Patent ID: 8225096

Claim:
A method for authenticating a communication partner using an electronic certificate containing personal information, the method comprising the steps of, in a client apparatus: receiving a request for the electronic certificate from a server apparatus; in response to the reception of the request, reading a client certificate containing personal information and a server public key of the server apparatus from a storage device of the client apparatus; encrypting the client certificate using the server public key; creating a temporary electronic certificate by setting determination information in a first field of an electronic certificate and the encrypted client certificate in a second field of the electronic certificate, of which format is supported by the server apparatus, the determination information indicating that the electronic certificate is a temporary electronic certificate; and sending the temporary electronic certificate to the server apparatus, and the steps of, in the server apparatus: receiving the electronic certificate; retrieving the determination information from the first field of the electronic certificate; determining whether or not the determination information indicates that the electronic certificate is a temporary electronic certificate; if it is determined that the electronic certificate is a temporary electronic certificate, retrieving the encrypted client certificate from the second field of the temporary electronic certificate; decrypting the retrieved client certificate using a server private key corresponding to the server public key; and authenticating the client apparatus using the decrypted client certificate.