ELECTRONIC VALUE EXCHANGING METHOD, USER DEVICE, AND THIRD PERSON DEVICE

摘要

PROBLEM TO BE SOLVED: To improve efficiency in processing for fairness guarantee in electronic value exchange so as to be appropriate.;SOLUTION: A user device 2 generates electronic signature Sab for information including second session information s2 included in agreement information and information Mab showing a stop request by using only the second session information instead of the agreement information (S202), and outputs stop request information Rab including the session information s2 and the information Mab showing the stop request and the electronic signature Sab (S203). Thus, it is possible to attain transmission/reception by omitting any unnecessary information. In the same way, the electronic signature for information including the session information s2 and information showing a completion request can be generated by using only the second session information s2, and the completion request information including the electronic signature can be outputted. A third person device 3 defines a third session state in association with the second session information s2 as stop (S206). Thus, it is possible to appropriately discriminate exchanges of a simultaneous parallel plurality of electronic values and state management can be carried out.;COPYRIGHT: (C)2006,JPO&NCIPI