Exercises

This indicates the exercises that shall be covered in the (voluntary) exercise classes. You are are encouraged to try as many of them as you can (preferably before the class!) and ask the teaching assistant for help with those that you have difficulties with.

The Chapters are from the main book. Computer Problems in brackets should be possible to do even without a computer (possibly with some extra effort). The rest you can do using your favourite mathematical package.

  • Students that don't have the book: click here. Note that I will update these images of exercises every Thurs. or Friday and the old one's will be gone.
DateTopicBook ChapterExercisesComputer ProblemsAnswers
22/08 Classical ciphers
Number theory
2
3
1–6,9.
1,3,4(a),5(a).
1,3. Answers 1
30/08 Vigenere ciphers
Hill ciphers
2
3
10,13–18,24.
18,19.
Answers 2
05/09 Stream ciphers (LFSR) 2 19,20,21 Answers 3
12/09 Modular exponentiation
primitive roots & DH-KAP
3
7
12–14,17,21.
10, Ex1.
Answers 4
19/09 CRT
DL-problem
primarity test
3
7
6
9–10,24.
1,4–7
Ex2.

1,3.
Answers 5
3/10 RSA
Factoring
ElGamal
6
6
7
1,3,8,16–17.
12
11.
3,11.
4.
23/10 Digital signatures
Hash functions
9
8
5
1–4, 10.
1
30/10 Secret Sharing Schemes 12 1–2, 7–8.
2013-11-27, Øystein Ingmar Skartsæterhagen