Information-Theoretic Timed-Release Security: Key-Agreement, Encryption, and Authentication Codes

Yohei Watanabe; Takenobu Seito; Junji Shikata

Paper 2012/460

Information-Theoretic Timed-Release Security: Key-Agreement, Encryption, and Authentication Codes

Yohei Watanabe, Takenobu Seito, and Junji Shikata

Abstract

In this paper, we study timed-release cryptography with information-theoretic security. As fundamental cryptographic primitives with information-theoretic security, we can consider key-agreement, encryption, and authentication codes. Therefore, in this paper we deal with information-theoretic timed-release security for all those primitives. Specifically, we propose models and formalizations of security for information-theoretic timed-release key-agreement, encryption, and authentication codes; we also derive tight lower bounds on entities' memory-sizes required for all those ones; and we show optimal constructions of all those ones. Furthermore, we investigate a relationship of mechanisms between information-theoretic timed-release key-agreement and information-theoretic key-insulated key-agreement. It turns out that there exists a simple algorithm which converts the former into the latter, and vice versa. In the sense, we conclude that these two mechanisms are essentially close.

Note: We improved the proof of Theorem 5.

Metadata

Available format(s): PDF
Category: Cryptographic protocols
Publication info: Published elsewhere. Major revision. ICITS2012
DOI: 10.1007/978-3-642-32284-6_10
Keywords: timed-release security information-theoretic security unconditional security
Contact author(s): watanabe-yohei-xs @ ynu jp
History: 2015-07-29: last of 5 revisions; 2012-08-13: received; See all versions
Short URL: https://ia.cr/2012/460
License: CC BY

BibTeX

@misc{cryptoeprint:2012/460,
      author = {Yohei Watanabe and Takenobu Seito and Junji Shikata},
      title = {Information-Theoretic Timed-Release Security: Key-Agreement, Encryption, and Authentication Codes},
      howpublished = {Cryptology {ePrint} Archive, Paper 2012/460},
      year = {2012},
      doi = {10.1007/978-3-642-32284-6_10},
      url = {https://eprint.iacr.org/2012/460}
}