A Noninvasive Threat Analyzer for Advanced Metering Infrastructure in Smart Grid

Advanced Metering Infrastructure (AMI) is the core component in a smart grid that exhibits a highly complex network configuration. AMI comprises heterogeneous cyber-physical components, which are interconnected through different communication media, protocols, and security measures. They are operated using different data delivery modes and security policies. The inherent complexity and heterogeneity in AMI significantly increases the potential of security threats due to misconfiguration or absence of defense, which may cause devastating damage to AMI. Therefore, there is a need for creating a formal model that can represent the global behavior of AMI configuration in order to verify the potential threats. In this paper, we present SmartAnalyzer, a security analysis tool, which offers manifold contributions: (i) formal modeling of AMI configuration that includes device configurations, topology, communication properties, interactions among the devices, data flows, and security properties; (ii) formal modeling of AMI invariants and user-driven constraints based on the interdependencies among AMI device configurations, security properties, and security control guidelines; (iii) verifying the AMI configuration's compliance with security constraints using a Satisfiability Modulo Theory (SMT) solver; (iv) reporting of potential security threats based on constraint violations, (v) analyzing the impact of potential threats on the system; and (vi) systematic diagnosing of SMT unsatisfiable traces and providing necessary remediation plans. The accuracy and scalability of the tool are evaluated on an AMI testbed and various synthetic test networks.