Publications

This document describes a microgrid cyber security reference architecture leveraging defense- in-depth techniques that are executed by first describing actor communication using data exchange attributes, then segmenting the microgrid control system network into enclaves, and finally grouping enclaves into functional domains. To illustrate the design approach, two notional microgrid control implementations are presented. Both include a discussion on types of communication occurring on that network, data exchange attributes for the actors, and examples of segmentation via enclaves and functional domains. The second example includes results from Red Team analysis and quantitative scoring according to a novel system that derives naturally from the implementation of the cyber security architecture. Acknowledgements Sandia National Laboratories and the SPIDERS technical team would like to acknowledge the following for help in the project: * Mike Hightower, who has been the key driving force for Energy Surety Microgrids * Juan Torres and Abbas Akhil, who developed the concept of microgrids for military installations * Merrill Smith, U.S. Department of Energy SPIDERS Program Manager * Ross Roley and Rich Trundy from U.S. Pacific Command * Bill Waugaman and Bill Beary from U.S. Northern Command * Tarek Abdallah, Melanie Johnson, and Harold Sanborn of the U.S. Army Corps of Engineers Construction Engineering Research Laboratory * Colleagues from Sandia National Laboratories (SNL), Oak Ridge National Laboratory (ORNL), Idaho National Laboratory (INL), Massachusetts Institute of Technology Lincoln Laboratory (MIT-LL), United States Pacific Command (USPACOM), and the Joint Information Operations Warfare Center (JIOWC) for their reviews, suggestions, and participation in the work.

This document describes a microgrid cyber security reference architecture. First, we present a high-level concept of operations for a microgrid, including operational modes, necessary power actors, and the communication protocols typically employed. We then describe our motivation for designing a secure microgrid; in particular, we provide general network and industrial control system (ICS)-speci c vulnerabilities, a threat model, information assurance compliance concerns, and design criteria for a microgrid control system network. Our design approach addresses these concerns by segmenting the microgrid control system network into enclaves, grouping enclaves into functional domains, and describing actor communication using data exchange attributes. We describe cyber actors that can help mitigate potential vulnerabilities, in addition to performance bene ts and vulnerability mitigation that may be realized using this reference architecture. To illustrate our design approach, we present a notional a microgrid control system network implementation, including types of communica- tion occurring on that network, example data exchange attributes for actors in the network, an example of how the network can be segmented to create enclaves and functional domains, and how cyber actors can be used to enforce network segmentation and provide the neces- sary level of security. Finally, we describe areas of focus for the further development of the reference architecture.

Threats are generally much easier to list than to describe, and much easier to describe than to measure. As a result, many organizations list threats. Fewer describe them in useful terms, and still fewer measure them in meaningful ways. This is particularly true in the dynamic and nebulous domain of cyber threats - a domain that tends to resist easy measurement and, in some cases, appears to defy any measurement. We believe the problem is tractable. In this report we describe threat metrics and models for characterizing threats consistently and unambiguously. The purpose of this report is to support the Operational Threat Assessment (OTA) phase of risk and vulnerability assessment. To this end, we focus on the task of characterizing cyber threats using consistent threat metrics and models. In particular, we address threat metrics and models for describing malicious cyber threats to US FCEB agencies and systems.

The key piece of knowledge necessary for building defenses capable of withstanding or surviving cyber and kinetic attacks is an understanding of the capabilities posed by threats to a government, function, or system. With the number of threats continuing to increase, it is no longer feasible to enumerate the capabilities of all known threats and then build defenses based on those threats that are considered, at the time, to be the most relevant. Exacerbating the problem for critical infrastructure entities is the fact that the majority of detailed threat information for higher-level threats is held in classified status and is not available for general use, such as the design of defenses and the development of mitigation strategies. To reduce the complexity of analyzing threat, the threat space must first be reduced. This is achieved by taking the continuous nature of the threat space and creating an abstraction that allows the entire space to be grouped, based on measurable attributes, into a small number of distinctly different levels. The work documented in this report is an effort to create such an abstraction.