Unconditionally secure ciphers with a short key for a source with unknown statistics
Abstract
We consider the problem of constructing an unconditionally secure cipher with a short key for the case where the probability distribution of encrypted messages is unknown. Note that unconditional security means that an adversary with no computational constraints can obtain only a negligible amount of information ("leakage") about an encrypted message (without knowing the key). Here we consider the case of a priori (partially) unknown message source statistics. More specifically, the message source probability distribution belongs to a given family of distributions. We propose an unconditionally secure cipher for this case. As an example, one can consider constructing a single cipher for texts written in any of the languages of the European Union. That is, the message to be encrypted could be written in any of these languages.
Cite
@article{arxiv.2303.15258,
title = {Unconditionally secure ciphers with a short key for a source with unknown statistics},
author = {Boris Ryabko},
journal= {arXiv preprint arXiv:2303.15258},
year = {2023}
}