Public Key Cryptanalysis I

Undergraduate / Graduate course, Ruhr University Bochum

offered by Prof. Dr. May

Corrector (2023)

Course Description

Cryptanalysis is used to instantiate cryptographic systems in such a way that they offer a predefined level of security on the one hand, but are as performant as possible on the other. Cryptanalysis offers a whole toolbox of algorithmic techniques to realise the evaluation of new cryptographic systems. This includes classical algorithms as well as algorithms for quantum computers, so that the cryptography used remains secure even in an era of quantum computers.


Students will gain broad knowledge of algorithmic techniques for asymmetric cryptanalysis, particularly for code-based cryptography. After successful completion of the module students

  • know basic key-finding algorithms such as brute-force and meet-in-the-middle and can apply them to new cryptographic systems,
  • know the basics of linear codes and their dual codes, in particular the McEliece cryptosystems as a cryptographic application,
  • know time-memory techniques such as Pollard Rho and Parallel Collision Search, and can apply them to new problems,
  • have an overview of all current decoding algorithms in the field of information set decoding that are relevant for the security evaluation of modern code-based cryptosystems,
  • are able to implement techniques of cryptanalysis using the computer algebra Sage.