Courses offered by members of the cryptology and data security research group. Current courses are listed below. See also the past courses and the thesis projects.

Overview

Undergraduate level – Bachelor Informatik, University of Bern

Two yearly courses that introduce students to relevant areas in computer science and prepare for the advanced courses. Undergraduate courses are taught in German.

  • Diskrete Mathematik (Fall)

  • Algorithmen, Wahrscheinlichkeit und Information (Spring)

Graduate level – University of Bern and Joint Master in Computer Science

Topics span cryptology, security, distributed computing, privacy, and more.

Thesis projects

Spring 2022

  • Algorithmen, Wahrscheinlichkeit und Information (in German)

    Bachelor Informatik, University of Bern; KSL 451670; please register in ILIAS.

    Diese Vorlesung führt das Gebiet der randomisierten Algorithmen und probabilistischen Verfahren ein, welche heute in der Informatik eine grosse Rolle spielen. Darüber hinaus werden auch die Grundlagen der Informationstheorie und der Begriff der Entropie vorgestellt. Probabilistische Methoden und Analysen treten in vielen Gebieten auf, in der Kommunikation, in Machine Learning, zur Datenanalyse und in der Kryptologie. Nach einer Einführung in die Wahrscheinlichkeitsrechnung mit diskreten Ereignissen werden wichtige probabilistische Methoden und deren Analyse behandelt, so zum Beispiel Abschätzungen mittels Chernoff-Bounds und die probabilistische Methode. Randomisierte Algorithmen auf Graphen und in der Zahlentheorie werden diskutiert. Entropie als Informationsmass wird eingeführt und Methoden für Codierung und Datenkompression behandelt.

    Kurssprache ist Deutsch. Unterlagen sind in Englisch.

  • Distributed Algorithms

    University of Bern and Joint Master in Computer Science; KSL 454448; please register in ILIAS.

    This course provides an introduction to computing in a distributed environment without a central coordinator. It presents fundamental programming abstractions for distributed systems and fault-tolerant, highly available, and secure protocols that implement them. Important problems of distributed computing are discussed and influential impossibility results are shown. The central question of the course is how to tolerate uncertainty and adversarial influence, which may arise from network delays, faults, or malicious attacks in a distributed system. Topics include replication, quorums, reliable broadcast, distributed storage, consensus, Byzantine agreement, atomic broadcast, and notions of consistency arising in this setting. Applications to real-world systems will be presented, in the domain of cloud computing, cryptocurrencies, and blockchain systems.

  • Seminar: Cryptography and Data Security

    University of Bern and Joint Master in Computer Science; KSL 453835; please register in ILIAS.

    The seminar in cryptology and data security covers various relevant topics in the area and its contents will change from one semester to another. Typical subjects are cryptographic protocols, secure computation, privacy, distributed trust and blockchains. A seminar will start with an overview of the topic, where some basic principles are introduced. The main content will typically consist of interactive presentations by the participants, on the basis of the existing literature, ranging from classic research papers to recently developed systems. In addition, students as well as members of the cryptology and data security research group will present their own current work.

    Theme of the seminar in Spring 2022 (Details are available in ILIAS)

    Blockchain Privacy

    It is commonly known that data on the permissionless blockchain is publicly visible. Prominent blockchains like Bitcoin and Ethereum disclose the amount, fee, senders, and receivers of a transaction. As a result, users of these blockchains can be tracked and deanonymized based on their transaction history. Only the link between the users and the cryptographic keys that they control may be hidden.

    Apart from the public transaction data, also the underlying peer-to-peer network used by blockchain nodes reveals information and may be a target for attacking the privacy of users. In fact, several works have shown how a network adversary can successfully link users’ cryptocurrency addresses to their IP addresses.

    Practitioners and researchers alike have offered multiple privacy-enhancing solutions to address such limitations regarding privacy. These solutions often target one of the layers of a blockchain network, that is, either the *blockchain layer* dealing with transactions or the *network layer* dealing with sending messages, respectively.

    This seminar explores attacks on the privacy of blockchains and (proposed or implemented) solutions for enhancing privacy. These either address the network layer or the blockchain layer of cryptocurrencies, smart-contract platforms, and blockchain networks.

    Participants will:

    • Choose one topic or system;
    • Develop a sample application with the system or describe the topic or system in a report;
    • Present their work.


  • Seminar Law and Computer Science: Distributed Trust in Finance

    University of Bern, Master of Law and Joint Master in Computer Science; KSL 475009; ILIAS link.

    Prof. Dr. Mirjam Eggen, Zivilistisches Seminar
    Prof. Dr. Christian Cachin, Institut für Informatik
    Dr. Christian Sillaber, Zivilistisches Seminar

    This interdisciplinary seminar is offered jointly by the Institute for Civil Law and the Institute of Computer Science. Students of computer science and law will work closely together on questions that arise from tensions between the progressing digitalization of the world and the existing law. Participants will work in interdisciplinary groups, and each group addresses one specific problem from a legal perspective and from a technical perspective. The goal is to provide assessments and to develop solutions for the problem from both perspectives.

    The topic of the seminar in Spring 2022 will be distributed trust in finance. Recent progress in blockchain technology and cryptocurrencies has led to new forms of financial instruments, markets, exchanges, and services. Those structures are realized only through open-source protocols on public networks, without real-world or legal intermediaries. This field is often summarized as Decentralized Finance (DeFi). Dozens of billions (in CHF) have been invested into Decentralized Finance so far.

    Information event: 15 December 2021, 17:30h, online. Please register to participate.

    See the information sheet for details.

    • Schedule
      • Information Session: 15.12.2021, 17.30h
      • Start of the registration period: 15.12.2021, 18.00h
      • Seminar days: 25.02.2022, 13.00h - 16.00h and 13.05.2022, ca. 08.30 - 17.00h


    There are still some free slots available for students in Computer Science. If you are interested to participate, please contact Christian Cachin by email until 21 February 2022.

Fall 2021

  • Diskrete Mathematik (in German)

    Bachelor Informatik, University of Bern; KSL 11479; please register in ILIAS.

    Diese Vorlesung führt in diskrete Mathematik ein und behandelt eine Reihe von zentralen Methoden und Konzepten, welche wichtig sind für das tiefere Verständnis der Informatik. Diskrete Mathematik ist ein Teilgebiet der Mathematik, das sich hauptsächlich mit endlichen und abzählbaren Strukturen beschäftigt. Zuerst werden Grundlagen der Logik eingeführt, insbesondere Aussagenlogik und Prädikatenlogik. Wichtige Themen sind danach Mengen, Relationen und Funktionen. Es folgen Themen aus Algebra und Zahlentheorie, welche auch für kryptographische Verfahren oder Codierungstheorie die Basis bilden. Darüber hinaus werden Konzepte aus der Graphentheorie vorgestellt. Die Vorlesung dient der Vorbereitung auf weitergehende Themen der theoretischen Informatik, wie Berechenbarkeit, Komplexität, Effizienz und probabilistische Algorithmen.

    Kurssprache ist Deutsch. Unterlagen sind in Englisch.

  • Privacy and Data Security

    University of Bern and Joint Master in Computer Science; KSL 471352; please register in ILIAS.

    The reliance of the information society on pervasive networks, mobile computing, online services, and cloud platforms continues to grow. The privacy of human activities and the security of personal data are challenged by today’s information technology in ways never seen before in history. This course focuses on privacy and security in a digital world. It presents cryptographic and non-cryptographic methods relevant for protecting privacy, anonymity, and data security. Topics include pseudonymity, data anonymization and de-anonymization, notions of privacy and privacy regulation, measures for the privacy of data, steganography and traffic hiding, network anonymity, and censorship resistance. Systems like onion routing (TOR) and Freenet are presented. Knowledge in computer science and networking is needed, but no background in cryptography is expected.

  • Seminar: Cryptography and Data Security

    University of Bern and Joint Master in Computer Science; KSL 453835; please register in ILIAS.

    The seminar in cryptology and data security covers various relevant topics in the area and its contents will change from one semester to another. Typical subjects are cryptographic protocols, secure computation, privacy, distributed trust and blockchains. A seminar will start with an overview of the topic, where some basic principles are introduced. The main content will typically consist of interactive presentations by the participants, on the basis of the existing literature, ranging from classic research papers to recently developed systems. In addition, students as well as members of the cryptology and data security research group will present their own current work.

    Theme of the seminar in Fall 2021

    Advances in blockchain technology: From Layer 1 to Layer 2

    Blockchain networks power cryptocurrencies and enable automated decentralized-finance (DeFi) solutions through smart contracts. These protocols rely on cryptography and on algorithms for distributed consensus. The pioneering systems, Bitcoin and Ethereum, are too slow to support the transaction workload envisaged for the future.

    Several next-generation blockchain protocols have become prominent and aim at addressing this issue by replacing the core protocols. These solutions are said to work on “Layer 1” or “L1”, which is the core protocol that defines the security of a network. Such protocols rely on proof-of-stake consensus, for example.

    Other solutions enhance blockchain networks outside the core protocols, at the so-called “Layer 2” or “L2”. Typically they rely on the core protocol and on the state maintained at L1 for their security, but enhance the functionality and speed of a network.

    This seminar explores recent advances blockchain technology that tackle scalability, interoperability, and more.

    Topics:

    • Next-generation blockchain protocols (L1)
      • Algorand, smart contracts on Algorand
      • Cardano, smart contracts on Cardano
      • Decentralized storage: Filecoin
      • Sharding and proof-of-stake in Ethereum 2.0
    • Blockchain scalability (L2)
      • Payment channels for Bitcoin: Lightning network
      • Scaling through parachains: Polkadot
      • Optimistic rollups: Offchain Labs Arbitrum
      • Zero-knowledge rollups: StarkWare
    • Infrastructure for decentralized finance
      • Oracle networks: Chainlink
      • Inter-blockchain communication
      • Internet of blockchains: Cosmos and the Cosmos Hub

Earlier semesters

  • Past courses

    Information about courses in earlier semesters can be found in the archive.