ENCRYPTION KEY CONFIRMATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To quickly confirm an encryption key distributed from a base station to a terminal in an encryption key confirmation system where the base station can make a simultaneous notice to terminals. SOLUTION: A base station 2 in this encryption key confirmation system designates a number (1) of an auxiliary group of terminals 1a-1c to send a confirmation request signal. The terminals 1a-1c belonging to the auxiliary group (1) encrypts a communication encryption key delivered in a preset timing so as to differentiate a delay time from each terminal and transmits the encrypted key to the base station 2. The base station 2 identifies the terminals 1a-1c according to the time sequence of received information. The base station 2 makes similar arithmetic operation and compares the result with the information sent from the terminals 1a-1c. When not matched, the base station transmits the communication encryption key again because the base station 2 regards that the communication encryption key of the terminal is incorrect. The processing above is repeated and the base station collates and confirms all the auxiliary groups.