COMMON KEY ENCRYPTION COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide the common key encryption communication system capable of reproducing a plaintext even when jitter exists. SOLUTION: A partial PON clock counter read-out unit 12 reads out a partial PON clock counter (111) that is incremented at a period that is more than two times and less than four times of a maximum jitter amount. A transmitter 1 transmits a least significant bit 111 LSB of a read-out partial PON clock counter with an encryption to a receiver 2. A partial PON clock counter correction unit 24 performs one-time increment or one-time decrement to a partial PON clock counter 211 when a least significant bit 211 LSB is not equal to a least significant bit 111 LSB. A decoding unit 23 performs a decoding with an input block counter IBdec including the partial PON clock counter 211. COPYRIGHT: (C)2007,JPO&INPIT