Online quizzes and practice questions, as well as other homework activities, will be linked to here as they become available.
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.
Refresh your knowledge of basic mathematics relevant for security (and data communications).
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.
In-class quiz on 10 Feb 2015.
Modular arithmetic, primes, Euler's totient.
This practice contains a mix of questions from previous quizzes. You may use it as practice for the midterm exam (however it doesn't mean the questions from this practice are necessarily in the exam, nor does it mean the exam doesn't include other types of questions). This practice is not assessed.
Authentication concepts, MACs, hash functions, digital signatures.
Key management and distribution.