Teaching Portfolio

The following table summarizes our teaching portfolio.

Type/Branch Summer Term ECTS Winter term ECTS
Basic class Introduction to Algorithms 7.5 Introduction to Modern Cryptography 7.5
Cryptocurrencies Cryptocurrencies I 5 Cryptocurrencies II (from winter term 23/24) 5
Privacy Data Privacy I 5 Data Privacy II (from winter term 23/24) 5
(by Prof. Rösler)
Cryptographic Communication Protocols (Lecture) 5 Cryptography in Secure Messaging: Understanding and Enhancing Signal (Seminar) 5
Seminar Selected topics 5 Selected topics 5
Project Privacy and Crypto 10 Privacy and Crypto 10
i13 seminar doctoral seminar 5 doctoral seminar 5
Introduction to Algorithms

This lecture provides a thorough introduction to the fields of algorithms and data structures. This introduction covers basic design concepts of algorithms and their formal analysis. The following topics are covered: Design and analysis of algorithms, correctness of algorithms, growth functions, recurrence, probabilistic algorithms and their analysis, basic algorithms and data structures and their formal analysis, sorting algorithms, graph algorithms, algorithms in number theory and string matching, matrix operations, and selected topics.

Introduction to Modern Cryptography

This (core) course gives a comprehensive introduction to modern cryptography and covers topics such as information-theoretic security, computational security, private-key encryption, message authentication codes, hash functions, public-key cryptography, and digital signature schemes.

Data Privacy

The specialization “Data Privacy” consists of two parts: The first part focuses on private data access and the second part on privacy-preserving computation on data. Each part includes recent research results developed by the group and me.

Part I: Private data access, reconstruction attacks, private-information retrieval, oblivious RAM, and oblivious group ORAM.

Part II: Basic anonymization techniques, i.e., k-anonymity, k-closeness, l-diversity, and their limitations. Differential privacy, differential privacy and machine learning. Alternative approaches such as homomorphic encryption.


The specialization “Cryptocurrencies” is divided in two parts: The first part covers the basics such as the formalization of the blockchain and the second part focuses on privacy-preserving cryptocurrencies. These lectures contain recent research results developed by the group and me.

Part I: Introduction to cryptocurrencies and Bitcoin, the Bitcoin backbone protocol, application and limitations of Bitcoin, i.e., payment channels and anonymity.

Part II: Proof systems, privacy-preserving cryptocurrencies, confidential transactions, Monero, and Zcash.

Messaging (by Prof. Rösler)

Cryptographic Communication Protocols: Key Exchange and Channels (Lecture): The goal of this lecture is to introduce standard cryptographic tools and methods that are used to build secure key exchange and communication channels. Starting with simple encryption protocols, the lecture will end with modern communication protocols that are implemented in messenger apps like Signal and WhatsApp.

Cryptography in Secure Messaging: Understanding and Enhancing Signal (Seminar): The purpose of this seminar is to obtain an overview of modern messaging protocols used in applications like WhatsApp and Signal. During the seminar course, we consider scientific publications that analyze Signal’s Double-Ratchet protocol, publications that propose enhancements for it, and publications that investigate the strongest possible security messaging protocols can theoretically provide.


The project is a practical class in which the students implement and evaluate concepts and methods in privacy and cryptography. As an example consider the ongoing project VisualAnon. This project follows our research about the anonymity of fitness apps that showed at the example of Germany how considerably the anonymity decreases by the leakage of socio-democratic data. The goal of VisualAnon is to cause awareness about the anonymity set people live in, not only for Germany but for arbitrary countries.


I offer a seminar on changing topics every semester. These topics are in line with the current research interests in IT security, privacy, and cryptography. In recent semesters, a seminar has been offered on the following topics: Privacy, Recent Advances in Cryptography, and Privacy and Legal Aspects of Immutable Blockchain.

Overall structure of the lectures

The ideal starting point to deepening the studies in the area of privacy and cryptography is the winter term, in which I offer an introductory lecture to modern cryptography. Students may continue their studies with data privacy I and/or cryptocurrencies I in the summer term and attend the second part of each lecture in the winter term.

If a student wishes to start in the summer term, then beginning with cryptocurrencies I or data privacy I is possible. Both lectures only require some basics in cryptography, which will be introduced in the first lecture. Then, in the winter term, the students can take the classes introduction to modern cryptography and data privacy II/cryptocurrencies II in parallel.