Wei Dai (Chinese: 戴维[1]orChinese: 戴伟[2]) is a computer engineer known for contributions to cryptography and cryptocurrencies. He developed the Crypto++ cryptographic library, created the b-money cryptocurrency system, and co-proposed the VMAC message authentication algorithm.
Crypto++ is an open-source C++library that provides implementations of cryptographic algorithms. It was originally written by Dai and first released in 1995.[9][10] In June 2015 Dai stepped away from the Crypto++ project to work on other projects, with the Crypto++ community continuing to maintaining the project.[11]
In 1998, Dai helped to spark interest in cryptocurrencies[12] with the publication of "b-money, an anonymous, distributed electronic cash system".[13][14] 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".[15][16]
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.[17][18]
Described as "money which is impossible to regulate",[19] Dai's b-money described the core concepts later implemented in Bitcoin[20] 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).
Wei Dai and Adam Back were the first two people contacted by Satoshi Nakamoto as he was developing Bitcoin in 2008[4] and the b-money paper was referenced in the subsequent Bitcoin whitepaper.[21]
In a May 2011 article, noted cryptographer Nick Szabo stated:
Myself, Wei Dai, and Hal Finney were the only people I know of who liked the idea (or in Dai's case his related idea) enough to pursue it to any significant extent until Nakamoto (assuming Nakamoto is not really Finney or Dai).[22]
However, Dai questions b-money's influence on Bitcoin:
...my understanding is that the creator of Bitcoin, who goes by the name Satoshi Nakamoto, didn't even read my article before reinventing the idea himself. He learned about it afterward and credited me in his paper. So my connection with the project is quite limited.[23]
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.[24][25][12][26]
^Chivers, Tom (2019). The AI Does Not Hate You: Superintelligence, Rationality and the Race to Save the World. United Kingdom: Weidenfeld & Nicolson. ISBN978-1-4746-0877-0.
^ZiJie, Xu. "Some Fixes To SSH"(PDF). International Association for Cryptologic Research. Retrieved 16 September 2015.
This article incorporates text byTaras and JonathanCross available under the CC BY-SA 3.0 license.
