Editing GNUnet (section)

{{short description|Framework for decentralized, peer-to-peer networking which is part of the GNU Project}}
{{distinguish|Gnutella}}
{{More citations needed|date=April 2019}}
{{Outdated as of | year = 2019 | month = 04 | day = 18 }}
{{Infobox software
| name = GNUnet
| logo = [[File: Official_logo_of_the_GNUnet_project.svg|250px]]
| screenshot = Gnunet-gtk_0.10_under_arch-gnulinux.png
| caption = GNUnet with the [[GTK+]] user interface
| developer = GNUnet [[Registered association (Germany)|e.V.]]<ref>[https://gnunet.org/en/ev.html GNUnet.org &ndash; About GNUnet e.V.]</ref>
| released = {{Start date and age|2001|11|05}}
| latest release version = {{wikidata|property|preferred|references|edit|Q1007056|P348|P548=Q2804309}}
| latest release date = {{wikidata|qualifier|preferred|single|Q1007056|P348|P548=Q2804309|P577}}
| latest preview version = {{wikidata|property|preferred|references|edit|Q1007056|P348|P548=Q51930650}}
| latest preview date = {{wikidata|qualifier|preferred|single|Q1007056|P348|P548=Q51930650|P577}}
| programming language = [[C (programming language)|C]]<ref>[https://git.gnunet.org/gnunet.git/tree GNUnet Source Code]</ref>
| operating system = official: [[Free software]] operating systems ([[Linux]], [[FreeBSD]], [[NetBSD]], [[OpenBSD]]);<br />unofficial: Other operating systems ([[OS X]], [[Microsoft Windows|Windows]])
| language = Spanish, English, Russian, German, French
| genre = [[Anonymous P2P]], [[Friend-to-friend]]
| license = 2018: [[GNU Affero General Public License|AGPL-3.0-or-later]]{{efn|AGPL-3.0-or-later since 2018-06-05.}}<ref>{{cite web |access-date=June 8, 2018 |url=https://gnunet.org/git/gnunet.git/tree/src/core/core.h?id=4e2504a967ba09643c6dd7e3b9ce400e30adcb3d |title=license notice placed at the top in one of the source files of the project's repository, probably in each of its source files |quote=GNUnet is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.}}</ref><br />2007: [[GNU General Public License|GPL-3.0-or-later]]{{efn|GPL-3.0-or-later from 2007-07-02 until 2018-06-05.}}<br />2001: [[GNU General Public License|GPL-2.0-or-later]]{{efn|GPL-2.0-or-later from 2001 until 2007-07-02.}}
| website = {{URL|https://gnunet.org}}
}}
{{File sharing sidebar}}
[[File:Christian Grothoff - August 2013 - Berlin, Germany.png|thumb|Christian Grothoff, maintainer of GNUnet, in [[Berlin]] on August 1, 2013 at the "[http://youbroketheinternet.org/#august2013 #youbroketheinternet. We'll make ourselves a GNU one.]" event.]]
'''GNUnet''' is a [[software framework]] for [[decentralization|decentralized]], [[peer-to-peer]] [[Computer network|networking]] and an official [[GNU project|GNU]] package. The framework offers [[link encryption]], [[Peering|peer discovery]], [[resource allocation]], communication over many transports (such as [[Transmission Control Protocol|TCP]], [[User Datagram Protocol|UDP]], [[Hypertext Transfer Protocol|HTTP]], [[HTTPS]], [[Wireless LAN|WLAN]] and [[Bluetooth]]) and various basic [[peer-to-peer]] algorithms for [[routing]], [[multicast]] and network size estimation.{{sfn|EvansPolotGrothoff|2012}}<ref>{{Cite thesis|title=The GNUnet System|url=https://hal.inria.fr/tel-01654244|publisher=Université de Rennes 1|date=2017-10-10|degree=habilitation|language=en|first=Christian|last=Grothoff}}</ref>

GNUnet's basic network topology is that of a [[mesh network]]. GNUnet includes a [[distributed hash table]] (DHT) which is a [[randomized]] variant of [[Kademlia]] that can still efficiently route in [[small-world network]]s. GNUnet offers a "[[Friend-to-friend|F2F topology]]" option for restricting connections to only the users' trusted friends. The users' friends' own friends (and so on) can then indirectly exchange files with the users' computer, never using its IP address directly.

GNUnet uses [[Uniform resource identifier]]s (not approved by [[Internet Assigned Numbers Authority|IANA]], although an application has been made).{{when|date=May 2019}} GNUnet URIs consist of two major parts: the module and the module specific identifier. A GNUnet URI is of form <br /><code>gnunet://module/identifier</code> where ''module'' is the module name and ''identifier'' is a module specific string.

The primary codebase is written in [[C (programming language)|C]], but there are [[Language_binding | bindings]] in other languages to produce an API for developing extensions in those languages. GNUnet is part of the [[GNU Project]]. It has gained interest in the [[Hacker culture|hacker community]] after the [[PRISM (surveillance program)|PRISM]] revelations.{{sfn|Grothoff|2013}}

GNUnet consists of several subsystems, of which essential ones are Transport and Core subsystems.{{sfn|FerreiraGrothoffRuth|2003|loc=Figure 1}} Transport subsystem provides insecure link-layer communications, while Core provides peer discovery and encryption.{{sfn|FerreiraGrothoffRuth|2003|loc=II. GNUNET AND THE TRANSPORT LAYER|ps=: "The core is responsible for link-to-link encryption, binding of node identities to routable addresses, and peer discovery."}} On top of the core subsystem various applications are built.

GNUnet includes various P2P applications in the main distribution of the framework, including filesharing, chat and VPN; additionally, a few external projects (such as secushare) are also extending the GNUnet infrastructure.

GNUnet is unrelated to the older [[Gnutella]] P2P protocol. Gnutella is not an official GNU project, while GNUnet is.<ref>{{cite web |title=GNU Software |url=https://www.gnu.org/software/ |website=Software - GNU Project - Free Software Foundation |publisher=Free Software Foundation, Inc. |access-date=25 January 2020}}</ref>