Communication system

A communication system comprising:

• an ID information transmitting terminal device;
• and
• one or more ID information receiving terminal devices,
• wherein the ID information transmitting terminal device and the one or more ID information receiving terminal devices generate the same common key based on a feature element of simultaneously acquirable biological information,
• wherein the ID information transmitting terminal device comprises
• a biological information acquiring unit to acquire the feature element of the biological information;
• a common key generation unit to generate the common key;
• an encryption/decryption unit to encrypt ID information with the common key;
• and
• a communication unit to transmit the encrypted ID information, and
• wherein each of the one or more ID information receiving terminal devices comprises
• a biological information acquiring unit to acquire the feature element of the biological information;
• a common key generation unit to generate the common key;
• a communication unit to receive the encrypted ID information;
• and
• an encryption/decryption unit to decrypt the encrypted ID information with the common key.

A communication system comprising:

• an ID information transmitting terminal device;
• and
• an ID information receiving terminal device,
• wherein the ID information transmitting terminal device and the ID information receiving terminal device generate the same common key based on a simultaneously acquirable feature element,
• wherein the ID information transmitting terminal device comprises
• a feature acquisition unit to acquire the feature element;
• a common key generation unit to generate the common key;
• an encryption/decryption unit to encrypt ID information with the common key;
• and
• a communication unit to transmit the encrypted ID information, and
• wherein the ID information receiving terminal device comprises
• a feature acquisition unit to acquire the feature element;
• a common key generation unit to generate the common key;
• a communication unit to receive the encrypted ID information;
• and
• an encryption/decryption unit to decrypt the encrypted ID information with the common key.