论文标题
与间歇性数据身份验证的攻击弹性状态估计
Attack-Resilient State Estimation with Intermittent Data Authentication
论文作者
论文摘要
基于网络的对控制系统的攻击可能会改变传递给控制器的传感器数据，从而有效地导致控制性能下降。结果，即使在对传感器测量攻击的情况下，也可以访问准确的状态估计值，这也是至关重要的。在本文中，我们分析了弹性攻击者可能会损害任何传感器时的弹性状态估计器（RSE）的性能。具体而言，我们考虑使用众所周知的基于L0的RSE和两个常用的声音入侵检测器（IDS）的系统。对于有界噪声的线性时间不变的植物，当攻击可能导致无限估计错误时，我们定义了完美攻击性（PA）的概念，而在未经使用的ID（即隐形）的情况下仍未发现。我们得出必要且充分的PA条件，表明即使植物稳定，系统也可以完全攻击。虽然可以使用标准加密机制（例如，消息身份验证）来防止PA，以确保基于网络的攻击下的数据完整性，但它们的连续使用会引起大量的通信和计算开销。因此，我们还研究了在存在隐秘攻击的情况下，即使是间歇性使用数据身份验证对RSE绩效保证的影响。我们表明，如果来自某些传感器的消息甚至是间歇性身份验证的，那么隐秘的攻击就无法导致无限状态估计错误。
Network-based attacks on control systems may alter sensor data delivered to the controller, effectively causing degradation in control performance. As a result, having access to accurate state estimates, even in the presence of attacks on sensor measurements, is of critical importance. In this paper, we analyze performance of resilient state estimators (RSEs) when any subset of sensors may be compromised by a stealthy attacker. Specifically, we consider systems with the well-known l0-based RSE and two commonly used sound intrusion detectors (IDs). For linear time-invariant plants with bounded noise, we define the notion of perfect attackability (PA) when attacks may result in unbounded estimation errors while remaining undetected by the employed ID (i.e., stealthy). We derive necessary and sufficient PA conditions, showing that a system can be perfectly attackable even if the plant is stable. While PA can be prevented with the use the standard cryptographic mechanisms (e.g.,message authentication) that ensure data integrity under network-based attacks, their continuous use imposes significant communication and computational overhead. Consequently, we also study the impact that even intermittent use of data authentication has on RSE performance guarantees in the presence of stealthy attacks. We show that if messages from some of the sensors are even intermittently authenticated, stealthy attacks could not result in unbounded state estimation errors.
