In a communication system which can privately inform each applicant of an outcome
of a game or an examination, a cell phone with a cell phone number is used to transmit,
to a center or a promoter, personal identification information including the cell
phone number and a total personal password. The total personal password is obtained
by producing the personal identification information, by producing the result of
the game or examination as a parameter, and by encrypting both the personal identification
information and the result. The center extracts the personal identification information
from the total personal password decrypted and collates the extracted personal
identification information with the received information so as to judge whether
or not a person is authentic. When confirmation is made about the fact that the
person is authentic, the parameter is extracted from the total personal password
to be judged. An outcome of judgement is transmitted to each person by the use
of the cell phone number. The total personal password may be transmitted to the
center through a network.
