Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

Censorship Resistance

In course

CS-523: Advanced topics on privacy enhancing technologies

This advanced course will provide students with the knowledge to tackle the design of privacy-preserving ICT systems. Students will learn about existing technologies to prect privacy, and how to evaluate the protection they provide. ...

Description

This lecture delves into the concept of censorship resistance, focusing on the technological strategies to make the internet accessible and usable despite attempts to block or control information flow. The instructor discusses the importance of privacy technologies, self-determination, freedom of speech, and information. Various systems and techniques such as decoy routing, covert channels, and encryption are explored to circumvent censorship. Examples like Tor, ScrambleSuit, and Telex are presented to illustrate how these systems work and the challenges they face. The lecture emphasizes the need for censorship resistance to ensure freedom of expression and access to information in the face of increasing online restrictions.

This video is available exclusively on Mediaspace for a restricted audience. Please log in to MediaSpace to access it if you have the necessary permissions.

Watch on Mediaspace

Instructors (2)

Carmela González Troncoso

Alessandro Chiesa

Alessandro Chiesa is a faculty member in computer science. He conducts research in complexity theory, cryptography, and security, with a focus on the theoretical foundations and practical implementations of cryptographic proofs that are short and easy to verify. He is a co-author of several zkSNARK libraries, and is a co-inventor of the Zerocash protocol. He has co-founded Zcash and StarkWare Industries. He is a recipient of a Sloan Research Fellowship (2021), an Okawa Foundation Research Grant (2020), and Google Faculty Research Awards (2018 and 2017). He was included in MIT Technology Review's "35 Innovators Under 35" list in 2018.

Official source

Related concepts (32)

Internet censorship

Internet censorship is the legal control or suppression of what can be accessed, published, or viewed on the Internet. Censorship is most often applied to specific internet domains (such as, for example, Wikipedia.org) but exceptionally may extend to all Internet resources located outside the jurisdiction of the censoring state. Internet censorship may also put restrictions on what information can be made internet accessible.

Internet censorship circumvention

Internet censorship circumvention, also referred to as going over the wall () or scientific browsing () in China, is the use of various methods and tools to bypass internet censorship. Various techniques and methods are used to bypass Internet censorship, and have differing ease of use, speed, security, and risks. Some methods, such as the use of alternate DNS servers, evade blocking by using an alternate address or address lookup system to access the site.

Freedom of speech

Freedom of speech is a principle that supports the freedom of an individual or a community to articulate their opinions and ideas without fear of retaliation, censorship, or legal sanction. The right to freedom of expression has been recognised as a human right in the Universal Declaration of Human Rights and international human rights law by the United Nations. Many countries have constitutional law that protects free speech. Terms like free speech, freedom of speech, and freedom of expression are used interchangeably in political discourse.

Onion routing

Onion routing is a technique for anonymous communication over a computer network. In an onion network, messages are encapsulated in layers of encryption, analogous to the layers of an onion. The encrypted data is transmitted through a series of network nodes called "onion routers," each of which "peels" away a single layer, revealing the data's next destination. When the final layer is decrypted, the message arrives at its destination. The sender remains anonymous because each intermediary knows only the location of the immediately preceding and following nodes.

Tor (network)

Tor, short for The Onion Router, is free and open-source software for enabling anonymous communication. It directs Internet traffic via a free, worldwide, volunteer overlay network that consists of more than seven thousand relays. Using Tor makes it more difficult to trace a user's Internet activity. Tor protects personal privacy by concealing a user's location and usage from anyone performing network surveillance or traffic analysis. It protects the user's freedom and ability to communicate confidentially through IP address anonymity using Tor exit nodes.

Related lectures (33)

Anonymity Online: Techniques and Weaknesses

Explores online anonymity techniques and weaknesses, including bypassing geo-blocking and avoiding tracking.

Anonymous Communications: Tor and Internet Privacy

Examines anonymous communications using Tor to protect privacy and navigate internet censorship, discussing its history, functionality, and limitations.

Anonymous Communication: Motivations and Approaches

Explores motivations for anonymous communication and various approaches to achieve anonymity.

Internet Capsules: Opportunities and Dangers

Explores the opportunities and dangers of the internet, including encryption, surveillance, and censorship.

Internet Capsules: Security and Privacy