Paper 2023/441
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.
Metadata
- Available format(s)
- Category
- Secret-key cryptography
- Publication info
- Preprint.
- Keywords
- unconditionally secure cipherentropically-secure symmetric encryptionindistinguishabilityuniversal code
- Contact author(s)
- boris @ ryabko net
- History
- 2023-03-27: approved
- 2023-03-26: received
- See all versions
- Short URL
- https://ia.cr/2023/441
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2023/441, author = {Boris Ryabko}, title = {Unconditionally secure ciphers with a short key for a source with unknown statistics}, howpublished = {Cryptology {ePrint} Archive, Paper 2023/441}, year = {2023}, url = {https://eprint.iacr.org/2023/441} }