Wireless sensor network is a key technology in Internet of Things. However, due to the large number of sensor nodes and limited security capability, aging nodes and malicious nodes increase. In order to detect the untrusted nodes in the network quickly and effectively and ensure the reliable operation of the network, this paper proposes a dynamic network security mechanism. Firstly, the direct trust value of the node is established based on its behavior in the regional information interaction. Then, the comprehensive trust value is calculated according to the trust recommendation value and energy evaluation value of other high-trust nodes. Finally, node reliability and management nodes are updated periodically. Malicious nodes are detected and isolated according to the credibility to ensure the dynamic, safe, and reliable operation of the network. Simulation results and analysis show that the node trust value calculated by this mechanism can reflect its credibility truly and accurately. In terms of reliable network operation, the mechanism can effectively detect malicious nodes, with higher detection rate, avoid the risk of malicious nodes as management nodes, reduce the energy consumption of nodes, and also play a defensive role in DOS attacks in wireless sensor networks.

中文翻译：

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无线传感器网络中基于信任管理的动态网络安全机制

无线传感器网络是物联网的关键技术。但是，由于大量的传感器节点和有限的安全性，老化的节点和恶意节点会增加。为了快速有效地检测网络中的不信任节点，确保网络的可靠运行，提出了一种动态的网络安全机制。首先，基于节点在区域信息交互中的行为，建立节点的直接信任值。然后，根据其他高信任度节点的信任度推荐值和能量评估值，计算出综合信任度值。最后，节点可靠性和管理节点会定期更新。根据信誉检测并隔离恶意节点，以确保网络的动态，安全和可靠运行。仿真结果和分析表明，该机制计算出的节点信任度可以真实，准确地反映其可信度。在可靠的网络运行方面，该机制可以有效地检测恶意节点，具有较高的检测率，避免了恶意节点作为管理节点的风险，降低了节点的能耗，并且在无线传感器网络的DOS攻击中起到了防御作用。