Research On The Space Between The Different Models Under The Two Parallel Linear Distance Calculation Confidentiality Agreement

Along with the Internet widely used, information resources bring people great interests. Meanwhile, information security stands tough tests. As a benefit of the Internet, multi-party computation becomes possible and privacy protection gains more and more attention. secure multi-party computation becomes a research hotspot and is imported into many application regions, and Privacy-Preserving Computational Geometry is one of them.Secure multi-party computation is introduced first and the research background, status and significance is analyzed. Some basic technology and involved mathematical knowledge about it is also presented.A privacy-preserving computational protocol on the minimum distance between two three-dimension parallel straight line, protocol one, is proposed based on semi-honest model. The correctness and security is proved in detail. Upon this one, an extended protocol applied to malicious model, protocol two, is given. Protocol two expands the first one suitable to malicious condition, which means, if there is a malicious participate, during the process, it could not obtain any other’s privacy information but those it should get. Protocol two is secure after a single execution. But there is possibility that after multiple computations, malicious participant may gain others’straight line information. Therefore protocol three, an improved sharing distance protocol between two three-dimension parallel straight line based on malicious model is proposed. Secret sharing guarantees that both participants could share their distance securely.An analysis about above mentioned protocols is given at chapter five. The three ones hide privacy information using the same method. However, different participants result in different methods to ensure security. Three protocols’suitable objects and interruption situations are given, so does the information exchanging round number and security.