Patent ID: 7613660

Claim:
A method of digital postage mark generation for a mail item, the method comprising the steps of: obtaining a destination address for a mail item; computing a recoverable portion C of the destination address; formatting the recoverable portion C in a cryptographic validation code along with other information of a digital postage mark; sending the digital postage mark to a control computer for formatting and printing; wherein the step of computing the recoverable portion of the destination address includes the steps of: formatting the destination address as an address string of characters; eliminating predetermined words and characters from the address string to form a first string ADDRESSSTRING; counting a number of characters N in ADDRESSSTRING and a number of numeric characters R in ADDRESSSTRING; eliminating all numeric characters from ADDRESSSTRING to obtain a second string ALPHAADDRESSSTRING containing N−R characters; selecting an offset S as a number between 0 and N−R−1, and a number M of recoverable characters; selecting M−R consecutive characters from ALPHAADDRESSSTRING beginning from the character S+1; forming a third string RECOVERABLEPORTION by taking R numeric and M−R alphabetic characters for a total of M selected characters; and formatting RECOVERABLEPORTION into the number C of the plaintext part of postal data of the digital postage mark.