Patent ID: 7412055

Claim:
A method fairly exchanging a hidden value of a first user for a hidden value of a second user, by a series of exchanges between the first user and the second user leading up to completing said hidden values, comprising the steps of: establishing a modulus and a modular function known to the first user and known to the second user, said modular function iteratively producing a plurality of sequence values wherein each said sequence value is related, according to said modular function, to a next previous sequence value, whereby conformance to the modulation function can be determined for adjacent ones of the plurality of sequence values; establishing a total number of iterations over which the sequence values will be exchanged between the first user and the second user; iteratively exchanging the sequence values of the first and second users, progressing in a predetermined order toward an end of said sequence values; completing the exchange provided that the total number of iterations are completed, and terminating the exchange if the total number of iterations are not completed.