Secure Computing Protocols for Internet of Things Data Fusion Based on Set Intersection and Union Against Malicious Enemies

Data fusion in the Internet of Things (IoT) is based on the intersection and union problems of sets without complete set restrictions to achieve accurate and reliable location services. However, protecting users’ privacy in IoT is challenging, for which a solution is proposed herein in conjunction with secure multiparty computation (MPC). Using the proposed solutions, users’ privacy can be ensured while achieving accurate and reliable location positioning. Current privacy-preserving schemes used for data fusion require a set’s elements belonging to an appropriate complete set, and the range of elements used by such schemes is usually integers. Moreover, a unified range of all elements in a set cannot be determined in real time for practical scenarios. Limiting the range of elements to integers is also impossible, because the type of data collected by IoT devices is uncertain. To address these issues, new encoding and transformation methods are proposed herein to map a set of rational numbers to the Cartesian coordinate system. The NTRU encryption scheme is used to design the intersection and union MPC protocols of rational numbers’ sets without any complete set restriction under the semi-honest model. Then, to prevent possible malicious behaviors in the semi-honest model protocols, MPC protocols for the intersection and union of rational numbers’sets are designed without any complete set. The security of the protocols is demonstrated by applying the real/ideal model paradigm. The comparison of the proposed protocols with other schemes shows that our protocols have higher computational efficiency.