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Lecture

Sybil Attacks and Defenses

In course

CS-234: Technologies for democratic society

This course will offer students a broad but hands-on introduction to technologies of human self-organization. ...

Description

This lecture covers Sybil attacks in the context of the Tor network and distributed hash tables, discussing the creation of fake content and the use of social bots to spread fake news. It also explores the impact of Sybils on the believability of online content. The instructor delves into strategies to defend against Sybil attacks, including detection, analysis, and the use of AI/ML. The lecture concludes with a discussion on the Proof of Personhood concept, emphasizing the importance of strong identity verification methods like face verification and unique identifiers.

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Instructors (2)

Bryan Alexander Ford

Verónica del Carmen Estrada Galiñanes

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Related concepts (32)

Fake news

Fake news is false or misleading information presented as news. Fake news often has the aim of damaging the reputation of a person or entity, or making money through advertising revenue. Although false news has always been spread throughout history, the term "fake news" was first used in the 1890s when sensational reports in newspapers were common. Nevertheless, the term does not have a fixed definition and has been applied broadly to any type of false information.

Distributed hash table

A distributed hash table (DHT) is a distributed system that provides a lookup service similar to a hash table. Key–value pairs are stored in a DHT, and any participating node can efficiently retrieve the value associated with a given key. The main advantage of a DHT is that nodes can be added or removed with minimum work around re-distributing keys. Keys are unique identifiers which map to particular values, which in turn can be anything from addresses, to documents, to arbitrary data.

Fake news website

Fake news websites (also referred to as hoax news websites) are websites on the Internet that deliberately publish fake news—hoaxes, propaganda, and disinformation purporting to be real news—often using social media to drive web traffic and amplify their effect. Unlike news satire, fake news websites deliberately seek to be perceived as legitimate and taken at face value, often for financial or political gain. Such sites have promoted political falsehoods in India, Germany, Indonesia and the Philippines, Sweden, Mexico, Myanmar, and the United States.

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.

Sybil attack

A Sybil attack is a type of attack on a computer network service in which an attacker subverts the service's reputation system by creating a large number of pseudonymous identities and uses them to gain a disproportionately large influence. It is named after the subject of the book Sybil, a case study of a woman diagnosed with dissociative identity disorder. The name was suggested in or before 2002 by Brian Zill at Microsoft Research. The term pseudospoofing had previously been coined by L.

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