Bram Cohen

Cofounder of BitTorrent

• Born: October 12, 1975
• Place of Birth: New York, New York

Primary Company/Organization: BitTorrent

Introduction

The father of BitTorrent, Bram Cohen developed a peer-to-peer file-sharing protocol (and wrote its first client program in Python), which has since taken up nearly half of the Internet's traffic. What BitTorrent offered was not a single service or site, such as Napster and previous peer-to-peer file-sharing programs, but a protocol to be used by programs to distribute “torrents” of data, bit by bit. Cohen founded BitTorrent, Inc., to continue to support the program, which has become the most successful peer-to-peer file-sharing program. He was recognized in 2005 as an influential business leader, named to Technology Review's TR35 (thirty-five innovators under age thirty-five) and Time magazine's 100 Most Influential People.

Early Life

Bram Cohen was born on October 12, 1975, in New York City. The son of a computer scientist and a teacher, he grew up on the upper West Side and attended Stuyvesant High School. A mathematics prodigy who competed in the USA Mathematical Olympiad, he became interested in computer programming early, beginning on the household's Timex Sinclair computer, an early personal computer.

Cohen attended the State University of New York at Buffalo but dropped out during the dot-com boom to work for several start-ups in succession, the most significant of which was Evil Geniuses for a Better Tomorrow. Jim McCoy had founded that company to develop Mojo Nation, a digital cash system that used encrypted data. The venture reflected its place in geek culture: The company's name was taken from Steve Jackson Games' Illuminati card game (which was inspired in part by Robert Anton Wilson's Illuminatus! books of counterculture conspiracy theory fiction), while Mojo Nation reflected the influence of Hakim Bey, who had written about eighteenth-century pirate culture and “temporary autonomous zones.” Bey's writing had barely preceded the 1990s rise of the Internet, and the counterculture embraced the idea of the Internet as a virtual space where these autonomous zones, rather than the communes and new sovereignties that Bey had envisioned, could be created. Although Mojo Nation was funded by venture capital, its intent was to create an open source marketplace, one protected by encryption, in which virtual cash (mojo) was used to buy and sell services.

Mojo Nation was developed and launched during the heyday of Napster and the popularity of decentralized peer-to-peer file sharing, and it used similar principles. The space required by Mojo Nation to operate was scattered across users' computers; in return for renting part of their computing resources (memory, processing, and so on) in order to keep the network running, each user received a payment in mojo. That mojo could then be exchanged with other users in return for whatever was on offer. The essential engine of the Mojo Nation economy was in broad strokes the same as that which drives real-world economies: A central authority creates and distributes money, the value of which fluctuates in response to its supply and the economic activity to which it is put to use. McCoy had a utopian vision according to which the system would encourage people to share and to pay the artists and other copyright holders who had created the works being distributed through the system; he thought it would change the Internet entirely and would be protected from obsolescence in a way Napster and its cohorts (such as Gnutella and Kazaa) were not. What particularly interested Cohen, though, was the way Mojo Nation handled file transfers: breaking up large files into small, encrypted pieces in order to limit the bandwidth of its transfers and minimize the system's impact on any given user's computer. This method of file transfer was key to the system's scalability.

Cohen left Mojo Nation in 2001, inspired to create a new project: BitTorrent. He spent nine months writing it, during what he has called his “starving artist period.”

Life's Work

Cohen announced BitTorrent, a new file-sharing program, at the first CodeCon conference, organized by Cohen and his roommate, privacy advocate and Anonymizer systems engineer Len Sassaman. The first CodeCon was held in 2002 at San Francisco's DNA Lounge; it continued to be held every year until 2009, focusing on developers presenting technologies in development.

It took a few years to refine the BitTorrent protocol, and after the CodeCon presentation, Cohen distributed free pornography with the protocol to encourage beta testers to sign up. Cohen briefly worked for Valve Software—developing the digital distribution system Steam—in 2003, but in 2004 he started BitTorrent, Inc., with Ross Cohen (his brother) and Ashwin Navin.

BitTorrent was designed as a peer-to-peer file-sharing protocol to distribute data over Internet connections. Numerous client programs have been developed to use BitTorrent; Cohen wrote both the protocol and the first client program (also called BitTorrent). While previous peer-to-peer programs exchange a file from one peer to another, BitTorrent was designed to handle downloads from multiple sources of the same file—even from other users who are in the process of downloading it and do not yet have a complete copy. (Users sharing complete copies are called “seeds”; continuing to provide access to a downloaded file is “seeding.”) Provided users continued to seed anything they downloaded, the most popular files (the files in greatest demand) would also be the fastest to download, since they would have the greatest number of available copies and the most users sharing them.

While various torrent servers offer copyright-infringing material—which has led to some notorious site shutdowns and arrests, including those of The Pirate Bay and Demonoid—the official BitTorrent website has an agreement with the Motion Picture Association of America (MPAA) dating from 2005, according to which no illegal material will be listed and the site will adhere to the procedures of the Digital Millennium Copyright Act. Despite this cooperation with Hollywood, Cohen has been straightforward in his dissatisfaction with the conventional media distribution model and his hope to “kill off television” (that is, the traditional broadcast model), already threatened legitimately by time-deferred viewing like that offered by Hulu, Netflix, DVDs, DVRs, and on-demand cable services, and illegitimately by copyright-infringing file sharing. The successor to BitTorrent, in Cohen's view, will be a similar peer-to-peer distribution system (which some have called “peercasting”) that supplants over-the-air and cable broadcasting.

Cohen left BitTorrent Inc. in 2018 after it was acquired by the cryptocurrency startup TRON. Though he distanced himself from BitTorrent's new owners, Cohen became interested in starting a new cryptocurrency himself, dubbed Chia. In 2019, he became the CEO of the resulting company he helped found, Chia Network.

Cohen also did some of the design work on his brother Ross's Codeville, a Python-written distributed revision control system. Revision control systems manage changes to bodies of data, such as programs, websites, and documents.

Personal Life

Cohen and his wife, Jenna, have three children. He continues to be interested in mathematics and regularly delves into recreational mathematics and related topics on his blog, as well as discussing programming issues and engineering problems. His hobbies include origami, juggling, and puzzles.

Cohen is self-diagnosed with Asperger syndrome, an autism spectrum disorder. He has expressed the belief that his condition contributed to social difficulties in his adolescence, which in turn encouraged his computer programming by focusing his attention away from the social sphere. He is sometimes uncomfortable in everyday social situations and admits to a tendency to lecture at length, without concern for his audience's interest level or ability to follow his train of thought. The disorder also led to difficulties in his early work life, when he would undiplomatically criticize the business plan or other elements of his employers. Asperger syndrome is somewhat more common in Silicon Valley than elsewhere, however, and the disorder has not proven an obstacle in his career.

Bibliography

Aigrain, Philippe. Sharing: Culture and Economy in the Internet Age. Amsterdam: Amsterdam UP, 2012. Print.

Botsman, Rachel, and Roo Rogers. What's Mine Is Yours: The Rose of Collaborative Consumption. New York: HarperCollins, 2012. Print.

Dale, Brady. "BitTorrent Creator Bram Cohen Takes Over as CEO at Chia Network." CoinDesk, 17 June 2019, www.coindesk.com/bittorrent-creator-bram-cohen-takes-over-as-ceo-at-chia-network. Accessed 28 Oct. 2019.

Gold, Lorna. The Sharing Economy: Solidarity Networks Transforming Globalization. Burlington: Ashgate, 2004. Print.

Levine, Adam B., and Leigh Cuen. "Bram Cohen: 'Getting Rich Is a Terrible Metric of Success.'" CoinDesk, 14 Sept. 2021, www.coindesk.com/markets/2020/04/19/bram-cohen-getting-rich-is-a-terrible-metric-of-success/. Accessed 5 Mar. 2024.

Roth, Daniel. “Torrential Reign.” Fortune 31 Oct. 2005: n. pag. Print.

Thompson, Clive. “The BitTorrent Effect.” Wired 13.1 (2005): n. pag. Print.