Cryptography (25S)

  1. Lecture/Course

    Cryptography

  1. Course Leader:
    Dipl.-Ing. Dr. Jasmin Wachter, BSc, BA
    Dates & Exam Information:
    See ZEUS Website for individual dates and further details.
    Description:
    This course offers a rigorous introduction to modern cryptography. It provides a theoretical and practical understanding of cryptographic systems, with a focus on formal definitions and security guarantees. Students learn to critically engage with the role of assumptions (computational hardness assumptions) and their impact on the security of cryptographic systems.

    Topics include:
      • Symmetric encryption, pseudorandomness, pseudorandom generators, pseudorandom functions
      • Stream ciphers, block ciphers
      • Message Authentication Codes, secure hash functions, and their construction principles
      • Public-key cryptography and digital signatures, padding

    The essential foundations of complexity and number theory as building blocks for cryptographic algorithms are also covered. In particular, the theory is illustrated and explained using existing as well as already obsolete cryptographic methods.
    Expected Prior Knowledge:

    There are no formal access restrictions, but the course builds on knowledge in the following areas:
      • ESOP or programming skills are required
      • Basic systems security (CIA+)
      • Algorithms and data structures (Big-O notation, binary/hexadecimal arithmetic, XOR)
      • Discrete mathematics (residue class rings, groups, fields)
      • Stochastics (elementary combinatorics and probability theory, Bayes' theorem, total probability)

    Course Materials:

    See Moodle Course
    "Introduction to Modern Cryptography" by J. Katz and Y. Lindell (in the textbook collection, 3rd edition)
  1. Course Chapters

    1. Symmetric Encryption and Perfect Security
    2. Security as a Game Between Attacker and Defender: Semantic Security
    3. Pseudorandomness and Security Reduction Proofs
    4. CPA Security and Block Ciphers
    5. CCA Security and Malleability
    6. Message Integrity: MACs
    7. Substitution-Permutation Networks
    8. Hash Functions and Collision Attacks
    9. Number Theory and Groups
    10. Public Key Crypto: from RSA to ElGamal