%0 Book Section
%B Advances in Cryptology – ASIACRYPT 2009
%D 2009
%T Improved Non-committing Encryption with Applications to Adaptively Secure Protocols
%A Choi, Seung Geol
%A Dana Dachman-Soled
%A Malkin, Tal
%A Wee, Hoeteck
%E Matsui, Mitsuru
%K adaptive corruption
%K Algorithm Analysis and Problem Complexity
%K Applications of Mathematics
%K Data Encryption
%K Data Structures, Cryptology and Information Theory
%K Discrete Mathematics in Computer Science
%K non-committing encryption
%K public-key encryption
%K secure multi-party computation
%K Systems and Data Security
%X We present a new construction of non-committing encryption schemes. Unlike the previous constructions of Canetti et al. (STOC ’96) and of Damgård and Nielsen (Crypto ’00), our construction achieves all of the following properties: Optimal round complexity. Our encryption scheme is a 2-round protocol, matching the round complexity of Canetti et al. and improving upon that in Damgård and Nielsen. Weaker assumptions. Our construction is based on trapdoor simulatable cryptosystems, a new primitive that we introduce as a relaxation of those used in previous works. We also show how to realize this primitive based on hardness of factoring. Improved efficiency. The amortized complexity of encrypting a single bit is O(1) public key operations on a constant-sized plaintext in the underlying cryptosystem. As a result, we obtain the first non-committing public-key encryption schemes under hardness of factoring and worst-case lattice assumptions; previously, such schemes were only known under the CDH and RSA assumptions. Combined with existing work on secure multi-party computation, we obtain protocols for multi-party computation secure against a malicious adversary that may adaptively corrupt an arbitrary number of parties under weaker assumptions than were previously known. Specifically, we obtain the first adaptively secure multi-party protocols based on hardness of factoring in both the stand-alone setting and the UC setting with a common reference string.
%B Advances in Cryptology – ASIACRYPT 2009
%S Lecture Notes in Computer Science
%I Springer Berlin Heidelberg
%P 287 - 302
%8 2009/01/01/
%@ 978-3-642-10365-0, 978-3-642-10366-7
%G eng
%U http://link.springer.com/chapter/10.1007/978-3-642-10366-7_17