著者

押切 徹 齊藤 泰一

雑誌

情報処理学会論文誌 (ISSN:18827764)

巻号頁・発行日

vol.55, no.9, pp.1964-1970, 2014-09-15

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時限式暗号(Timed-Release Encryption, TRE)とは,復号できる時刻を暗号化の際に指定できる暗号方式である.本稿ではIDベース暗号(Identity-Based Encryption, IBE)にTREの機能を持たせた時限式IDベース暗号(Timed-Release Identity-Based Encryption, TRIBE)を提案し,その安全性定義を行う.さらにIBEとワンタイム署名からなるTRIBEの一般的構成法(generic construction)を示し,定義した安全性を満たすことを証明をする.Timed-Release Encryption (TRE) is an encryption mechanism that allows a receiver to decrypt a ciphertext only after the time that a sender designates. We propose a notion of identity-based encryption scheme with TRE encryption mechanism, timed-release identity-based encryption (TRIBE), and define its security models. Moreover we show a generic construction of TRIBE from IBE and one-time signature, and prove that the constructed scheme achieves the security we defined.