Shannon has proved fifty years ago that in order to ensure information theoretic secrecy in encryption, the sender and receiver must share a secret key with entropy greater than the entropy of the message to be encrypted. Maurer has suggested in 1990 the bounded storage model for encryption as a way to overcome the Shannon barrier. We shall present a practical encryption scheme based on the bounded storage model, and prove that it is information theoretically secure against the strongest attacks by an adversary with unlimited computing power.

The talk will survey fundamental cryptographic concepts and will be self-contained.