This week you will learn the fundamentals about physical attacks: what are physical attacks, who are the attackers, what are their motivations, how can they attack your system (from hardware), what kind of skills/tools/equipment they should need to break your system, etc. You will also see what are the available countermeasures. You will learn how system security level and tamper resistance level are defined and some general guidelines on how to make your system secure by design. In the second part, you will learn a useful mathematical operation called modular exponentiation. It is widely used in modern cryptography but it is very computational expensive. You will see how security vulnerability might be introduced during the implementation of this operation and thus make the mathematically sound cryptographic primitives breakable. This will also be important for you to learn side channel attack next week.