A Fixed-Latency Architecture to Secure GOOSE and Sampled Value Messages in Substation Systems

International Electrotechnical Commission (IEC) 62351-6 standard specifies the security mechanisms to protect real-time communications based on IEC 61850. Generic Object Oriented Substation Events (GOOSE) and Sampled Value (SV) messages must be generated, transmitted and processed in less than 3 ms, which challenges the introduction of IEC 62351-6. After evaluating the security threats to IEC 61850 communications and the state of the art in GOOSE and SV security, this work presents a novel architecture based on wire-speed processing able to provide message authentication and confidentiality. This architecture has been implemented and tested to evaluate its performance, resource usage, and the latency introduced. Other proposals in the scientific literature do not support real-time traffic, so they are not suitable for GOOSE and SV messages. Whereas the others exceed the target latency of 3 ms or do not comply with the standards, our design authenticates and encrypts real-time IEC 61850 data in less than 7 mu s-predictable latency-, and complies with IEC 62351:2020.This work was supported in part by the Ministerio de Economia y Competitividad of Spain under Project TEC2017-84011-R, in part by Fondo Europeo de Desarrollo Regional (FEDER) Funds through the Doctorados Industriales program under Grant DI-15-07857, and in part by the Department of Education, Linguistic Policy and Culture of the Basque Government through the Fund for Research Groups of the Basque University System under Grant IT978-16

A Novel Testbed for Evaluation of Operational Technology Communications Protocols and Their On-Device Implementations

Operational Technology (OT) and Infrastructure Technology (IT) systems are converging with the rapid addition of centralized remote management in OT systems. Previously air-gapped systems are now interconnected through the internet with application-specific protocols. This has led to systems that had limited access points being remotely accessible. In different OT sectors, legacy protocols previously transmitted over serial communication were updated to allow internet communication with legacy devices. New protocols such as IEC-61850 were also introduced for monitoring of different OT resources. The IEC-61850 standard’s Generic Object Oriented Substation Event (GOOSE) protocol outlines the representation and communication of a variety of different components through Publisher and Subscriber roles. Each publisher and subscriber are defined specifically on Intelligent Electronic Devices (IEDs), which may differ in manufacturer and capabilities. Each defined publisher and subscriber are network specific, so the different topologies and data types sent can vary between networks. To support the different objects represented in the protocol, customizable configurations for GOOSE supporting components is required. In this thesis, an effective, flexible, and practical testbed is introduced for evaluating OT protocols, with a case study in the implementation of the GOOSE protocol on IEDs. Common cyberattacks on the GOOSE protocol are identified and implemented on the testbed with variable data rate generation. The tests are executed on three separate GOOSE devices, two devices from reputable manufacturers, and a Raspberry Pi running an open source library, libiec61850. Each device is configured in accordance with manufacturer instruction to ensure the test operated under valid operating conditions. Advisor: Hamid R. Sharif-Kashan