Online quizzes and practice questions, as well as other homework activities, will be linked to here as they become available.

Quiz 1 - Security Concepts and Ciphers

a href="homework1">Homework 1 - Break Classical Ciphers (not marked)

Several ciphertexts are provided, as well as the algorithm used, but no key. Find the plaintext. This is not assessed, not required and may be time consuming. Don't attempt until you understand the topics covered in lecture. This homework is un-assessed (no marks for completing it, no penalty for not completing it).

Practice - Statistics for Security

Refresh your knowledge of basic mathematics relevant for security (and data communications).

Quiz 2 - Block Ciphers and Modes of Operation

Concepts of block ciphers; DES, Double DES and Meet-in-the-middle; Modes of operation. Some questions use the same example 5 bit block cipher covered in class. Having a printout in front of you while attempting the quiz may help. Also you should have a pen and paper available to solve some problems.

a href="homework2">Homework 2 - OpenSSL Encryption

a href="quiz3">Quiz 3 - Ciphers (In-class)

In-class quiz. Questions: a | b | c | d | e. Answers. See your grade and scanned copy of your quiz in your feedback.

Quiz 4 - Number Theory Basics

Modular arithmetic, primes, Euler's totient. Try to solve without a calculator.

Quiz 5 - RSA

a href="homework3">Homework 3 - Public Key Crypto

Quiz 6 - Authentication

Authentication concepts, MACs, hash functions, digital signatures.

Quiz 7 - Key Distribution

Key management and distribution.

Quiz 8 - HTTPS, SSL and Internet Security

HTTPS, SSL and Internet Security