Title

Accountable Authority Identity-Based Encryption with Public Traceability

Publication Type

Conference Proceeding Article

Publication Date

3-2013

Abstract

At Crypto’07, Goyal introduced the notion of accountable authority identity-based encryption (A-IBE) in order to mitigate the inherent key escrow problem in identity-based encryption, and proposed two concrete constructions. In an A-IBE system, if the private key generator (PKG) distributes a decryption key or produces an unauthorized decryption box for a user maliciously, it runs the risk of being caught and sued in the court of law with the help of a tracing algorithm. Subsequent efforts focused on constructions of A-IBE schemes with enhanced security. In these A-IBE constructions, the tracing algorithm needs to take a user’s decryption key as input. If the user lost his key or is deliberately uncooperative in court, then we cannot implicate the PKG or the user. An interesting open problem left by Goyal et al. at CCS’08 is to consider the possibility of tracing a decryption box using only a public tracing key, or with the assistance of a tracing authority. In this paper, we address this problem positively. We first extend the original model of A-IBE to accommodate public traceability, and then propose an A-IBE scheme in the new model. To the best of our knowledge, the proposed scheme is the first A-IBE with public traceability.

Discipline

Information Security

Research Areas

Information Security and Trust

Publication

Topics in Cryptology - CT-RSA 2013: The Cryptographers’ Track at the RSA Conference 2013, San Francisco,CA, February 25-March 1: Proceedings

Volume

7779

First Page

324

Last Page

342

ISBN

9783642360954

Identifier

10.1007/978-3-642-36095-4_21

Publisher

Springer Verlag

City or Country

San Francisco, CA

Additional URL

http://dx.doi.org/10.1007/978-3-642-36095-4_21