Paper 2013/440

Revisiting Conditional Rényi Entropies and Generalizing Shannon's Bounds in Information Theoretically Secure Encryption

Mitsugu Iwamoto and Junji Shikata

Abstract

Information theoretic cryptography is discussed based on conditional Rényi entropies. Our discussion focuses not only on cryptography but also on the definitions of conditional Rényi entropies and the related information theoretic inequalities. First, we revisit conditional Rényi entropies, and clarify what kind of properties are required and actually satisfied. Then, we propose security criteria based on Rényi entropies, which suggests us deep relations between (conditional) Rényi entropies and error probabilities by using several guessing strategies. Based on these results, unified proof of impossibility, namely, the lower bounds of key sizes is derived based on conditional Rényi entropies. Our model and lower bounds include the Shannon's perfect secrecy, and the min-entropy based encryption presented by Dodis, and Alimomeni and Safavi-Naini. Finally, a new optimal symmetric key encryption is proposed which achieve our lower bounds.

Metadata
Available format(s)
PDF
Category
Foundations
Publication info
Published elsewhere. Major revision. ICITS2013
Keywords
Information Theoretic Cryptography(Conditional) Rényi entropyImpossibilitySymmetric-key EncryptionSecret Sharing Schemes
Contact author(s)
mitsugu @ uec ac jp
History
2014-09-04: last of 2 revisions
2013-07-18: received
See all versions
Short URL
https://ia.cr/2013/440
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2013/440,
      author = {Mitsugu Iwamoto and Junji Shikata},
      title = {Revisiting Conditional Rényi Entropies and Generalizing Shannon's Bounds in Information Theoretically Secure Encryption},
      howpublished = {Cryptology {ePrint} Archive, Paper 2013/440},
      year = {2013},
      url = {https://eprint.iacr.org/2013/440}
}
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.