Security Analysis of One-time System and Its Betterment

As Shannon had proved that one-time system is perfect secrecy,one-time system is deemed to be un- breakable.The paper analyzes the implied presupposition and mistake in Shannon's attestation.it is pointed out that Bayes' theorem was used mistakenly in his proof because of his mixing up the probabilities under different con- ditions.At the same time betterment of one-time system is provided.