Bram Cohen is an American
computer programmer
A computer programmer, sometimes referred to as a software developer, a software engineer, a programmer or a coder, is a person who creates computer programs — often for larger computer software.
A programmer is someone who writes/creates ...
, best known as the author of the
peer-to-peer
Peer-to-peer (P2P) computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the network. They are said to form a peer-to-peer n ...
(P2P)
BitTorrent protocol in 2001, as well as the first
file sharing
File sharing is the practice of distributing or providing access to digital media, such as computer programs, multimedia (audio, images and video), documents or electronic books. Common methods of storage, transmission and dispersion include r ...
program to use the protocol, also known as
BitTorrent. He is also the co-founder of
CodeCon CodeCon was an annual conference for software hackers and technology enthusiasts, held every year between 2002 and 2009. CodeCon was not intended to be a computer security conference, but a conference with a focus on software developers doing pres ...
and organizer of the
San Francisco Bay Area
The San Francisco Bay Area, often referred to as simply the Bay Area, is a populous region surrounding the San Francisco, San Pablo, and Suisun Bay estuaries in Northern California. The Bay Area is defined by the Association of Bay Area Go ...
P2P-hackers meeting, was the co-author of Codeville and creator of the
Chia cryptocurrency which implements the
proof of space-time
Proof of space (PoS) is a type of consensus algorithm achieved by demonstrating one's legitimate interest in a service (such as sending an email) by allocating a non-trivial amount of memory or disk space to solve a challenge presented by the serv ...
consensus algorithm
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 va ...
.
Early life and career
Cohen grew up in the
Upper West Side
The Upper West Side (UWS) is a neighborhood in the borough of Manhattan in New York City. It is bounded by Central Park on the east, the Hudson River on the west, West 59th Street to the south, and West 110th Street to the north. The Upper West ...
of Manhattan, New York City, as the son of a teacher and computer scientist. He claims he learned the
BASIC programming language
BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of General-purpose programming language, general-purpose, high-level programming languages designed for ease of use. Dartmouth BASIC, The original version was created by John ...
at the age of 5 on his family's
Timex Sinclair
Timex Sinclair was a joint venture established in December 1982 between the British company Sinclair Research and Timex Corporation in an effort to gain an entry into the rapidly growing early-1980s home computer market in North America.
His ...
computer. Cohen passed the
American Invitational Mathematics Examination
The American Invitational Mathematics Examination (AIME) is a highly selective and prestigious 15-question 3-hour test given since 1983 to those who rank in the top 5% on the AMC 12 high school mathematics examination (formerly known as the AHSME) ...
to qualify for the
United States of America Mathematical Olympiad
The United States of America Mathematical Olympiad (USAMO) is a highly selective high school mathematics competition held annually in the United States. Since its debut in 1972, it has served as the final round of the American Mathematics Compe ...
while he attended
Stuyvesant High School
Stuyvesant High School (pronounced ), commonly referred to among its students as Stuy (pronounced ), is a State school, public university-preparatory school, college-preparatory, Specialized high schools in New York City, specialized high school ...
in New York City. He is also an alumnus of the
Hampshire College Summer Studies in Mathematics
Hampshire (, ; abbreviated to Hants) is a ceremonial and non-metropolitan county in western South East England on the coast of the English Channel. Home to two major English cities on its south coast, Southampton and Portsmouth, Hampshire is ...
program. He graduated from Stuyvesant in 1993 and attended
SUNY Buffalo
The State University of New York at Buffalo, commonly called the University at Buffalo (UB) and sometimes called SUNY Buffalo, is a public research university with campuses in Buffalo and Amherst, New York. The university was founded in 1846 ...
. He later dropped out of college to work for several
dot com companies throughout the mid to late 1990s, the last being
MojoNation
Mnet is software to run a peer-to-peer distributed data store for file sharing purpose. It aimed at substituting free sharing of digital resources, typical of P2P networks, with a market regulated by its own currency.
Mnet is a fork of the soft ...
, an ambitious but ill-fated project he worked on with Jim McCoy.
MojoNation allowed people to break up confidential files into encrypted chunks and distribute those pieces on computers also running the software. If someone wanted to download a copy of this encrypted file, they would have to download it simultaneously from many computers. This concept, Cohen thought, was perfect for a
file sharing
File sharing is the practice of distributing or providing access to digital media, such as computer programs, multimedia (audio, images and video), documents or electronic books. Common methods of storage, transmission and dispersion include r ...
program, since programs like
KaZaA take a long time to download a large file because the file is (usually) coming from one source (or "peer"). Cohen designed BitTorrent to be able to download files from many sources, thus
speeding up the download time, especially for users with faster
download
In computer networks, download means to ''receive'' data from a remote system, typically a server such as a web server, an FTP server, an email server, or other similar system. This contrasts with uploading, where data is ''sent to'' a remote s ...
than
upload
Uploading refers to ''transmitting'' data from one computer system to another through means of a network. Common methods of uploading include: uploading via web browsers, FTP clients], and computer terminal, terminals (SCP/ SFTP). Uploading c ...
speeds. Thus, the more popular a file is, the faster a user will be able to download it, since many people will be downloading it at the same time, and these people will also be uploading the data to other users.
Cohen says that he has
Asperger syndrome
Asperger syndrome (AS), also known as Asperger's, is a former neurodevelopmental disorder characterized by significant difficulties in Interpersonal relationship, social interaction and nonverbal communication, along with restricted and re ...
based on a
self diagnosis.
BitTorrent
In April 2001, Cohen quit MojoNation and began work on BitTorrent. Cohen unveiled his ideas at the first
CodeCon CodeCon was an annual conference for software hackers and technology enthusiasts, held every year between 2002 and 2009. CodeCon was not intended to be a computer security conference, but a conference with a focus on software developers doing pres ...
conference, which he and his roommate
Len Sassaman
Leonard Harris Sassaman (April 9, 1980 – July 3, 2011) was an American technologist, information privacy advocate, and the maintainer of the Mixmaster anonymous remailer code and operator of the ''randseed'' remailer. Much of his career gravita ...
created as a showcase event for novel technology projects after becoming disillusioned with the state of technology conferences.
Cohen wrote the first BitTorrent client implementation in
Python
Python may refer to:
Snakes
* Pythonidae, a family of nonvenomous snakes found in Africa, Asia, and Australia
** ''Python'' (genus), a genus of Pythonidae found in Africa and Asia
* Python (mythology), a mythical serpent
Computing
* Python (pro ...
, and
many other programs have since implemented the protocol.
In the summer of 2002, Cohen collected free pornography to lure
beta test
A software release life cycle is the sum of the stages of development and maturity for a piece of computer software ranging from its initial development to its eventual release, and including updated versions of the released version to help impro ...
ers to use the program.
BitTorrent gained its fame for its ability to quickly share large music and movie files online. Cohen has claimed he has never violated copyright law using his software.
Regardless, he is outspoken in his belief that the current media business was doomed to being outmoded despite the
RIAA
The Recording Industry Association of America (RIAA) is a trade organization that represents the music recording industry in the United States. Its members consist of record labels and distributors that the RIAA says "create, manufacture, and/o ...
and
MPAA
The Motion Picture Association (MPA) is an American trade association representing the five major film studios of the United States, as well as the video streaming service Netflix. Founded in 1922 as the Motion Picture Producers and Distribu ...
's legal or technical tactics, such as
digital rights management
Digital rights management (DRM) is the management of legal access to digital content. Various tools or technological protection measures (TPM) such as access control technologies can restrict the use of proprietary hardware and copyrighted works. ...
. In May 2005, Cohen released a
trackerless beta version of BitTorrent.
In late 2003, Cohen had a short career at
Valve
A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fittings ...
working on
Steam
Steam is a substance containing water in the gas phase, and sometimes also an aerosol of liquid water droplets, or air. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization ...
, their
digital distribution
Digital distribution, also referred to as content delivery, online distribution, or electronic software distribution, among others, is the delivery or distribution of digital media content (media), content such as Sound recording and reproductio ...
system introduced for ''
Half-Life 2
''Half-Life 2'' is a 2004 first-person shooter game developed by Valve. It was published by Valve through its distribution service Steam. Like the original ''Half-Life'' (1998), ''Half-Life 2'' combines shooting, puzzles, and storytelling, and ...
''.
By 2004, he had left Valve and formed
BitTorrent, Inc.
Rainberry, Inc., formerly known as BitTorrent, Inc., is an American company that is responsible for the ongoing development of the BitTorrent peer-to-peer protocol, as well as the ongoing development of μTorrent and BitTorrent Mainline, two c ...
with his brother
Ross Cohen and business partner
Ashwin Navin
Ashwin Navin is an Indian-American entrepreneur, who is the CEO and co-founder of Samba TV, a data and analytics service that measures television viewership using opt-in data from Internet-connected devices and set-top boxes. The company has bee ...
. In 2012 he announced a beta-version of BitTorrent Live for TV broadcasting through the Internet.
Cohen left BitTorrent, Inc. in a day to day capacity to co-found
Chia Network
Chia Network Inc. is a US-based blockchain technology company. The company built the Chia blockchain that uses proof of space and proof of time consensus protocols and issues the digital currency Chia (XCH). Chia Network was founded in 2017 by ...
in the fall of 2017.
BitTorrent and the MPAA
By mid-2005, BitTorrent, Inc. was funded by venture capitalist
David Chao from
Doll Capital Management
A doll is a model typically of a human or humanoid character, often used as a toy for children. Dolls have also been used in traditional religious rituals throughout the world. Traditional dolls made of materials such as clay and wood are found ...
, and in late 2005 Cohen and Navin made a deal with the MPAA to remove links to illegal content on the official BitTorrent website. The deal was with the seven largest studios in America. The agreement means the site will comply with procedures outlined in the
Digital Millennium Copyright Act
The Digital Millennium Copyright Act (DMCA) is a 1998 United States copyright law that implements two 1996 treaties of the World Intellectual Property Organization (WIPO). It criminalizes production and dissemination of technology, devices, or s ...
.
Chia Network
Chia Network
Chia Network Inc. is a US-based blockchain technology company. The company built the Chia blockchain that uses proof of space and proof of time consensus protocols and issues the digital currency Chia (XCH). Chia Network was founded in 2017 by ...
is a company founded by Cohen in 2017 that has implemented a
proof of space-time
Proof of space (PoS) is a type of consensus algorithm achieved by demonstrating one's legitimate interest in a service (such as sending an email) by allocating a non-trivial amount of memory or disk space to solve a challenge presented by the serv ...
cryptocurrency
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 i ...
called
Chia. Chia is intended to avoid the waste of energy involved in
proof-of-work
Proof of work (PoW) is a form of cryptographic 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 subsequently confirm this exp ...
based cryptocurrencies such as
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 the vulnerability to state actors of
proof-of-stake
Proof-of-stake (PoS) protocols are a class of consensus mechanisms for blockchain
A blockchain is a type of distributed ledger technology (DLT) that consists of growing lists of records, called ''blocks'', that are securely linked togethe ...
systems.
Chia Network
Chia Network Inc. is a US-based blockchain technology company. The company built the Chia blockchain that uses proof of space and proof of time consensus protocols and issues the digital currency Chia (XCH). Chia Network was founded in 2017 by ...
has raised seed money from investors including
Andreessen Horowitz
Andreessen Horowitz (also called a16z, legal name AH Capital Management, LLC) is a private American venture capital firm, founded in 2009 by Marc Andreessen and Ben Horowitz. The company is headquartered in Menlo Park, California.
Andreessen ...
.
[ The use of storage media (]hard disk
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
and solid-state drives
A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is a ...
) as the cryptocurrency's mining
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic via ...
medium has raised concerns over potential price surges and shortage of high-capacity storage devices, as well as radically shortening the lifetime of drives.
Personal life
As of 2008, Cohen lives in the San Francisco Bay Area
The San Francisco Bay Area, often referred to as simply the Bay Area, is a populous region surrounding the San Francisco, San Pablo, and Suisun Bay estuaries in Northern California. The Bay Area is defined by the Association of Bay Area Go ...
of the United States, with his wife Jenna and their three children.
Cohen's hobbies include original origami
) is the Japanese paper art, art of paper folding. In modern usage, the word "origami" is often used as an inclusive term for all folding practices, regardless of their culture of origin. The goal is to transform a flat square sheet of pape ...
and juggling
Juggling is a physical skill, performed by a juggler, involving the manipulation of objects for recreation, entertainment, art or sport. The most recognizable form of juggling is toss juggling. Juggling can be the manipulation of one object o ...
up to five balls, but his main interest is in recreational mathematics
Recreational mathematics is mathematics carried out for recreation (entertainment) rather than as a strictly research and application-based professional activity or as a part of a student's formal education. Although it is not necessarily limited ...
. Cohen maintains a blog
A blog (a truncation of "weblog") is a discussion or informational website published on the World Wide Web consisting of discrete, often informal diary-style text entries (posts). Posts are typically displayed in reverse chronological order ...
where he frequently discusses trust metric
In psychology and sociology, a trust metric is a measurement or metric of the degree to which one social actor (an individual or a group) trusts another social actor. Trust metrics may be abstracted in a manner that can be implemented on compu ...
s with Raph Levien
Raphael Linus Levien (also known as Raph Levien; born April 6, 1970) is a software developer, a member of the free software developer community, through his creation of the Advogato virtual community and his work with the free software branch of G ...
, as well as money systems, games of skill, and other math-related topics. He is also an assembly puzzle enthusiast. He has designed several puzzles including some in conjunction with Oskar van Deventer
Oskar van Deventer (born 1965) is a Dutch puzzle maker. He prototypes puzzles using 3D printing. His work combines mathematics, physics, and design, and he collaborates at academic institutions. Many of his combination puzzles are in mass produc ...
including several gear-based puzzles such as Gear Shift and a multiple Rubik's Cube
The Rubik's Cube is a Three-dimensional space, 3-D combination puzzle originally invented in 1974 by Hungarians, Hungarian sculptor and professor of architecture Ernő Rubik. Originally called the Magic Cube, the puzzle was licensed by Rubik t ...
variant called Bram's Fortress. Some of Bram's puzzle designs are available for 3-D printing via Shapeways
Shapeways, Inc. is a global, 3D printing marketplace and service, publicly traded company. Users design and upload 3D printable files, and Shapeways prints the objects for them or others. Users can have objects printed in over 55 materials and f ...
.
Awards
Cohen has received a number of awards for his work on the BitTorrent protocol. These awards include:
* 2004 ''Wired
''Wired'' (stylized as ''WIRED'') is a monthly American magazine, published in print and online editions, that focuses on how emerging technologies affect culture, the economy, and politics. Owned by Condé Nast, it is headquartered in San Fra ...
'' Rave Award
* 2005 ''MIT Technology Review
''MIT Technology Review'' is a bimonthly magazine wholly owned by the Massachusetts Institute of Technology, and editorially independent of the university. It was founded in 1899 as ''The Technology Review'', and was re-launched without "The" in ...
'' ''TR''35 as one of the top 35 innovators in the world under the age of 35
* 2005 ''Time'' 100 Most Influential People
* 2006 USENIX STUG Award
* 2010 Internet Evolution 100
References
External links
*
{{DEFAULTSORT:Cohen, Bram
American bloggers
20th-century American Jews
American computer programmers
Cypherpunks
Living people
Stuyvesant High School alumni
University at Buffalo alumni
BitTorrent
Recreational mathematicians
Place of birth missing (living people)
People from San Francisco
People from the Upper West Side
1975 births
21st-century American Jews