ANONYMOUS COMMUNICATION METHOD, AUTHENTICATION UNIT, TRANSMITTER, REPEATER, RECEIVER, UNAUTHORIZED PERSON SPECIFYING DEVICE AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To specify an unauthorized user abusing anonymity while sustaining anonymity of an information sender, and to suppress concentration of information to a specific server. SOLUTION: An authentication unit 10 creates a signature creation key for an authorized sender 120-1, and a key certificate including concealed sender information and a signature verification key and issues them to the sender 120-1 in advance thus suppressing concentration of access. The sender 120-1 attaches a digital signature to a message by the signature creation key using a transmitter 20-1 and transmits them, together with the key certificate, to a receiver 40-1 through an anonymous communication path thus guaranteeing anonymity and correctness of the message. In case of an unauthorized sender 120-1, a certification authority 110 specifies the sender 120-1 from the key certificate using the authentication unit 10 thus specifying the unauthorized sender 120-1. COPYRIGHT: (C)2006,JPO&NCIPI