TELEPHONE SET FOR ENCIPHERED IC CARD

摘要

PURPOSE:To secure a double high-grade information protecting function for both a key code and an enciphered algorithm by using an IC card as a memory device for dial numbers and enciphering the dial number together with the key code supplied for decoding through the dial digit buttons of the IC card telephone when the dial number is stored in the IC card. CONSTITUTION:An IC 12 card is put into a reading device 15 and a key code is inputted by means of the dial digit buttons 4 of a telephone. A CPU 7 set at the inside of the device 15 collates the input key code with the key code registered on the card 12. Then a command signal is delivered only when coincidence is obtained between both key codes. When an automatic dial transmission button 5 is pushed, the CPU 7 sends a request signal to the card 12 to extract the dial number data corresponding to the pushed button 5 and reads an enciphered dial number out of an EEPROM chip 14 to send it to the CPU 7. This dial number is decoded and restored to the original dial number. Then this original number is sent automatically to a telephone circuit via a telephone main body circuit 9.