A Game-theoretic Framework for Security-aware Sensor Placement Problem in Networked Control Systems
A Game-theoretic Framework for Security-aware Sensor Placement Problem in Networked Control Systems
复制标题
网络控制系统中安全感知传感器放置问题的博弈论框架
DOI：
10.23919/acc.2019.8814443
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
K. Johansson
中科院分区：
文献类型：
--
作者：
Mohammad Pirani;Ehsan Nekouei;H. Sandberg;K. Johansson
为了提高网络控制系统的安全性，研究了网络控制系统中的传感器布置问题。该问题被制定为攻击者和检测器之间的零和博弈。攻击者的决定是选择网络的$f$个节点进行攻击，而检测器的决定是放置$f$个传感器来检测攻击信号的存在。在我们的公式中，攻击者最小化其可见性，定义为从攻击信号到部署的传感器输出的系统L2增益，检测器最大化攻击信号的可见性。博弈的均衡策略决定了传感器的最优位置。研究了当底层连通图是有向树和无向树时，攻击者-检测者博弈纳什均衡的存在性。当游戏不承认一个纳什均衡，它表明，Stackelberg均衡的游戏，检测器作为游戏的领导者，可以有效地计算。研究结果表明，在最优传感器配置策略下，无向拓扑结构比相应的有向拓扑结构能为网络控制系统提供更高的安全性。
This paper studies the sensor placement problem in a networked control system for improving its security against cyber-physical attacks. The problem is formulated as a zero-sum game between an attacker and a detector. The attacker's decision is to select $f$ nodes of the network to attack whereas the detector's decision is to place $f$ sensors to detect the presence of the attack signals. In our formulation, the attacker minimizes its visibility, defined as the system L2 gain from the attack signals to the deployed sensors' outputs, and the detector maximizes the visibility of the attack signals. The equilibrium strategy of the game determines the optimal locations of the sensors. The existence of Nash equilibrium for the attacker-detector game is studied when the underlying connectivity graph is a directed or an undirected tree. When the game does not admit a Nash equilibrium, it is shown that the Stackelberg equilibrium of the game, with the detector as the game leader, can be computed efficiently. Our results show that, under the optimal sensor placement strategy, an undirected topology provides a higher security level for a networked control system compared with its corresponding directed topology.