Wei Dai ( zh, c=戴伟) is a computer engineer known for contributions to cryptography and cryptocurrencies. He developed the

Crypto++ Crypto++ (also known as CryptoPP, libcrypto++, and libcryptopp) is a free and open-source C++ class library of cryptographic algorithms and schemes written by Wei Dai. Crypto++ has been widely used in academia, student projects, open-source, and no ...

cryptographic library, created the b-money cryptocurrency system, and co-proposed the VMAC message authentication algorithm. The smallest subunit of

Ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again ...

, the ''wei'', is named after him.

Education and career

Dai graduated from the

University of Washington The University of Washington (UW, simply Washington, or informally U-Dub) is a public research university in Seattle, Washington. Founded in 1861, Washington is one of the oldest universities on the West Coast; it was established in Seatt ...

with a degree in computer science and is described as an "intensely private computer engineer". Wei Dai was member of the

Cypherpunk A cypherpunk is any individual advocating widespread use of strong cryptography and privacy-enhancing technologies as a route to social and political change. Originally communicating through the Cypherpunks electronic mailing list, informal g ...

Extropians Extropianism, also referred to as the philosophy of extropy, is an "evolving framework of values and standards for continuously improving the human condition". Extropians believe that advances in science and technology will some day let people l ...

, and SL4 mailing lists in the 1990s. On SL4 he exchanged with people such as Eliezer Yudkowsky, Robin Hanson,

Nick Bostrom Nick Bostrom ( ; sv, Niklas Boström ; born 10 March 1973) is a Swedish-born philosopher at the University of Oxford known for his work on existential risk, the anthropic principle, human enhancement ethics, superintelligence risks, and the ...

Aubrey de Grey Aubrey David Nicholas Jasper de Grey (; born 20 April 1963) is an English author and biomedical gerontologist. He is the author of ''The Mitochondrial Free Radical Theory of Aging'' (1999) and co-author of ''Ending Aging'' (2007). He is known ...

Anders Sandberg Anders Sandberg (born 11 July 1972) is a Swedish researcher, futurist and transhumanist. He holds a PhD in computational neuroscience from Stockholm University, and is currently a senior research fellow at the Future of Humanity Institute at t ...

, Eric Drexler, David Pearce, Hal Finney, and others in the nascent " rationalist" community.

Cryptography

Dai has made several contributions to the field of cryptography and has identified critical Cipher Block Chaining (CBC) vulnerabilities affecting SSH2 and the browser exploit against SSL/TLS known as BEAST (Browser Exploit Against SSL/TLS).

Crypto++

In June 2015 Dai stepped away from the Crypto++ project to work on other projects. Crypto++ is now maintained by the Crypto++ community.

VMAC

VMAC is a block cipher-based message authentication code (MAC) algorithm using a universal hash proposed by Ted Krovetz and Wei Dai in April 2007. The algorithm was designed for high performance backed by a formal analysis.

b-money

In 1998, Dai helped to spark interest in

cryptocurrencies A cryptocurrency, crypto-currency, or crypto is a digital currency designed to work as a medium of exchange through a computer network that is not reliant on any central authority, such as a government or bank, to uphold or maintain it. It ...

with the publication of "b-money, an anonymous, distributed electronic cash system". In the paper, Dai outlines the basic properties of all modern day cryptocurrency systems: "...a scheme for a group of untraceable digital pseudonyms to pay each other with money and to enforce contracts amongst themselves without outside help".

Influence on the development of Bitcoin

Described as "money which is impossible to regulate", Dai's '
b-money
'' described the core concepts later implemented in

Bitcoin Bitcoin (abbreviation: BTC; sign: ₿) is a decentralized digital currency that can be transferred on the peer-to-peer bitcoin network. Bitcoin transactions are verified by network nodes through cryptography and recorded in a public distr ...

and other cryptocurrencies: * Requires a specified amount of computational work (aka Proof of work). * The work done is verified by the community who update a collective ledger book. * The worker is awarded funds for their effort. * Exchange of funds is accomplished by collective bookkeeping and authenticated with cryptographic hashes. * Contracts are enforced through the broadcast and signing of transactions with digital signatures (i.e.,

public key cryptography Public-key cryptography, or asymmetric cryptography, is the field of cryptographic systems that use pairs of related keys. Each key pair consists of a public key and a corresponding private key. Key pairs are generated with cryptographic al ...

Relationship with Satoshi Nakamoto

Wei Dai and

Adam Back Adam Back (born July 1970) is a British cryptographer and cypherpunk. He is the CEO of Blockstream, which he co-founded in 2014. He invented Hashcash, which is used in the Bitcoin mining process. Life Back was born in London, England, in Jul ...

were the first two people contacted by Satoshi Nakamoto as he was developing

in 2008 and the b-money paper was referenced in the subsequent Bitcoin whitepaper. In a May 2011 article, noted cryptographer

Nick Szabo Nicholas Szabo is a computer scientist, legal scholar, and cryptographer known for his research in digital contracts and digital currency. He graduated from the University of Washington in 1989 with a degree in computer science and received a J ...

stated:However, Dai questions b-money's influence on Bitcoin: There has been much speculation as to the identity of Satoshi Nakamoto, with suspects including Wei Dai himself,

, and Hal Finney, all of whom have denied the putative identification.

References

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External links

Official WebsiteLessWrong profileEffective Altruism Forum profileSourceForge profileGoogle Scholar profile
{{LessWrong Bitcoin People associated with cryptocurrency People associated with Bitcoin