COMMUNICATION APPARATUS, COMMUNICATION SYSTEM AND COMMUNICATION METHOD

摘要

PROBLEM TO BE SOLVED: To perform communication by a secure frame even when a security key (key) concerned with secure communication is changed.SOLUTION: A communication apparatus for receiving a secure frame to which at least a transmission frame counter value is given from one or more other communication apparatuses managing transmission frame counter values indicating the number of times of transmission of secure frames using the key concerned with secure communication includes receiving frame counter storage means which stores the transmission frame counter value given to the secure frame received from any one of one or more other communication apparatuses as the receiving frame counter value of the other concerned communication apparatus and individually stores receiving frame counter values of respective other communication apparatuses in each key.