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We present a unique virtual testbed that combines a data-plane programmable network emulator and a power distribution system simulator to evaluate smart grid security and resilience applications. The testbed employs a virtual time system for effective simulation synchronization and fidelity enhancement. We showcase the advantages of the simulation testbed through an anomaly detection case study. 

P4’s data-plane programmability allows for highly customizable and programmable packet processing, enabling rapid innovation in network applications, such as virtualization, security, load balancing, and traffic engineering. Researchers extensively use Mininet, a popular network emulator, integrated with BMv2, for fast and flexible prototyping of these P4-based applications, but due to its lower performance in terms of throughput and latency compared to a production-grade software switch like Open vSwitch, it is crucial to have an accurate and scalable emulation testbed. In this paper, we develop a lightweight virtual time system and integrate it into Mininet with BMv2 to enhance fidelity and scalability. By scaling the time of interactions between containers and the underlying physical machine by a time dilation factor (TDF), we can trade time with system resources, making the emulated P4 network appear to be faster from the viewpoint of the switch/host processes in the container. Our experimental results show that the testbed can accurately emulate much larger networks with high loads, scaled by a factor of TDF with extremely low system overhead. 

Given the scale and mission-critical nature of production networks today, it is essential to solidify their resilience to link failures. Building this resilience in each application separately is not scalable. In order to minimize downtime, at least some degree of resilience should be built directly into the data plane. Fast Failover groups in OpenFlow offer a mechanism to achieve this, but programming them introduces additional complexity to the existing arduous task of developing an SDN controller application. In this paper, we discuss how this complexity can be decoupled from the controller implementation. We introduce FORTIFY, a transparent resiliency layer that incorporates data plane fault tolerance into any existing controller application without any modification to it. FORTIFY operates as a shim layer between the controller and the data plane, and dynamically transforms the data plane rules computed by the controller to use Fast Failover groups. FORTIFY can be used off-The-shelf, or customized programmatically to choose specific types of backup paths. Experimental results collected on a production testbed demonstrate that FORTIFY is a practical, high-performance solution to data plane fault tolerance in SDNs. 

Phasor Measurement Units (PMU), due to their capability for providing highly precise and time-synchronized measurements of synchrophasors, have now become indispensable in wide area monitoring of power-grid systems. Successful and reliable delivery of synchrophasor packets from the PMUs to the Phasor Data Concentrators (PDCs) and beyond, requires a backbone communication network that is robust and resilient to failures. These networks are vulnerable to a range of failures that include cyber-attacks, system or device level outages and link failures. In this paper, we present a framework to evaluate the resilience of a PMU network in the context of link failures. We model the PMU network as a connected graph and link failures as edges being removed from the graph. Our approach, inspired by model checking methods, involves exhaustively checking the reachability of PMU nodes to PDC nodes, for all possible combinations of link failures, given an expected number of links fail simultaneously. Using the IEEE 14-bus system, we illustrate the construction of the graph model and the solution design. Finally, a comparative evaluation on how adding redundant links to the network improves the Power System Observability, is performed on the IEEE 118 bus-system.