Communication apparatus, communication system, certificate transmission method, anomaly detection method and a program therefor

摘要

A communication apparatus has a communication part and authenticates a communication partner by using a digital certificate. The communication apparatus includes an authentication part carrying out authentication of the communication partner by using a common certificate. The common certificate is a digital certificate not including identification information of an apparatus. An individualized certificate transmission part acquires, in the case the authentication by the authentication part has been made successfully, an individualized certificate and transmits the individualized certificate to the communication partner. The individualized certificate is a digital certificate including identification information of the communication partner.