Wang et al. recently proposed an improved edition based on Tseng-Jan group signature scheme[1]. In the paper, we show that the scheme is untraceable by a simple attack.

Lattice-based cryptography is a field of research that has been very active in the last decade. It offers expressiveness along with asymptotic efficiency and seems to the best of our knowledge to be resistant to quantum computers attacks. Advanced cryptography would then benefit from being designed from lattice assumptions. Along those primitives, there is one that grabs our interest: group sig...

We define an unstable equivariant motivic homotopy category for an algebraic group over a Noetherian base scheme. We show that equivariant algebraic K-theory is representable in the resulting homotopy category. Additionally, we establish homotopical purity and blow-up theorems for finite abelian groups.

MANET security has long been an issue for its infrastructure-less nature. The sort of networks gives rise to authentication and key-management problems in MANETs. The absolute TTP based schemes seem to be infeasible for being adopted in MANETs and so are the non-TTP based self-organized schemes which suffer security problems regarding key identity of nodes. A hybrid scheme can serve the purpose...

Group signatures, introduced by Chaum and van Heijst, allow members of a group to sign messages anonymously on behalf of the group. Only a designated group manager is able to identify the group member who issued a given signature. Many applications of group signatures, for example, electronic market, require that the group manager can be split into a membership manager and a revocation manager....