Abstract

The only known method to exchange secret information through a communication channel in a proven secure way, is to use the so-called one-time pad. in this technique, the data, which is represented by a string of bits, is combined with a random string of bits of equal length called the key, and is then sent through the communication channel. The randomness of the key ensures that the encoded message is also completely random and as such totally unintelligible to a potential eavesdropper. The safety of the transmission is thus entirely dependent on the safety of the key, which has to be secret and shared just by both legitimate users. Moreover, safety can be guaranteed only if the key is used once, and then discarded.

© 1995 IEEE