04637051 is referenced by 159 patents and cites 17 patents.

A system for the metering of encrypted postage and similar indicia includes a device for printing such indicia and a device for reading such indicia. The printing is accomplished with a dot matrix printer driven by signals obtained from a character generator and an encryption circuit. The reading is accomplished by correlating received characters against a stored array of symbols to determine the presence of a symbol and the comparison of the separated coded data with a reference code to determine the accuracy of the printed material. Thereby, forgery and alteration is inhibited. Alphanumeric characters are utilized for both the data and the code, a group of characters for the data being separated from a group of characters for the code to allow for the reading of the data, while readily extracting the remaining characters for verification purposes.

Title
System having a character generator for printing encrypted messages
Application Number
6/515073
Publication Number
4637051
Application Date
July 18, 1983
Publication Date
January 13, 1987
Inventor
John I Clark
Milford
CT, US
Agent
William D Soltow Jr
Albert W Scribner
David E Pitchenik
Assignee
Pitney Bowes
CT, US
IPC
G06H 9/00
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