Introductory description

Cryptography is an essential tool in modern cyber security. It allows us to protect sensitive information, authenticate users and devices, and enable secure communication over insecure networks. Cryptographic techniques are used in a wide range of contexts, including secure messaging, protecting online transactions, and virtual private networks (VPNs). This module provides an introduction to the fundamental concepts of symmetric-key and public-key cryptography, and their practical applications.

Module aims

Outline syllabus

This is an indicative module outline only to give an indication of the sort of topics that may be covered. Actual sessions held may differ.

Introduction to cryptography:

• Why do we need cryptography?
• Historical encryption schemes

Symmetric-key encryption:

• Block ciphers: DES, 3DES, AES
• Stream ciphers and block cipher modes of operation
• The key exchange problem

Public-key encryption:

• RSA and elliptic curves
• Hybrid-key encryption
• Public-key infrastructure (PKI) and key authentication

Hash algorithms:

• Algorithms: MD5, SHA
• Applications: Authentication, known good/bad files, file integrity
• Known weaknesses: Attacks including brute force, rainbow tables and length extension attacks

Message authentication:

• Message authentication codes (MACs)
• Digital signatures

Important protocols:

• TLS and X509 certificates
• Secure communication protocols such as PGP and Signal
• Privacy-enhancing technologies such as DP-3T and Nym

The future of cryptography:

• Overview of blockchains and cryptocurrencies
• Introduction to post-quantum cryptography

Learning outcomes

By the end of the module, students should be able to:

• Identify and explain commonly used cryptographic primitives and protocols
• Analyse and critically evaluate the properties of different cryptographic algorithms
• Design secure cryptosystems that align with specific application requirements
• Evaluate the effectiveness and suitability of different cryptographic techniques in constructing cryptosystems

Indicative reading list

Wong, D., 2021. Real-World Cryptography. Manning Publications.

Anderson, R., 2021. Security Engineering. Wiley.

Schneier, B., Kohno, T. and Ferguson, N., 2013. Cryptography Engineering: Design Principles and Practical Applications. Wiley.

View reading list on Talis Aspire

Interdisciplinary

Cryptography is an inherently interdisciplinary subject. It combines ideas from mathematics, electronics and computer science together with social studies on the usability of secure systems, and these will be demonstrated throughout the module.

Subject specific skills

This course enables students to develop an understanding of the fundamentals of cryptography, knowledge of cryptographic algorithms and when to use them, as well as an ability to use cryptography to build secure systems.

Transferable skills

Critical thinking, problem solving, written communication skills, and the ability to independently build large, secure systems