A Survey on Silicon PUFs

Integrated Circuits (ICs) and electronic devices have become an integral part of daily human life (mobile, home, car, etc.). However, specific security measures should be taken to protect the communicated information to and from these devices. However, the existing conventional security primitives require large amounts of memory capacity, processing power, and energy resources that contradict the specific nature of devices. On the other hand, they store secret keys on the devices for future use, making them vulnerable to physical attacks. A new concept, known as Physically Unclonable Functions (PUFs), has been recently investigated to mitigate this problem. A PUF is a hardware-specific security primitive uses the randomness found in the disorder of physical media caused by the manufacturing variation process to provide cryptographic functionalities. Consequently, PUFs are inexpensive to fabricate, prohibitively challenging to duplicate, admit no compact mathematical representation, and are intrinsically tamper-resistant. This manuscript gives a complete survey of PUFs as a promising research field in security with a wide application, especially with connected devices. First, we motivate our contribution by comparing it with the existing surveys about PUFs. Then we provide the needed background to understand PUF architectures and applications by covering: the variability and randomness concepts, their classes, and properties. Then, we survey the existing initiatives related to silicon PUFs in terms of implementation and design used to extract unique secret information from the physical characteristics of an integrated circuit. In addition, we compare the surveyed works in terms of performance and security. Furthermore, we classify and compare the existing silicon PUF applications and use cases. Before concluding, we give the principal metrics used to evaluate the PUFs’ performance and present some related attacks. Finally, we talk about the current limitations of silicon PUF architectures and applications, and we look at and talk about research opportunities and major trends.