PUF – Physical Unclonable Functions

from historical banking and telecommunication applications to electronic passports, electronic IDs, anti-counterfeiting devices, smartgrid applications, and more. The security requirements for most of these applications are crucial and evolving. In addition, more and more sophisticated attacks are being developed every day. As a result, design of Smart Card ICs is a growing challenge. This paper summarizes the present-day security challenges for Smart Card ICs and describes how a special technology, called Physical Unclonable Functions (PUF), delivers comprehensive protection in today's applications. PUF technology provides a secure method for storing a key, withstanding today's attacks, and even protecting against future potential attacks. Note: For the purposes of this document, the term "Smart Card ICs" refers to microcontrollers based on smart-card secured technologies in traditional smart-card applications and in the secure elements of NFC-enabled devices, authentication tokens, and other high-security modules. The Smart Card industry typically places attacks in one of three categories:  Side channel attacks (non-invasive attacks) – such as using information out of the power profile or the electromagnetic emanation  Fault attacks (semi-invasive attacks) – such as disturbing the IC by applying laser light or a voltage glitch  Reverse engineering (invasive attacks) – reverse engineering parts of the IC, possibly combined with probing signals There has been important progress in all of these attack categories during the last few years. Smart Cards have to use sophisticated countermeasures to withstand these new attacks. In some markets, such as electronic passports, Smart Card ICs have to withstand attacks in the field for the ten years they are valid. Reverse engineering attacks are back in focus, especially after recent attacks on some widely used Smart Card ICs. These attacks often have a much higher impact than side channel and fault attacks because there are essentially no ways compensate for them with additional software countermeasures. Fault and side channel attacks are often carried out on a limited basis, on specific modules or portions of the device, and can be addressed with additional software countermeasures. There are several countermeasures available today that hinder reverse engineering and prevent attacks, and new technology nodes and more sophisticated techniques continue to improve security. But, in the end, given unlimited effort, there is an attack path for every chip. The reality is that there is no such thing as guaranteed protection. Typical reverse engineering attacks on Smart Card ICs include the following:  Reverse engineering of …