Method and system for fair exchange of user information

A system for exchanging user information over a network comprising:

• at least one programmed processor coupled to a memory and arranged for conducting a fair exchange of 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;
• 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 modular 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 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.