second query result is considered a duplicate and is discarded.

Abstract: A sprite engine or compositor that is well-adapted to a variety ofadaptable to a host platforms and that minimizes the amount of drawing that occurs on a refresh of a framebuffer display area. The invention exploits the host platform's abilities to perform both back-to-front and front-to-back drawing algorithms, where the choice of algorithm used depends upon whether a sprite is opaque or transparent. Each sprite registers itself with a sprite engine, identifying whether or not the sprite is wholly opaque or notis transparent, the bounding area of the sprite, and the function that the sprite uses to draw. The function can be the drawing routine that is available from the host platform or operating system. The sprite engine keeps track of the Z position of each sprite and examines each sprite to determine if the sprite overlaps a particular region that needs to be refreshed.