Authentication system and the authentication method which use a portable communication terminal

The authentication subsystem used in an authentication system including a mobile Communications Network, a portable communication terminal and the authentication subsystem, said authentication subsystem comprising:

• a password generator that generates said first password information upon receiving an authentication request, said authentication request containing ID information which identifies the owner of said portable communication terminal;
• a database that stores the ID information and a telephone number of said portable phone terminal;
• a converter that converts said first password information to a first password motion picture signal which changes its color at a predetermined frame interval on the basis of said first password information;
• a communication part that searches a telephone number of said portable communication terminal from said database on the basis of said ID information and transmits said first password motion picture signal to a portable communication terminal with the searched telephone number and that receives a second password motion picture signal from said portable communication terminal;
• an inverter that inverts said second password motion picture signal to a second password information;
• and
• a password information comparison part that compares said first and second password information;
• wherein one of said first and second password motion picture signals is transmitted as an optical signal.

An authentication method used in an authentication System which includes a mobile Communications Network, a portable Communication Terminal and an authentication subsystem, comprising the steps of:

• (A) said authentication subsystem, upon receiving an authentication request, generates a first password information, wherein said authentication request contains an ID information specifying the owner of said portable communication terminal;
• (B) said authentication subsystem converts said first password information to a first password motion picture signal which changes its color at a predetermined interval on the basis of said first password information;
• (C) said authentication subsystem searches the telephone number based on said ID information and transmits said first password motion picture signal to the portable communication terminal with the searched telephone number;
• (D) said portable communication terminal receives said first password motion picture signal, transmit it , as said second password motion picture signal, to said authentication subsystem;
• (E) said authentication subsystem inverts said received second password motion picture signal from said portable communication terminal to a second password information;
• and
• (F) said authentication subsystem compares said first and second password information This second password information is compared with the password information;
• wherein one of said first and second password motion picture signals is transmitted as a light signal.