An Experimental Analysis of Power and Delay Signal-to-Noise Requirements for Detecting Trojans and Methods for Achieving the Required Detection Sensitivities

New validation methods are needed for ensuring integrated circuit (IC) Trust, and in particular for detecting hardware Trojans. In this paper, we investigate the signal-to-noise ratio (SNR) requirements for detecting Trojans by conducting ring oscillator (RO) experiments on a set of V2Pro FPGAs. The ROs enable a high degree of control over the switching activity in the FPGAs while simultaneously permitting subtle delay and transient power supply anomalies to be introduced through simple modifications to the RO logic structure. Power and delay analyses are first carried out across a set of FPGAs using RO configurations that emulate Trojan-free conditions. These experiments are designed to determine the magnitude of process and environmental (PE) variations, and are used to establish statistical limits on the noise floor for the subsequent emulated Trojan experiments. The emulated Trojan experiments introduce anomalies in power and delay in subtle ways as additional loads and series inserted gates. The data from both experiments is used to determine the detection sensitivity of several statistical methods to the transient anomalies introduced by these types of design modifications. A calibration technique is proposed that improves sensitivity to small transient anomalies significantly. Finally, we describe testing techniques that enable high resolution measurements of power and delay to support the proposed calibration and statistics-based detection methods.