POST-QUANTUM BLIND SIGNATURE PROTOCOL ON NON-COMMUTATIVE ALGEBRAS

A method for constructing a blind signature scheme based on a hidden discrete logarithm problem defined in finite non-commutative associative algebras is proposed. Blind signature protocols are constructed using four-dimensional and six-dimensional algebras defined over a ground finite field GF(p) and containing a global two-sided unit as an algebraic support. The basic properties of the used algebra, which determine the choice of protocol parameters, are described.

An improved E-payment protocol based on quantum blind signature without entanglement

E-payment plays an important role in modern daily life, so the security problem of E-payment has been widely concerned by researchers. In a recent paper [Int. J. Theor. Phys. 57, 2657 (2018)], the authors presented a trusted third-party E-payment protocol based on quantum blind signature without entanglement. In this paper, we show that there is a serious security flaw in their E-payment protocol. That is, the partial keys will be disclosed by performing a simple attack strategy. Furthermore, we propose an improved E-payment protocol and analyze its security.