Title
Dynamic Threshold Public-Key Encryption With Decryption Consistency From Static Assumptions
Abstract
Dynamic threshold public-key encryption (dynamic TPKE) is a natural extension of ordinary TPKE which allows decryption servers to join the system dynamically after the system is set up, and allows the sender to dynamically choose the authorized set and the decryption threshold at the time of encryption. Currently, the only known dynamic TPKE scheme is a scheme proposed by Delerabl'ee and Pointcheval (CRYPTO 2008). This scheme is proven to provide message confidentiality under a q-type assumption, but to achieve decryption consistency, a random oracle extension is required.In this paper we show conceptually simple methods for constructing dynamic TPKE schemes with decryption consistency from only static assumptions (e.g., the decisional linear assumption in bilinear groups) without relying on random oracles. Our first construction is a purely generic construction from public-key encryption with non-interactive opening (PKENO) formalized by Damgard et al. (CT-RSA 2008). However, this construction achieves a slightly weaker notion of decryption consistency compared to the random oracle extension of the Delerablee and Pointcheval scheme, which satisfies the notion defined by Boneh, Boyen and Halevi (CT-RSA 2005). Our second construction uses a specific PKENO scheme based on the decisional linear assumption in combination with the efficient zero-knowledge proofs by Groth and Sahai. In contrast to our first construction, our second construction achieves the stronger notion of decryption consistency defined by Boneh, Boyen and Halevi.
Year
DOI
Venue
2015
10.1007/978-3-319-19962-7_5
INFORMATION SECURITY AND PRIVACY (ACISP 2015)
Field
DocType
Volume
Confidentiality,Computer security,Computer science,Server,Communication source,Random oracle,Commitment scheme,Theoretical computer science,Encryption,Probabilistic encryption,Public-key cryptography
Conference
9144
ISSN
Citations 
PageRank 
0302-9743
2
0.38
References 
Authors
20
5
Name
Order
Citations
PageRank
Yusuke Sakai1198.19
Keita Emura231636.97
Jacob C. N. Schuldt338522.91
Goichiro Hanaoka4910101.53
Kazuo Ohta559763.83