Cryptology ePrint Archive: Report 2018/590

The Twin Conjugacy Search Problem and Applications

Xiaoming Chen and Weiqing You

Abstract: We propose a new computational problem over the noncommutative group, called the twin conjugacy search problem. This problem is related to the conjugacy search problem and can be used for almost all of the same cryptographic constructions that are based on the conjugacy search problem. However, our new problem is at least as hard as the conjugacy search problem. Moreover, the twin conjugacy search problem has many applications. One of the most important applications, we propose a trapdoor test which can replace the function of the decision oracle. We also show other applications of the problem, including: a non-interactive key exchange protocol and a key exchange protocol, a new encryption scheme which is secure against chosen ciphertext attack, with a very simple and tight security proof and short ciphertexts, under a weak assumption, in the random oracle model.

Category / Keywords: foundations / The twin conjugacy search problem, trapdoor test, CCA, noncommutative group, assumption, crypto

Date: received 7 Jun 2018, last revised 6 Jul 2018

Contact author: 894572560 at qq com

Available format(s): PDF | BibTeX Citation

Version: 20180707:022947 (All versions of this report)

Short URL:

[ Cryptology ePrint archive ]