Theoretical Computer Science – Cryptography and Computer Algebra

Cryptography is traditionally concerned with hiding information. Modern cryptography is also concerned with digital signature schemes, hash functions, identification schemes and much more. The SSL connection with your bank, the radio key of your car, or a software update, all have security requirements that are fulfilled behind the scenes using cryptographic schemes.

Our team works in different fields of modern cryptography. A large part of our group works on building cryptographic schemes that are secure in the presence of quantum computers that break the security of existing schemes like RSA. In this context we are also working on practical cryptanalysis, which allows us to propose secure sets of parameters for these schemes. Another part of our team is concerned with building secure e-voting schemes. Furthermore we are working on the long term security of cryptographic schemes and the usability of cryptographic software in general.


  • Number Theory
    • Algorithms for problems in algebraic number theory

  • Cryptography
    • development
    • implementation
    • formal verification
    • analysis, in particular for the age of quantum computers

  • Public-Key Infrastructures
    • ease of use
    • ease of integration into workflow
    • ease of cryptographic replacement
    • Usability Aspects


CROSSING – Cryptography-Based Security Solutions

CYSEC – Profilbereich Cybersicherheit

QUANTICOR – Post-Quantum Cryptography and Blockchain Solutions

CRYPTOPLEXITY- Kryptographie und Komplexitätstheorie

CRISP – Center for Research in Security and Privacy Darmstadt


Our Challenges: Lattice Challenge and SVP Challenge

Our Java Cryptography Library: FlexiProvider

Our Spin Off: FlexSecure