Dr. Nicolas T. Courtois – Research Interests

Research Interests – Crypto Currencies:

    • All topics in Bitcoin, Ethereum, Darkcoin etc.
    • How to speed up the hashing process with SHA256.
    • How to steal bitcoins with SHA256+secp256k1+BIP032 etc.
    • The Longest Chain Rule and programmed self-destruction of crypto currencies.
    • Hash rate vs. security.
    • 51% attacks and Double Spending attacks.
    • Monetary policy.
    • Regulation, backdoors, dark side of open source software.

Research Interests – Cryptology:

  • Computational cryptanalysis of symmetric and asymmetric ciphers.
    • Algebraic Attacks: recover the secret key of a cipher by solving a very large
      system of multivariate equations over small finite fields.

      • Special properties that make systems efficiently solvable (e.g. sparsity).
      • Conversion and solving algebraic equations with SAT solvers.
      • Computing Gröbner bases and designing simpler and frequently much
        better/faster algorithms: Gröbner basis require a fixed polynomial ordering. In
        many real-life cryptanalysis problems this is a VERY bad idea
        and better results are obtained with ad-hoc elimination
        algorithms which optimize sparsity such as ElimLin
        (and its practical implementations which take care of sparsity).
    • Design and feasability of algebraic attacks: for example some stream ciphers
      will be broken if a certain multivariate polynomial equation exists (sometimes
      finding one such equation is sufficient to break the cipher!). Cryptanalysis of
      some block ciphers greatly depends on whether they can be written in a certain

      • Define what kind of equations are useful/interesting. Find out if such
        equations exist, prove they exist (or not), compute these equations.
      • Can AES be broken?
    • Experimental algebraic cryptanalysis.
      • Automation of symmetric cryptanalysis. Finding special properties of ciphers.
      • Implementation of algebraic attacks. Manipulating very large systems of
        multivariate equations. Fast linear algebra, in particular when RAM is scarce.
        Specialised memory management, parallel computing, use of specialised hardware.
    • Number theory and lattices.
    • Side channel attacks on smart cards.
    • Russian and Soviet cryptography.
  • Post-quantum cryptography and very efficient public key schemes for special

    • Very short digital signatures (that can be transmitted or and verified with
      human interaction). Unforgeability and third-party verifiable authenticity of
      paper documents (bank notes, cheques, ID cards, electronic airline tickets,
    • Very fast digital signatures (much faster than RSA) for low-cost devices.

Research Interests – Information Security:

  • Computer Security
    • All topics! I used to teach Computer Security at UCL: here are my slides.
    • I have always insisted that computer security is obtained by combination of hardware and software.
  • Markets and Information Security:
    • Security in complex commercial systems. For example electronic bank cards +
      terminals + back-end applications + supporting infrastructure+ user
      adoption + usability + legal and regulatory drivers + economics + fraud + crime
      science + moral and ethical considerations. Compliance.
    • Smart cards and smart card protocols.
    • Proprietary cryptography.
    • Crypto currencies.
    • Economics of security, prices, bets and future markets in information security.
    • Risk management. Fraud in financial markets and financial institutions.
      Data security and compliance in financial institutions.


  1. Dear Dr. Nicolas T. Courtois
    Dear Dr.Nicolas can i ask you if you can supervise me in my PhD research, because i have a full scholarship from the higher committee for education development (HCED),under the auspices of the office of the prime minister of Iraq.
    i am interested in cryptography and you have wide experience in this subjects,i have a research proposal but i am ready to accept any ideas or research from you.
    Please Dr. Nicolas, i hope that you accept to supervise me.

    Best Regards

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