EDWARD W STERLING
Broker in Bolton, MA

5086402, Feb 4, 1992

May 30, 1990

7/528339

Edward W. Sterling - Bolton MA

Simware, Inc. - Nepean

G06K 1500, H04L 1100

364514

The method of this invention comprises an efficient technique for transfer of information over a communication link between first and second processors, the processors employing blocks of data on a repetitive basis. Each processor includes means for storing copies of used blocks of data. A block of data currently used (or displayed) in the second processor is called an "old" data block and a block of data to be transmitted from the first processor to the second processor is called "new" data block. The method includes the steps of storing identical copies of used data blocks and the old data block in the memories of the first and second processors. The new data block is then compared in the first processor to stored data block copies to determine if the new data block equals a pre-established level of similarity with any of the stored data block copies. If a stored data block is found to equal the pre-established level of similarity with the new data block, the method contemplates transmission to the second processor of information regarding the differences between the new data block and the similar stored data block, as well as the identity of the similar stored data block. The second processor then proceeds to access its copy of the identified similar stored data block and to alter that data block in accordance with the difference information transmitted from the first processor.