| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform safe data communication by prolonging the service life of an encryption key. <P>SOLUTION: A common key encryption communication system comprises a station side device and a subscriber side device. In the system, the station side device to be connected to IP network and the subscriber side device are connected through an optical transmission medium on a PON system, and data transmission/reception is performed by a data frame on the optical transmission medium by using an encryption key. The system includes an encryption unit for encrypting plaintext data by using a combination of a cycle counter and a clock counter, and further includes a decryption unit for decrypting encryption data by using the combination of a cycle counter and a clock counter. <P>COPYRIGHT: (C)2013,JPO&INPIT |
