News

Recordings online & Tomorrow's in-person lecture

Written on 28.04.25 by Wouter Lueks

Dear all,

the recordings for Lecture 3 are available since this morning - we’re sorry for the delay. Tomorrow’s lecture will be in person in the CISPA lecture hall again. After recording 2+ hours by myself and the very interactive (!) zoom session 2 weeks ago, I’m really looking forward to seeing… Read more

Dear all,

In the mean time, here is the flow-chart for which recordings to watch for tomorrow:

If you have no time to watch the recordings for tomorrow: don’t worry, I’ll try to make things accessible.
If you do have some time, and did not encounter basic public-key crypto in your studies, we strongly suggest that you watch the crypto refresher part to make sure you are at least up to date on the Groups and Fields — that will make tomorrow’s lecture easier to digest.
If you have even more time, please also watch the zero-knowledge lecture to make sure you know all the background for tomorrow. However, you will be perfectly fine without having watched it, I will repeat the key conclusions.

In any case, all recordings of the Lecture 3, but in particular the zero-knowledge parts, are essential for Project 2, which will also be released tomorrow.

Looking forward to seeing many of you again tomorrow!

Cheers,
- Wouter

Today's Lecture Online

Written on 15.04.25 by Wouter Lueks

Hi everyone,

today's lecture and exercise will be held online only starting at 14:15. Please use the Zoom link in the Materials section (Week 02) of the CMS.

I really enjoyed the interactions last week, and hope to see all of you online today. As always, we will record only the lecture. There… Read more

Hi everyone,

today's lecture and exercise will be held online only starting at 14:15. Please use the Zoom link in the Materials section (Week 02) of the CMS.

I really enjoyed the interactions last week, and hope to see all of you online today. As always, we will record only the lecture. There will be no recording of the following exercises/discussion. Participating in these exercises is essential in preparing your for the exam. We therefore strongly recommend attending the lecture and exercises live.

Cheers,
- Wouter

Project 1 Release

Written on 15.04.25 by Tim Rausch

Hi everyone,

the first project will be released today. There will be a brief introduction in today's lecture and we will release the project description afterwards.

The project code will be distributed via a Git repository and you must submit your solutions to the same repository as… Read more

Hi everyone,

the first project will be released today. There will be a brief introduction in today's lecture and we will release the project description afterwards.

The project code will be distributed via a Git repository and you must submit your solutions to the same repository as follows:

1. Login to https://lab-pets.privacy-preserving.systems with your CMS credentials (via the Login with GitHub button).
2. Once logged in, wait while the system initialises your repository automatically. This may take up to 15 minutes.
3. Verify that you have been granted access to a repo named pets25-h-[0-9|A-Z]+, and that this repo contains a project1 branch. On this branch, you will find the skeleton code for project 1.
4. Create a personal access token or upload your SSH key.
5. You can now clone the repository and start working on your code. You can push and save progress to the project1 branch at any time. Testing pipelines will run automatically after each push.
6. Submit your code to project1-submission branch. This branch does not exist by default, so you need to branch out locally and push it to your repo. Remember that this branch will be protected and you cannot force push to it:

$ git checkout -b project1-submission
$ git push origin projet1-submission

Feel free to already log in to the Gitlab, but we highly recommend only starting to work on the project after it was presented during today's lecture.

Privacy-Enhancing Technologies

Digital technologies have become an essential part of our day-to-day lives. While often beneficial, these technologies also bring great privacy risks. In this course, you will learn how to mitigate these risks by designing privacy-friendly systems and how to evaluate the privacy protections offered by systems.

To reason about the privacy of systems you will learn how to define desirable privacy properties and how to reason about privacy attackers. Privacy can be violated both at the application level (i.e., what data parties exchange) as well as on the meta-data level (i.e., how parties exchange data). You will learn about techniques to offer protection at both of these layers.

On the application layer, we’ll discuss cryptographic techniques such as secure multi-party computation, homomorphic encryption, and anonymous authentication that together can be used to ensure privacy at the application layer. We will also discuss data anonymisation techniques such as k-anonymity and differential privacy to enable privacy-friendly data publishing. On the meta-data level, we’ll explore techniques for anonymous communication, censorship resistance, (browser) tracking, and location privacy.

At the end of this course you will be able to:

Explain basic building blocks for designing privacy-friendly systems
Combine these building blocks to solve simple problems while maintaining privacy
Evaluate the privacy of simple proposed systems.

Prerequisites

The privacy-enhancing technologies class is an advanced lecture. You will learn a lot about how to design and analyse privacy-friendly systems, but this is not an easy 6EC course. A basic understanding of security and cryptography (as taught for example in CySec1/CySec2 or the Security course) is essential to be able to follow the material in this course. If you have not mastered this material we strongly recommend you to take this course next year instead.

Schedule

Main Lecture: Tuesday from 2pm c.t. to 4pm
Exercises/Discussion: Tuesday from 4pm s.t. to 5pm
Room: E9.1 (CISPA building), room 0.05 (main lecture room)

Schedule

The following schedule is subject to small changes.

April 8: Introduction to Privacy
April 15: Secure Multi-Party Computation (remote)
April 22: Crypto Recap + Zero-knowledge Proofs (recorded)
Apr 29: Attribute-Based Credentials
May 6: Tracking
May 13: Fully-Homomorphic Encryption
May 20: Anonymous Communication
May 27: no class
June 3: TBD
June 10: Censorship Resistance
June 17: Anonymization / Protected Data Release
June 24: Differential Privacy

Format

The course will be hybrid, but attending the lectures and exercise sessions is strongly recommended for UdS students. Attending online only possible in exceptional cases. We will publish recordings of the lectures. We will not publish recordings of the exercise/discussion sessions. Learning to reason about privacy is difficult. We strongly recommend that you attend the exercise/discussion sessions to practice your reasoning skills.

Exercise Class / Office Hours

We offer office hours to answer questions regarding the content of the lecture, exercise sheets, and projects. Feel free to drop by in person or remotely if you have any questions.

In Person

Times: Wednesday, 3pm s.t. -- 4pm
Location: CISPA building (E9.1), Room 1.02

Remote

The remote office hours are primarily intended for those who cannot attend the in-person office hour. Please book a time slot in advance via the sheet linked in the Materials section.

Times: Wednesday, 2pm s.t. -- 3pm
Location: Zoom (Link in Materials section)

Grading

The final grade for this course consists of 60% for the final exam and 40% for the projects.

Grading subject to small changes. Details will be explained in the first lecture.

Projects

As part of this class you will work on three projects to implement and evaluate a privacy-preserving system. The projects contribute 40% to the final grade: 10% for the first project and 15% for each of the second and third projects. There is no option to improve the grade for the projects.

Final Exam

Exam date: August 1, 2025, 9:30am s.t. -- 11:30am
Format: Written exam
Location: tbd

The final written exam tests your understanding of the material covered in the class, exercises, and projects. You must receive a passing grade on the exam alone. If you do, the exam is graded and contributes 60% to the final grade.

The re-exam will take place on:

Exam date: September 19, 2025, 9:30am s.t. -- 11:30am
Format: Written Exam
Location: tbd