Circuit Techniques for Low-Power and Secure Internet-of-Things Systems

Abstract:

The Internet of Things (IoT) is expected to connect our physical world with billions of sensors and actuators, transforming the way we live and work, as well as creating enormous business markets. Security and privacy are one of the most critical challenges to IoT growth in the future. Because of the severe energy and cost constraints as well as physical exposure of the IoT devices to attackers, software-only security cannot meet the performance demands and faces a variety of new threats targeting hardware. This dissertation proposes several hardware designs for low-power and secure IoT systems.

First, this work presents robust and portable true random number generators (TRNG) and physically unclonable functions (PUF) as roots of trusts for key generation and storage. Several of the designs employ commonly avoided higher order harmonics in multi-mode oscillators as entropy sources. Secondly, finding potential security flaws is an
Indispensable part of enhancing system security. This work unveils one potential vulnerability of integrated circuits by presenting a hardware Trojan attack leveraging analog behaviors of digital processors, which represents the first fabrication-time hardware attack that is small, stealthy, and controllable. Lastly, a digital temperature sensor for IoT is proposed, which achieves state-of- the-art sensing performance with minimized energy and area costs.