Wei Dai

Wei Dai (戴维 in Pinyin). is a computer engineer and cypherpunk best known as creator of b-money and the developer of the Crypto++ library. Dai is listed as inventor on U.S. patents 5724279 and 6081598 which were assigned to Microsoft.
== Education and career ==
Mr. Dai graduated from the University of Washington with a degree in computer science and is described as an "intensely private computer engineer". His profile as a member of the advisory board for the (now defunct) VoteHere.net indicated:
"Mr. Dai worked in the Cryptography Research Group at Microsoft Corporation in Redmond, Washington. While at Microsoft, he was involved in the study, design and implementation of cryptosystems for specialized applications. Prior to joining Microsoft, Mr. Dai was a programmer with TerraSciences of Acton, Massachusetts. Mr. Dai holds a Bachelor of Science degree from the University of Washington in computer science, with a minor in mathematics."
== Cryptography ==
Dai has made numerous 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++ ===
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 non-commercial projects, as well as businesses.
=== 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 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 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).
=== Relationship with Satoshi Nakamoto ===
Wei Dai and Adam Back were the first two people contacted by Satoshi Nakamoto as he was developing Bitcoin in 2008 and the b-money paper was referenced in the subsequent Bitcoin whitepaper.
In a May 2011 article, noted cryptographer Nick Szabo states:
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, Nick Szabo, Hal Finney and accompanying denials.
== External links ==
* Home page
* Profile on SourceForge
* Posts on LessWrong
* Profile at the Nakamoto Institute
* Wei Dai - Google Scholar Citations
== References ==