| 摘要 |
<p>A modulation/demodulation unit (54), etc., receives a packet signal from a base station device, and receives a packet signal from another terminal device. A processing unit (56) processes the received packet signal. In the modulation/demodulation unit (54), etc., with respect to the packet signal received from the base station device, a secret key of a public key cryptosystem is used for an electronic signature, and a common key of a symmetric-key cryptosystem is used for data; whereas, with respect to the packet signal received from another terminal device, a common key of a symmetric-key cryptosystem is used for an electronic signature.</p> |
