Psiphon

Psiphon
Developer(s)Psiphon, Inc., the Citizen Lab
Initial release2006
Stable release(s)
Windows181 / 12 December 2023; 11 months ago (2023-12-12)
Android393 / 14 March 2024; 8 months ago (2024-03-14)
iOS1.1.25 / 6 March 2024; 8 months ago (2024-03-06)
Repository
Operating systemWindows, Android, iOS
Size
  • Windows: ~5.84 MB
  • Android: ~19.00 MB
TypeInternet censorship circumvention
LicenseGNU General Public License
Websitepsiphon.ca

Psiphon is a free and open-source Internet censorship circumvention tool that uses a combination of secure communication and obfuscation technologies, such as a VPN, SSH, and a Web proxy. Psiphon is a centrally managed and geographically diverse network of thousands of proxy servers, using a performance-oriented, single- and multi-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 assist Internet users to securely bypass the content-filtering systems used by governments to impose censorship of the Internet.

The original concept for Psiphon (1.0) was developed by the Citizen Lab at the University 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 the Citizen Lab at the Munk 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:

  • 3.0 – A cloud-based run-time tunneling system.[5]
  • 2.0 – A cloud-based secure proxy system.[6]
  • 1.0 – The original home-based server software (released by the Citizen Lab in 2004, rewritten and launched in 2006). Psiphon 1.X is no longer supported by Psiphon, Inc. or the Citizen Lab.[7]
  1. ^ Fifield D.; Lan C.; Hynes R.; Wegmann P.; Paxson V. (2015-05-15). "Blocking-resistant communication through domain fronting". Proceedings on Privacy Enhancing Technologies. 2015 (2). Proceedings on Privacy Enhancing Technologies 2015: 46–64. doi:10.1515/popets-2015-0009. S2CID 5626265.
  2. ^ "Archived copy". Archived from the original on 2012-04-12. Retrieved 2012-04-11.{{cite web}}: CS1 maint: archived copy as title (link)
  3. ^ "SafeWeb's Holes Contradict Claims". Wired. 2002-02-12.
  4. ^ Ronald Deibert (2009-05-02). "Psiphon Launch – Let the revolution begin!". Deibert.citizenlab.org. Retrieved 2012-12-12.
  5. ^ "Psiphon-Inc/psiphon: Meta-repo with info about and links to Psiphon resources". GitHub. 2020-05-07. Retrieved 2020-06-24.
  6. ^ "psiphon". Launchpad.net. 13 May 2009. Retrieved 2012-12-12.
  7. ^ "Psiphon – Total Delivery Solution for the Censored Internet". Psiphon.ca. Retrieved 2012-12-12.