目标成本值最优的物联网WSS蠕虫抑制算法

Optimal Suppression Algorithm Against Worm Propagation in Wireless Service System for IoT Based on Target Cost Function

物联网无线服务系统(wireless service system,WSS)是以通用的协议标准实现人与物、物与物相连的实时网络交互系统.该系统在设备中嵌入无线传感器节点以实现数据上传和决策下发,但传感器节点的同构性特点使得蠕虫传播问题日益严重.为此,在对现有蠕虫传播的流行病模型进行分类并总结各类模型特点的基础上,首先提出了具有睡眠状态和隔离状态的流行病模型,定义了系统中节点的状态转换关系;其次,依据节点的射频通信距离,确定了具有实际传染能力的感染节点数量及范围;再次,引入蠕虫与无线服务系统的目标成本函数,给出了基于目标成本值的完全信息动态微分博弈模型;然后,证明了该博弈存在鞍点策略,利用状态变量、协状态变量和汉密尔顿函数求解鞍点策略并设计了保证目标成本值最优的防御策略算法;最后,仿真实现本算法与2种蠕虫防御策略算法,通过各状态节点的变化特点及目标成本值的对比实验进行性能评估.实验结果表明:基于改进流行病模型的最优防御算法在抑制无线服务系统蠕虫传播方面有明显优势.

With the adoption of the general standard of communication protocol,wireless service system(WSS)in IoT is proposed to achieve the real-time connection between person and things or things and things.According to the characteristics of IEEE 802.15.4,wireless sensor nodes are embedded in the devices for data collection and command broadcasting.However,the isomorphism of the sensor nodes makes the worm propagation an increasingly serious problem.Firstly,based on the classification of epidemiological models related to worm propagation and the analysis of the characteristics of various models,an epidemiological model is constructed,which specially introduces sleep state and quarantine state into state transition.The transition relationship of nodes is defined simultaneously.Secondly,according to the radio frequency,the number and range of infected nodes with actual transmission ability are determined.Thirdly,we introduce the target cost function between worm and wireless service system,and put forward a dynamic differential game with complete information based on the overall damage.Then,the existence of saddle-point solution is proved,which is solved by combining state parameters,cooperative state variables and Hamiltonian functions.The optimal defense algorithm is proposed to minimize target cost function.Finally,different algorithms are implemented and the performance evaluation is carried out by comparing the characteristics of nodes in each state and the corresponding overall damage.The experimental results show that the optimal defense algorithm based on improved epidemic model can suppress worm propagation in wireless service system effectively and efficiently.