| Psiphon | |||||||
|---|---|---|---|---|---|---|---|
 | |||||||
 Psiphon onWindows 10 | |||||||
| Developers | Psiphon, Inc., theCitizen Lab | ||||||
| Initial release | 2006 | ||||||
| Stable release(s) | |||||||
| |||||||
| Operating system | Windows,Android,iOS | ||||||
| Size |
| ||||||
| Type | Internet censorship circumvention | ||||||
| License | GNU General Public License | ||||||
| Website | psiphon | ||||||
| Repository | |||||||
Psiphon is afree and open-sourceInternet censorship circumvention tool that uses a combination of secure communication and obfuscation technologies, such as aVPN,SSH, and aWeb proxy. Psiphon is a centrally managed and geographically diverse network of thousands of proxy servers, using a performance-oriented, single- andmulti-hop routing architecture.[1]
Psiphon is specifically designed to support users in countries considered to be "enemies of the Internet".[2] The codebase is developed and maintained by Psiphon, Inc., which operates systems and technologies designed to assistInternet users to securely bypass the content-filtering systems used by governments to imposecensorship of the Internet.
The original concept for Psiphon (1.0) was developed by theCitizen Lab at theUniversity of Toronto, building upon previous generations of web proxy software systems, such as the "Safe Web"[3] and "Anonymizer" systems.
In 2007 Psiphon, Inc. was established as an independent Ontario corporation that develops advanced censorship circumvention systems and technologies. Psiphon, Inc. and theCitizen Lab at theMunk School of Global Affairs,University of Toronto occasionally collaborate on research projects, through the Psi-Lab partnership.[4]Psiphon currently consists of three separate but related open-source software projects:
The original concept for Psiphon envisioned an easy-to-use and lightweight Internet proxy, designed to be installed and operated by individual computer users, who would then host private connections for friends and family in countries where the Internet is censored. According to Nart Villeneuve, "The idea is to get (users) to install this on their computer, and then deliver the location of that circumventor, to people in filtered countries by the means they know to be the most secure. What we're trying to build is a network of trust among people who know each other, rather than a large tech network that people can just tap into."[8] Psiphon 1.0 was launched by the Citizen Lab on 1 December 2006 as open-source software.[9]
In early 2007, Psiphon, Inc. was established as a Canadian corporation independent of the Citizen Lab and the University of Toronto. The original code (1.6) was made available under theGNU General Public License. In 2008, Psiphon was awarded theNetexplorateur award by theFrench Senate.[10] In 2009, Psiphon was recognized withThe Economist Best New Media Award byIndex on Censorship.[11] In 2011, Psiphon 1.X was officially retired and is no longer actively supported by Psiphon, Inc., or the Citizen Lab.[7]
In 2008, Psiphon, Inc. was awarded two sub-grants by the Internews operated SESAWE (Open Internet) project(s).[9][12] The source of funding came from the European Parliament and theUS State DepartmentInternet Freedom program, administered by theBureau of Democracy, Human Rights, and Labor (DRL).[13] The objective of these grants was to develop Psiphon into a scalable anti-censorship solution capable of supporting large numbers of users across different geographic regions. The core development team grew to include a group of experienced security and encryption software engineers that previously developedCiphershare, a securedocument management system.[14]
In 2010, Psiphon, Inc. began providing services to theBroadcasting Board of Governors (US),US Department of State and theBritish Broadcasting Corporation. As of 2015[update], Psiphon, Inc. operated on the basis revenues generated from commercial operations.
Communication via Psiphon played a major role in media coverage of the2020 Belarusian protests.
In 2012, Psiphon, Inc. began development of a mobile version of Psiphon 3 for use with phones runningAndroid.[15]
In April 2024, theOpen Technology Fund (OTF) announced increased long-term funding for several Internet circumvention tools, including Psiphon, to help sustain access for millions of monthly users in China, Iran, and Russia.[16] Subsequent OTF awards to Psiphon totaled US$18.54 million for 2024 and US$5.87 million for 2025.[17]
In 2021, the monthly user base surged from 5,000 to over 14 million due to the Myanmar protests. It is thought that the state censorship of many other social media websites is the cause.
During the2021 Cuban protests, over one million protesters began using the tool after the government shut down many social media websites.[18]
DuringAzerbaijan's September 2022 invasion of Armenia, both countries' governments implemented internet-blocks, resulting in a surge in Psiphon use.[19]
In the aftermath of the2026 Iranian protests that country became the world's largest user of Psiphon, withTor's Snowflake feature,Lantern's unbounded mode, andWireGuard-based tools seeing more intermittent success.[20]
{{cite web}}: CS1 maint: archived copy as title (link){{cite web}}: CS1 maint: numeric names: authors list (link)Internet censorship circumvention technologies | |||||||
|---|---|---|---|---|---|---|---|
| Background |
| ||||||
| Principles |
| ||||||
| Anti-censorship software |
| ||||||
| Anonymity |
| ||||||
| Physical circumvention methods | |||||||
| Relevant organizations | |||||||
| Reference | |||||||
