| 摘要 |
Known methods for, by way of enciphering/deciphering messages, providing access to information, per authorised user transmit an enciphered message which, since only an authorised user disposes of a deciphering method, may be deciphered by him only. By transmitting the same message to all users, which message has been enciphered per user by way of an enciphering method associated with said user if said user has not been authorised, and has not been enciphered if said user has been authorised, with a user not disposing of the deciphering method associated with him and disposing of the deciphering methods associated with other users, all users receive this same message, while only the authorised users may decipher the enciphered message and may gain access to the information by way of the message deciphered by them, and the unauthorised users cannot gain access to the information by way of the message still enciphered for them, and the method is given an efficient nature. <IMAGE> |
