Physical Unclonable Functions for enhanced security of tokens and tags

Security tokens and RFID-tags are playing an increasingly important role in the authentication of persons and devices, e.g. controlling access to services and protecting the value of goods and digital content. In order to provide the required security level they are used in combination with a cryptographic algorithm. State of the art algorithms are so sophisticated nowadays that they are virtually immune against mathematical attacks. Hence, the offered security level essentially depends on the secrecy of the employed keys. Several studies have shown that the secrecy of keys stored in memory is not guaranteed when physical attacks are used.