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Lecture

Sybil Attacks and Defenses

In course

CS-438: Decentralized systems engineering

A decentralized system is one that works when no single party is in charge or fully trusted. This course teaches decentralized systems principles while guiding students through the engineering of their own decentralized system featuring messaging, file sha ...

Description

This lecture covers Sybil attacks and defenses in permissionless consensus systems, focusing on fake identities, virtual nodes, social bots, sockpuppets, astroturfing, fake reviews, and ballot stuffing. The instructor also discusses defenses such as strong identity verification, biometrics, and the need for privacy.

Instructors (2)

Bryan Alexander Ford

Pierluca Borsò

Official source

Related concepts (32)

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.

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.

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.

Astroturfing

Astroturfing is the practice of hiding the sponsors of a message or organization (e.g., political, advertising, religious, or public relations) to make it appear as though it originates from, and is supported by, grassroots participants. It is a practice intended to give the statements or organizations credibility by withholding information about the source's financial backers. The term astroturfing is derived from AstroTurf, a brand of synthetic carpeting designed to resemble natural grass, as a play on the word "grassroots".

Consensus (computer science)

A fundamental problem in distributed computing and multi-agent systems is to achieve overall system reliability in the presence of a number of faulty processes. This often requires coordinating processes to reach consensus, or agree on some data value that is needed during computation. Example applications of consensus include agreeing on what transactions to commit to a database in which order, state machine replication, and atomic broadcasts.

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