COMMUNICATION APPARATUS, SERVER APPARATUS AND COMMUNICATION PROGRAM

摘要

A communication apparatus comprises: a data receiving unit (514) that receives first signature subject information, which includes both first apparatus identifying information for identifying another communication apparatus and a "piece", and that also receives a first electronic signature generated for the first signature subject information; a unique information storing unit (510) that stores second apparatus identifying information for identifying the communication apparatus and that also stores a non-public key assigned to the communication apparatus; an electronic signature generating unit (521) that uses the non-public key to generate a second electronic signature for second signature subject information including the first signature subject information, first electronic signature and second apparatus identifying information; and a data transmitting unit (515) that transmits the second signature subject information and second electronic signature.