Research On Secure Protocols For Determing Geometric Objects Position

Privacy-Preserving computational geometry problem is a newly arisen research realm in the many realms of Secure Multi-Party Computation. The model that it concretely defines:the research of Privacy-Preserving computational geometry problem(briefly name PPCG) is to design protocols, these protocols make participants of mutual cooperation in the process of computing can use other participants privacy informations (such as point,line segment,polygon,flat surface etc.), but can not acquire them value concretely, by the end of computing, in addition to acquiring a calculation result, each participant can not acquire any other informations. Nowadays, the research of this problem in the internation is still at the beginning stage, thus designning efficient and pratical Privacy-Preserving computational geometry protocol have became one of the popular topics that people concentrate on, there is also more extensive application in several realms, such as modern science calculation and military safety.Many scholars have researched the plane geometry problems of Privacy-Preserving computational geometry, the researchs are more deep. Them also have researched the spatial geometry problems of Privacy-Preserving computational geometry what the problems research also obtained good results, but the research of this aspect is less. So this text's range of research mainly highlights in the aspects of the spatial geometry problems of Privacy-Preserving computational geometry, such as spatial geometric objects related position judging problem,spatial vectors computing and related position judging problem etc. this texual main studying as follows:Firstly, according to the secure protocol for the sum of two matrices solve spatial geometric objects related position problem, researching this problem that this text mainly use the concept of matrix Zhi and the secure protocol for the sum of two matrices to design some secure protocols for determining spatial geometric objects related position. Using these protocols to securely judge the problem of the flat surface and the flat surface related position in the space,to securely judge the problem of the flat surface and straight line related position in the space and to securely judge the problem of straight line and straight line related position in the space.Secondly, according to Oblivious Third Party solve spatial geometric objects related position problem. Formerly of research works foundation up led to go into Oblivious Third Party. Researching this problem that this text mainly use the concept of matrix Zhi and Oblivious Third Party to design some secure protocols for determining spatial geometric objects related position. Using these protocols to securely judge the problem of the flat surface and the flat surface related position in the space,to securely judge the problem of the flat surface and straight line related position in the space and to securely judge the problem of straight line and straight line related position in the space, it also lowered the computation price.Thirdly, researching a secret to judge two sets of datas proportional correspondingly problem. Design a safety protocol for computing piece of two sets of datas proportional correspondingly. And use this protocol to further design a safety protocol for determining two sets of datas proportional correspondingly and a safety protocol for determining two spatial flat surfaces related position. This text's research to not only solve a secret to judge two sets of datas proportional correspondingly problem but also to solve two spatial flat surfaces related position determining problem. Compared with the solution in past, this text's solution not only raised the efficiency of the protocol, but also lowered correspondence.At last, researching Privacy-Preserving spatial vectors computing and application problem. Formerly of research works foundation up to further design some secure protocols for computing spatial vectors. And use these protocols to further design a safety protocol for determining spatial four point on the same flat surface and use these protocols to solve some problems for determining spatial vectors related position.