QCS: Quantum Cyber Security

On successful completion of this course, you should be able to: 

1. demonstrate their understanding of the power and limitations of quantum computation by evaluating the performance of quantum algorithms and be able to use the basic mathematical formalism for quantum information and quantum cryptography
2. test whether a classical cryptosystem is secure against a range of quantum attacks
3. analyse quantum attacks to classical protocols
4. demonstrate their understanding of the security of quantum cryptography by analysing the security proofs including the effects of different physical implementations
5. use security notions for quantum information, such as encryption and authentication, in quantum cryptographic protocols and their application to blind quantum computation

This course deals with the various effects that developing quantum technologies will have on cyber security. Quantum computing and quantum information theory offers new possibilities (in terms of efficiency and security). Here we examine both the extra attacks that adversaries equipped with quantum technologies can perform and the extra possibilities opened when honest parties use quantum technologies.

The students first will be introduced to quantum information concepts (qubits, mixed states, operations, distance measures) as well as quantum algorithms (factoring, discrete logarithms, search) and their limitations. This will lead to LO1, namely learn the mathematical machinery and the power (and limitations) of quantum information and computation, in view of using these for cyber security.

The second part consists of learning and understanding quantum cryptography and specifically "quantum-key-distribution" protocols, including their security proofs and the how different implementations affect the performance (see LO4). The limitations (practical and theoretical) of quantum cryptography will also be analysed here (including impossibility results).

The third part deals with generalising classical notions such as encryption, authentication and secure delegated computation to quantum information. Introducing students in these concepts prepares them for the next generation of quantum cyber security that is bound to become relevant when large(r) quantum computers are constructed (LO5).

Finally, the last part of the course focuses on classical protocols and their security under quantum attacks. A cryptosystem based on the learning-with-errors problems will be introduced as a (key) example of this possibility (LO2). Furthermore, general quantum attacks (superposition attacks, the quantum random oracle model, etc) will be introduced and students will learn to analyse general quantum attacks on a given classical protocol (LO3).