3 Circuit approaches to Physical Cryptography

Nowadays keeping information safe is one of the most important research topics in Computer Science and Information Technology. Consequently, many techniques of Cryptography and Security are continually being proposed. In this thesis we will investigate a novel approach to Cryptography, Physical Cryptography: This suggests the application of optical and electrical nanostructures to cryptography and security, to complement standard, algorithmic procedures. Using physical objects enables security solutions with novel features. This thesis focuses on the introduction and analysis of two specific techniques related to Physical Cryptography: SHIC (Super High Information content) systems allow the user to keep a high amount of information safe from external attacks: The architecture of these circuits forces an extremely slow-read out of the data. This specific characteristic prevents the system from being completely characterized by the attacker when this has gained temporal access to the circuit. UNIQUE objects are the other field to study in this work: Here, only small amount of information is protected. Its fast internal speed makes it physically impossible to being reproduced or imitated by an intruder. We will present two techniques and propose possible physical circuits that implement SHIC and UNIQUE: SPICE and Sentaurus TCAD simulators will be used for making analog-circuit and device-level simulations respectively, in order to study and conclude the feasibility of both proposals. 4