In wireless sensor network (WSNs), the reliability and fault tolerance are the important metrics to evaluate the stability of WSNs. In actual use of WSNs, there often happen many faults and interferences, so we can use the Fault Injection (FI) technology to inject these faults and interferences into WSNs artificially. Through the observation of network reaction we can evaluate the reliability and fault tolerance of the network, so as to make the changes of the network mechanism in order to improve reliability and stability. In this paper we put forward a new performance evaluation system for WSN reliability evaluation with FI, and its inject method based on software, and connect the WSN nodes through a special port in a onetoone manner, so we can inject the fault command to the WSN nodes. First, the FISDR can effectively inject the various practical faults and interferences which WSNs likely encounter, and we can observe the network reaction; Second, the FISDR can receive including WSN nodes and other various equipment through special ports and store them; Finally, the FISDR is equipped with the PC software to monitor the network topology structure, record the transmission rate and analyze the enormou amount of information stored in devices, so that we can test WSNs and evaluate the reliability. We test this system in a fivestorey office and we use dozens of WSN nodes and FISDR nodes separately. Our experiments mainly include such contents. We use FISDR to inject the mass number of faults to WSNs and record the network reaction, so we can verify the effect of FISDR fault injection, so as to test and analyze the FISDR performance. The experimental results show that FISDR can inject various kinds of faults to WSNs effectively and evaluate the WSNs reliability effectively, and it has high an application value in WSN testing and reliability evaluation.
