04934846 is referenced by 90 patents and cites 19 patents.

A method of franking mail items is disclosed in which the franking impression includes a machine readable portion and a visually readable portion. The machine readable portion comprises a data block including at least a postage charge and a pseudo-random number and the data block is encrypted prior to printing. During printing of the franking impression, at least a part of the machine readable portion is read and compared with the data block intended to be printed. If the comparison is satisfactory the printing operation is continued to print the visually readable portion. The pseudo-random number is changed for each franking transaction which may be each item or batch of items. The machine readable portion is read at a mail handling centre to provide an input to a postage charging and accounting function.

Title
Franking system
Application Number
7/315589
Publication Number
4934846
Application Date
February 27, 1989
Publication Date
June 19, 1990
Inventor
Dennis T Gilham
Brentwood
GB
Agent
Shoemaker and Mattare
Assignee
Alcatel Business Systems
GB
IPC
G06K 9/03
G06F 15/20
G06F 7/38
B41J 5/00
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