Wei Dai ( zh, c=戴伟) is a

computer engineer Computer engineering (CoE or CpE) is a branch of electrical engineering and computer science that integrates several fields of computer science and electronic engineering required to develop computer hardware and software. Computer engineers ...

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 VMAC is a block cipher-based message authentication code (MAC) algorithm using a universal hash proposed by Ted Krovetz and Wei Dai Wei Dai ( zh, c=戴伟) is a computer engineer known for contributions to cryptography and cryptocurrencies. ...

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 be c ...

, 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 Seattle a ...

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 Eliezer Shlomo Yudkowsky (born September 11, 1979) is an American decision theory and artificial intelligence (AI) researcher and writer, best known for popularizing the idea of friendly artificial intelligence. He is a co-founder and research ...

Robin Hanson Robin Dale Hanson (born August 28, 1959) is an associate professor of economics at George Mason University and a research associate at the Future of Humanity Institute of Oxford University. He is known for his work on idea futures and markets, ...

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 rev ...

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 th ...

Eric Drexler Kim Eric Drexler (born April 25, 1955) is an American engineer best known for studies of the potential of molecular nanotechnology (MNT), from the 1970s and 1980s. His 1991 doctoral thesis at Massachusetts Institute of Technology was revised and ...

, 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 In cryptography, a block cipher mode of operation is an algorithm that uses a block cipher to provide information security such as confidentiality or authenticity. A block cipher by itself is only suitable for the secure cryptographic transforma ...

(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

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 A bank is a financial i ...

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 Proof of work (PoW) is a form of Cryptography, cryptographic proof (truth), proof in which one party (the ''prover'') proves to others (the ''verifiers'') that a certain amount of a specific computational effort has been expended. Verifiers can s ...

). * 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 alg ...

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 July ...

were the first two people contacted by

Satoshi Nakamoto Satoshi Nakamoto is the name used by the presumed pseudonymous person or persons who developed bitcoin, authored the bitcoin white paper, and created and deployed bitcoin's original reference implementation. As part of the implementation, Nakam ...

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

References

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External links

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