DATA TRANSMITTER, DATA RECEIVER, AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To perform device authentication using time without using a high accuracy clock.SOLUTION: A smart meter 3010a comprises: a packet generation unit 301 for generating a data packet; a client clock 4011 for measuring time of the smart meter; a storage unit 305 for storing accuracy information based on accuracy of synchronization with a second clock for measuring time of another device that is to be a transmission destination of the data packet; an authenticator generation unit 302 which calculates first time by adding predetermined time to present time of the smart meter measured by the client clock, calculates second time by modifying the first time by using te accuracy information, and generates an authenticator by using the calculated second time, the data packet, and a predetermined secret key 4001a; and a communication unit 303 for transmitting the data packet to which the authenticator is added to the another device at third time obtained by adding predetermined time to the second time.