METHOD FOR ENCRYPTING AND DECRYPTING MESSAGE, IN WHICH MEK IS ALWAYS VARIED

摘要

PURPOSE: A method for encrypting and decrypting a message is provided to enhance the security in a secure communication process by encrypting and decrypting application data in bit stream units of various lengths. CONSTITUTION: A transmission part for transmitting a message and a reception part for receiving the message share a PSK(Pre-Shared Key)(S10). The transmission part generates a random PSK by using the sharing PSK and a present transmission message number(S11). The present transmission message is encrypted by utilizing an encryption function using the random PSK as an input parameter(S12). The reception part decrypts the encrypted message(S14-S16).