国際会議
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Information-Theoretic Timed-Release Security: Key-Agreement, Encryption and Authentication Codes
- 著者
- Y. Watanabe, T. Seito, and J. Shikata
- 会議名
- ICITS 2012
- 巻
- LNCS 7412
- ページ
- 167–186
- 出版社
- Springer
- 発行年
- 2012
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, and we present constructions of those ones. In particular, information-theoretic timed-release encryption and authentication codes can be constructed from information-theoretic timed-release key-agreement in a generic and simple way. Also, we derive tight lower bounds of sizes of secret-keys and show an optimal construction for information-theoretic timed-release key-agreement. 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.