Universal Electronic Cash

This papcr proposcs the first idcal untraccablc elcctronic cash systcm whicli solves the most crucial problem inherent with real cash and all previous tintraceable clcctronic cash systems. The main advantage of the new systcm is that thc customcr can subdivide his cash balance, C (dollars), into many pieccs in any way hc plcases until thc total value of all subtli\kied piccc cquals C. This systcm can bc irnplcmciited cficicntly. In a typical implrnicntation, the data sizc of one pice of clcctronic cash is less than 100 bytes regardlesb of thc face value of piccc, the computation time for cach transaction is scvcral seconds, assuming the existcncc of a Rabin sclicrne cliip. The sccurity of this sclicnic rclies on the difIiciilty of factoring.