An Encryption Technique for Provably Secure Transmission from a High Performance Computing Entity to a Tiny One

An encryption/decryption approach is proposed dedicated to one-way communication between a transmitter which is a computationally powerful party and a receiver with limited computational capabilities. The proposed encryption technique combines traditional stream ciphering and simulation of a binary channel which degrades channel input by inserting random bits. A statistical model of the proposed encryption is analyzed from the information-theoretic point of view. In the addressed model an attacker faces the problem implied by observing the messages through a channel with random bits insertion. The paper points out a number of security related implications of the considered channel. These implications have been addressed by estimation of the mutual information between the channel input and output and estimation of the number of candidate channel inputs for a given channel output. It is shown that deliberate and secret key controlled insertion of random bits into the basic ciphertext provides security enhancement of the resulting encryption scheme.