Physical unclonable function

A physical unclonable function (sometimes also called physically-unclonable function, which refers to a weaker security metric than a physical unclonable function), or PUF, is a physical object which operation cannot be reproduced ("cloned") in physical way (by making another system using the same technology), that for a given input and conditions (challenge), provides a physically defined "digital fingerprint" output (response). that serves as a unique identifier, most often for a semiconductor device such as a microprocessor. PUFs are often based on unique physical variations occurring naturally during semiconductor manufacturing. A PUF is a physical entity embodied in a physical structure. PUFs are implemented in integrated circuits, including FPGAs, and can be used in applications with high-security requirements, more specifically cryptography, Internet of Things (IOT) devices and privacy protection.