Design of error-free perfect secrecy system by prefix codes and partition codes

We investigate how to design an error-free and perfectly secure crypto-system. In particular, we are interested in the efficiency of an EPS system. A approach based on prefix codes is introduced. Also an optimum partition code is introduced where the key consumption is minimum for fixed number of channel uses. Results obtained in this paper can also be applied to study the tradeoff between the key consumption and the number of channel uses needed to transmit the encrypted message.