Secure two-party computation of the quadratic function´s extreme minimal value

Privacy-Preserving Computational Geometry (PPCG) is a special Secure Multi-party Computation, which is a hot research in information security. This paper presented a special PPCG problem of secure two-party computing the quadratic function´s extreme minimal value on a secret interval. Based on Paillier´s additive homomorphic and secure comparison protocol, a novel protocol for this problem is proposed. Furthermore, its correctness, security and efficiency are analyzed. The analysis results show that the proposed protocol is much more efficient than current protocol, which can be applied in some military and commercial fields.