Holistic Framework for Evaluating the Trustworthiness of Integrated Circuits

New applications such as autonomous driving, cyber-physical systems, or remote surgeries demand integrated circuits (ICs) with an ever-lower tolerance for failure. Typical IC design focuses on the targets of functionality and power, performance, and area. An emerging topic in IC design is trustworthiness. It attempts to unify the various interdependent functional and non-functional aspects, such as correct functionality, reliability, security, and functional safety. Existing methodologies and standards focus on evaluating trustworthiness issues (TIs), i.e., causes of faults, and their effects on only one particular attribute. Instead, TIs should be evaluated on their effect on trustworthiness as a whole, which demands a holistic approach. In this paper, we make two main contributions. The first contribution is a framework with a set of unified evaluation criteria that can be applied across all trustworthiness attributes, and a metric, called the Residual Risk Value (RRV). The latter can be used to assess the residual risk of a TI, where a low RRV indicates low risk remaining, and vice versa. RRV considers the impact and likelihood, and the potential for risk reduction enabled by implementing countermeasures. The second contribution is a questionnaire-based measure that ranks TIs according to the priority of addressing them. The results highlight that TIs that emerge during the early stages of IC development should be treated with greater priority. Further, there is a tendency to prioritize security-related TIs as a greater risk to trustworthy ICs. Meanwhile, TIs affecting well-established aspects of IC design and verification are given a lower priority.