关键词: 隐私保护, 安全多方计算, 符号距离, 计算几何, 协议

Abstract: Privacy-preserving signed distance is a special case of secure multi-party computation problem and it can be applied in many fields such as military and commercial fields.Calculating the sign of the signed distance decision space geometric object’s position is an essential method of processing spatial geometric object position.In this paper，one privacy-preserving signed distance protocol is presented to solve the signed distance problem based on scalar product protocol.The security and correctness of the protocol are also discussed.And then the privacy-preserving of the triangle intersection with the plane determines is taken as the example to explain its application.

Key words: privacy-preserving, security multi-party computation, signed distance, computational geometry, protocol