Abstract: In order to solve the source reliability problem of Big Data in the Internet of Things, a data reliable assurance model of Internet of Things based on the trust evaluation of perceived source was constructed with the evaluation unit, and each evaluation unit includes three categories, including the work node, the companion node and the decision node. The working nodes which are aware of the same kind of index can be used as the basis for calculating the value of each other’s trust. The companion nodes and decision nodes are used to monitor the status of the working nodes. The companion nodes are used to verify the data of the working nodes regularly, so as to determine the status of the working nodes. The decision node is used when the working node is suspected to be abnormal so as to give the final result. Through the data collection and validation of the above three kinds of nodes, a method for calculating and adjusting the reliability of nodes was presented, which was used to obtain the trust value of each working node. Then, according to the given threshold value, the trust list was constructed, and the non-trusted nodes removed, and only the data perceived by the trusted node gets transmited and processed. At the same time, in order to ensure the initial reliability of the sensor node, the access authentication mechanism is introduced. From the results of theoretical analysis and simulation, the model has the characteristics of reliable node sensing data and flexible expansion, and can effectively improve the reliability of the data source of the Internet of Things.

Key words: Internet of Things, Big Data, trust evaluation , Data reliability, node selection