Patent ID: 6499019
Filing Date: 2002-12-24
Classification: G06Q,H04L

Abstract:
An electronic payment device using an unbalanced binary tree for using in a computer of an electronic payment system so as to calculate a first data Xk of current consumption, or calculate a plurality of contrast values Mq, after said first data Xk and said contrast values Mq being sent to a merchant computer through a network, said merchant computer performing a reprocess procedure for said first data Xk to form with a second data Xâ€²k, and checking whether said respective contrast value Mq is equal to said second data Xâ€²k, so as to determine whether this transaction is successful, said electronic payment device primarily comprising:a data providing means for providing datum including the total unit n of the amount of money that user purchases, a first one-way function h1, a second one-way function h2, and the current unit k of the amount of money after current consumption; a first processing means for selecting two positive integers p and q which conforming the relation pÃ—q=n; a random number generator for generating a random number and setting said random number as an initial value Xpq; a second processing means for calculating the number a of times of said first one-way function h1 by formula a=q-&LeftCeiling;kp&RightCeiling;,â€ƒaccording to said two positive integers p and q and said current unit k of the amount of money after current consumption, where &LeftCeiling;kp&RightCeiling;â€ƒrepresents that said value k dividing by p is carried by one in any condition; a third processing means for calculating the number b of times of said second one-way function h2 by formula b=[pâˆ’(k mod p)] mod p, according to said positive integer p and said current unit k of the amount of money after current consumption, where (k mod p) represents the residue of k dividing by p; and a fourth processing means for calculating said first data Xk by formula Xk=h2b(h1a(Xpq)), according to said numbers of times a and b, said first one-way function h1, said second one-way function h2, and said initial value Xpq, where h1a(Xpq) represents that said value Xpq is operated by said first one-way function h1 for a times, where h2b(h1a(Xpq)) represents that said value h1a(Xpq) is operated by said second one-way function h2 for b times.