An efficient fully dynamic group signature with message dependent opening from lattice

Abstract

Abstract Message-dependent opening is one of the solutions to solve the problem of the tracing manager owns excessive power. In this paper, we present a new lattice-based fully dynamic group signature scheme with message-dependent opening by combining an improved version of the fully dynamic group signature scheme proposed by Ling et al and the double encryption paradigm. In addition, we propose an improved underlying zero knowledge protocol, it has a soundness error 1 max ( n , p ) + 1 $\frac {1}{\max (n,p)+1}$ that is better than the Stern-like protocol, which helps to bring down the communication complexity of the protocol and hence the signature scheme. Our scheme constrains the power of group managers by adding an admitter, and the signature size has a logarithmic relationship with the group size.

Keywords

• Dynamic group signature
• Message-dependent opening
• NIZK
• LWE
• SIS