View source for I2P

{{Short description|Free and open source project building an anonymous network}}
{{Primary sources|article|date=August 2017}}

{{Infobox software
| title =
| name = I2P&nbsp;— The Anonymous Network
| logo = [[file:I2P logo.svg]]
| logo_size = 300px
| logo_alt =
| logo caption =
| screenshot = <!--  Image name is enough -->
| screenshot_size =
| screenshot_alt =
| caption = I2P 0.9.8.1 Router Console
| collapsible =
| author = I2P Team<ref name="team">{{cite web |url=https://geti2p.net/en/about/team |title=I2P Project Members |website=geti2p.net |access-date=22 November 2015 |archive-date=26 February 2019 |archive-url=https://web.archive.org/web/20190226201821/http://geti2p.net/en/about/team |url-status=live }}</ref>
| developer =
| released = {{Start date and age|2003}}
| latest release version = {{wikidata|property|preferred|references|edit|Q565283|P348|P548=Q2804309}}
| latest release date = {{Start date and age|{{wikidata|qualifier|preferred|single|Q565283|P348|P548=Q2804309|P577}}}}
| latest preview version = {{wikidata|property|preferred|references|edit|Q565283|P348|P548=Q51930650}}
| latest preview date = {{Start date and age|{{wikidata|qualifier|preferred|single|Q565283|P348|P548=Q51930650|P577}}}}
| programming language = [[Java (programming language)|Java]]
| operating system = [[Cross-platform]]: [[Unix-like]] ([[Android operating system|Android]], [[Linux]], [[BSD]], [[macOS]]), [[Microsoft Windows]]
| platform =
| size =
| language = English, Spanish<br />Incomplete translations: Russian, French, Romanian, German, Swedish, Italian, Portuguese, Chinese, Dutch, Polish, Hungarian, Arabic, Japanese, Estonian, Persian<ref>{{Citation | title = I2P | url = https://www.transifex.com/projects/p/I2P/ | publisher = Transifex | type = project | access-date = 2014-02-12 | archive-date = 2013-12-25 | archive-url = https://web.archive.org/web/20131225141917/https://www.transifex.com/projects/p/I2P/ | url-status = live }}.</ref>
| language count = <!-- DO NOT include this parameter unless you know what it does -->
| language footnote =
| genre = [[Anonymity application]], [[Overlay network]], [[mix network]], [[garlic routing|garlic router]], [[peer-to-peer]]
| license = [[Public domain]], [[BSD licenses|BSD]], [[GNU General Public License|GPL]], [[MIT License|MIT]] (license varies by component)<ref>{{
Citation
| access-date = 2013-12-24
| archive-date = 2013-12-24
| archive-url = https://web.archive.org/web/20131224112728/https://geti2p.net/en/get-involved/develop/licenses
| contribution = Licenses
| contribution-url = https://geti2p.net/en/get-involved/develop/licenses
| publisher = Get I2P
| title = Get involved
| url-status = live
}}</ref>
| alexa =
| website = {{URL|https://geti2p.net/}}
| standard =
| AsOf =
}}
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The '''Invisible Internet Project''' ('''I2P''') is an anonymous network layer (implemented as a [[mix network]]) that allows for [[Internet censorship circumvention|censorship-resistant]], [[peer-to-peer]] communication.  Anonymous connections are achieved by [[Encryption|encrypting]] the user's traffic (by using [[end-to-end encryption]]), and sending it through a volunteer-run network of roughly 55,000 computers distributed around the world. Given the high number of possible paths the traffic can transit, a third party watching a full connection is unlikely. The software that implements this layer is called an "I2P router", and a computer running I2P is called an "I2P node". I2P is [[Free software|free]] and [[Open-source software|open source]], and is published under multiple [[software license|licenses]].<ref>{{Cite web|url=https://arstechnica.com/information-technology/2015/01/under-the-hood-of-i2p-the-tor-alternative-that-reloaded-silk-road/|title=Under the hood of I2P, the Tor alternative that reloaded Silk Road|last=Gallagher|first=Sean|date=2015-01-13|website=[[Ars Technica]]|language=en-us|archive-url=https://archive.today/20190712191700/https://arstechnica.com/information-technology/2015/01/under-the-hood-of-i2p-the-tor-alternative-that-reloaded-silk-road/|archive-date=2019-07-12|url-status=live|access-date=2019-08-17}}</ref>

== Technical design ==
I2P started in 2003 as a fork of [[Freenet]].<ref name="urlAnonymity Networks: VPNs, Tor, and I2P | Restore Privacy">{{cite web |url=https://restoreprivacy.com/anonymity-networks/ |title=Anonymity Networks: VPNs, Tor, and I2P &#124; Restore Privacy |date=3 February 2020 |format= |accessdate= |archive-date=28 January 2021 |archive-url=https://web.archive.org/web/20210128084403/https://restoreprivacy.com/anonymity-networks/ |url-status=live }}</ref><ref>{{Citation | url = https://geti2p.net/en/blog/ | type = blog | title = Get I2P | access-date = 2013-12-24 | archive-date = 2017-07-02 | archive-url = https://web.archive.org/web/20170702010806/https://geti2p.net/en/blog/ | url-status = live }}.</ref>

The network is strictly message-based, like [[Internet Protocol|IP]], but a [[Library (computing)|library]] is available to allow reliable [[Streaming algorithm|streaming]] communication on top of it (similar to [[Non-blocking IO]]-based [[Transmission control protocol|TCP]], although from version 0.6, a new ''Secure Semi-reliable'' [[User Datagram Protocol|UDP]] transport is used<ref>{{cite web |title=Secure Semireliable UDP (SSU) |url=https://geti2p.net/en/docs/transport/ssu |access-date=18 May 2023 |archive-url=https://archive.today/20230906220752/https://geti2p.net/en/docs/transport/ssu |archive-date=6 September 2023 |website=geti2p.net}}</ref>). All communication is [[end-to-end encrypted]] (in total, four layers of encryption are used when sending a message) through [[garlic routing]],<ref>{{cite web|url=https://geti2p.net/en/docs/how/garlic-routing|title=Garlic Routing – I2P|website=geti2p.net|access-date=2017-12-12|archive-date=2019-11-16|archive-url=https://web.archive.org/web/20191116095738/https://geti2p.net/en/docs/how/garlic-routing|url-status=live}}</ref> and even the [[Communication endpoint|end points]] ("destinations") are [[cryptographic]] identifiers (essentially a pair of [[public key]]s), so that neither senders nor recipients of messages need to reveal their [[IP address]] to the other side or to third-party observers.

Although many developers had been a part of the Invisible IRC Project (IIP)<ref>{{Citation | title = Invisible IP | publisher = Source forge | contribution = IIP | contribution-url = http://invisibleip.sourceforge.net/iip/ | access-date = 2012-02-11 | archive-date = 2009-05-18 | archive-url = https://web.archive.org/web/20090518155407/http://invisibleip.sourceforge.net/iip/ | url-status = live }}.</ref> and [[Freenet]] communities,  significant differences exist between their designs and concepts. IIP was an anonymous centralized [[Internet Relay Chat|IRC]] server.  Freenet is a [[censorship]]-resistant [[distributed data store]]. I2P is an [[Anonymous P2P|anonymous peer-to-peer]] distributed communication layer designed to run ''any'' traditional internet service (e.g. [[Usenet]], [[email]], [[Internet Relay Chat|IRC]], [[file sharing]], [[Web hosting]] and [[HTTP]], or [[Telnet]]), as well as more traditional distributed applications (e.g. a distributed data store, a [[web proxy]] network using [[Squid (software)|Squid]], or [[Domain Name System|DNS]]).

Many developers of I2P are known only under [[Pseudonymity|pseudonyms]].  While the previous main developer, ''[[J. Random Hacker|jrandom]]'', is currently on hiatus,<ref>{{Cite web|url=https://geti2p.net/en/misc/jrandom-awol|title=Jrandom's Announcement – I2P|website=geti2p.net|language=en|access-date=2017-07-15|archive-date=2017-08-19|archive-url=https://web.archive.org/web/20170819182716/https://geti2p.net/en/misc/jrandom-awol|url-status=live}}</ref> others, such as ''zzz'', ''killyourtv'', and ''Complication'' have continued to lead development efforts,{{source?|date=September 2023}} and are assisted by numerous contributors.<ref name="team"/>

I2P uses 2048bit [[ElGamal]]/[[AES256]]/[[SHA256]]+Session Tags encryption<ref>{{cite web|url=https://geti2p.net/pl/docs/how/elgamal-aes|title=ElGamal/AES + SessionTag Encryption – I2P|website=geti2p.net|access-date=2017-03-30|archive-date=2017-03-31|archive-url=https://web.archive.org/web/20170331115147/https://geti2p.net/pl/docs/how/elgamal-aes|url-status=live}}</ref> and [[Ed25519]] [[EdDSA]]/[[ECDSA]] [[Digital signature|signatures]].<ref>{{cite web|url=https://trac.i2p2.de/wiki/Crypto/ECDSA|title=Crypto/ECDSA – I2P Bugtracker|website=trac.i2p2.de|access-date=2017-03-30|archive-date=2015-05-20|archive-url=https://web.archive.org/web/20150520144801/https://trac.i2p2.de/wiki/Crypto/ECDSA|url-status=live}}</ref>

=== Releases ===
I2P has had a stable release every six to eight weeks.  Updates are distributed via I2P torrents and are signed by the release manager (generally ''str4d'' or ''zzz''{{efn|stepped back after the 2.1.0 release}}).
{|class="wikitable collapsible collapsed" style="border:none"
|-
!scope="col"|I2P Versions
|-
|style="padding:0;border:none"|
{| class="wikitable sortable" style="margin-bottom:0;margin:0;width:100%;"
|-
! Version
!data-sort-type="isoDate" | Release date
! Release notes
<!-- If someone wants to do even older releases please do :) -->
|-
! {{Version |o |0.9.11}}
| style="text-align:right;"| 2014-02-08
| style="border-left:0;"| Support for outproxy plugins, improves lease set lookup security, and reduces memory usage.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2014/02/08/0.9.11-Release |title=0.9.11 Release |website=geti2p.net |author=zzz |date=8 February 2014 |access-date=15 September 2015 |archive-date=2 September 2016 |archive-url=https://web.archive.org/web/20160902053526/https://geti2p.net/en/blog/post/2014/02/08/0.9.11-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.12}}
| style="text-align:right;"| 2014-03-31
| style="border-left:0;"| Support for [[Elliptic Curve Digital Signature Algorithm|ECDSA]] and updates to [[Jetty (web server)|Jetty 8]].<ref>{{cite web |url=https://geti2p.net/en/blog/post/2014/03/31/0.9.12-Release |title=0.9.12 Release |website=geti2p.net |author=zzz |date=31 March 2014 |access-date=15 September 2015 |archive-date=2 September 2016 |archive-url=https://web.archive.org/web/20160902053637/https://geti2p.net/en/blog/post/2014/03/31/0.9.12-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.13}}
| style="text-align:right;"| 2014-05-22
| style="border-left:0;"| [[SusiMail]] improvements and fixes for firewalled router.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2014/05/22/0.9.13-Release |title=0.9.13 Release |website=geti2p.net |author=zzz |date=22 May 2014 |access-date=15 September 2015 |archive-date=2 August 2015 |archive-url=https://web.archive.org/web/20150802004440/https://geti2p.net/en/blog/post/2014/05/22/0.9.13-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.14}}
| style="text-align:right;"| 2014-07-26
| style="border-left:0;"| Critical fixes for [[Cross-site scripting|XSS]] and remote execution vulnerabilities.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2014/07/26/0.9.14-Release |title=0.9.14 Release |website=geti2p.net |author=zzz |date=26 July 2014 |access-date=15 September 2015 |archive-date=6 October 2015 |archive-url=https://web.archive.org/web/20151006153114/https://geti2p.net/en/blog/post/2014/07/26/0.9.14-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.14.1}}
| style="text-align:right;"| 2014-08-09
| style="border-left:0;"| I2PSnark and console fixes.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2014/08/09/0.9.14.1-Release |title=0.9.14.1 Release |website=geti2p.net |author=zzz |date=9 August 2014 |access-date=15 September 2015 |archive-date=2 September 2016 |archive-url=https://web.archive.org/web/20160902053707/https://geti2p.net/en/blog/post/2014/08/09/0.9.14.1-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.15}}
| style="text-align:right;"| 2014-09-20
| style="border-left:0;"| Preliminary support for Ed25519 [[EdDSA]] signatures.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2014/09/20/0.9.15-Release |title=0.9.15 Release |website=geti2p.net |author=zzz |date=20 September 2014 |access-date=15 September 2015 |archive-date=28 June 2017 |archive-url=https://web.archive.org/web/20170628175118/https://geti2p.net/en/blog/post/2014/09/20/0.9.15-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.16}}
| style="text-align:right;"| 2014-11-01
| style="border-left:0;"| Add support for stronger Router Info signatures.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2014/11/01/0.9.16-Release |title=0.9.16 Release |website=geti2p.net |author=zzz |date=1 November 2014 |access-date=15 September 2015 |archive-date=3 March 2016 |archive-url=https://web.archive.org/web/20160303221710/https://geti2p.net/en/blog/post/2014/11/01/0.9.16-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.17}}
| style="text-align:right;"| 2014-11-30
| style="border-left:0;"| Signed news, ECDSA tunnels by default.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2014/11/30/0.9.17-Release |title=0.9.17 Release |website=geti2p.net |author=zzz |date=30 November 2014 |access-date=15 September 2015 |archive-date=17 December 2015 |archive-url=https://web.archive.org/web/20151217140055/https://geti2p.net/en/blog/post/2014/11/30/0.9.17-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.18}}
| style="text-align:right;"| 2015-02-22
| style="border-left:0;"| Shortened the startup time, and reduced latency throughout our network protocols.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2015/02/22/0.9.18-Release |title=0.9.18 Release |website=geti2p.net |author=zzz |date=22 February 2015 |access-date=15 September 2015 |archive-date=11 September 2015 |archive-url=https://web.archive.org/web/20150911231358/https://geti2p.net/en/blog/post/2015/02/22/0.9.18-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.19}}
| style="text-align:right;"| 2015-04-12
| style="border-left:0;"| Several fixes and improvements for floodfill performance.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2015/04/12/0.9.19-Release |title=0.9.19 Release |website=geti2p.net |author=zzz |date=12 April 2015 |access-date=4 May 2015 |archive-date=19 April 2015 |archive-url=https://web.archive.org/web/20150419014818/https://geti2p.net/en/blog/post/2015/04/12/0.9.19-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.20}}
| style="text-align:right;"| 2015-06-02
| style="border-left:0;"| Important bug fixes, and several changes to increase floodfill capacity in the network.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2015/06/02/0.9.20-Release |title=0.9.20 Release |website=geti2p.net |author=zzz |date=2 June 2015 |access-date=15 September 2015 |archive-date=11 September 2015 |archive-url=https://web.archive.org/web/20150911230120/https://geti2p.net/en/blog/post/2015/06/02/0.9.20-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.21}}
| style="text-align:right;"| 2015-07-31
| style="border-left:0;"| Contains several changes to add capacity to the network, increase the efficiency of the floodfills, and use bandwidth more effectively.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2015/07/31/0.9.21-Release |title=0.9.21 Release |website=geti2p.net |author=zzz |date=31 July 2015 |access-date=2 August 2015 |archive-date=11 September 2015 |archive-url=https://web.archive.org/web/20150911224558/https://geti2p.net/en/blog/post/2015/07/31/0.9.21-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.22}}
| style="text-align:right;"| 2015-09-12
| style="border-left:0;"| Fixes for I2PSnark getting stuck before completion, and begins the migration of router infos to new, stronger Ed25519 signatures.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2015/09/12/0.9.22-Release |title=0.9.22 Release |website=geti2p.net |author=zzz |date=12 December 2015 |access-date=13 September 2015 |archive-date=4 March 2016 |archive-url=https://web.archive.org/web/20160304023818/https://geti2p.net/en/blog/post/2015/09/12/0.9.22-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.23}}
| style="text-align:right;"| 2015-11-19
| style="border-left:0;"| Accelerates the rekeying process.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2015/11/19/0.9.23-Release |title=0.9.23 Release |website=geti2p.net |author=str4d |date=19 November 2015 |access-date=20 November 2015 |archive-date=21 November 2015 |archive-url=https://web.archive.org/web/20151121022830/https://geti2p.net/en/blog/post/2015/11/19/0.9.23-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.24}}
| style="text-align:right;"| 2016-01-27
| style="border-left:0;"| A new version of SAM (v3.2) and numerous bug fixes and efficiency improvements. The first release to require Java 7.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2016/01/27/0.9.24-Release |title=0.9.24 Release |website=geti2p.net |author=zzz |date=27 January 2016 |access-date=29 January 2016 |archive-date=2 February 2016 |archive-url=https://web.archive.org/web/20160202172218/https://geti2p.net/en/blog/post/2016/01/27/0.9.24-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.25}}
| style="text-align:right;"| 2016-03-22
| style="border-left:0;"| A new version of SAM (v3.3), QR codes for sharing hidden services, identicons and router families.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2016/03/22/0.9.25-Release |title=0.9.25 Release |website=geti2p.net |author=zzz |date=3 March 2016 |access-date=23 March 2016 |archive-date=3 April 2016 |archive-url=https://web.archive.org/web/20160403120511/https://geti2p.net/en/blog/post/2016/03/22/0.9.25-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.26}}
| style="text-align:right;"| 2016-06-07
| style="border-left:0;"| Major upgrade to the native crypto library, a new addressbook subscription protocol with signatures, and major improvements to the Debian/Ubuntu packaging.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2016/06/07/0.9.26-Release |title=0.9.26 Release |website=geti2p.net |author=zzz |date=7 June 2016 |access-date=7 June 2016 |archive-date=2 September 2016 |archive-url=https://web.archive.org/web/20160902053532/https://geti2p.net/en/blog/post/2016/06/07/0.9.26-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.27}}
| style="text-align:right;"| 2016-10-17
| style="border-left:0;"| Improvements in IPv6 transports, SSU peer testing, and hidden mode.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2016/10/17/0.9.27-Release |title=0.9.27 Release |website=geti2p.net |author=zzz |date=17 October 2016 |access-date=6 January 2017 |archive-date=6 February 2017 |archive-url=https://web.archive.org/web/20170206173237/https://geti2p.net/en/blog/post/2016/10/17/0.9.27-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.28}}
| style="text-align:right;"| 2016-12-12
| style="border-left:0;"| Updates for a number of bundled software, fixes for IPv6 peer testing, improvements to detect and block potentially malicious peers. Preliminary fixes for Java 9.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2016/12/12/0.9.28-Release |title=0.9.28 Release |website=geti2p.net |author=zzz |date=12 December 2016 |access-date=15 July 2017 |archive-date=29 August 2017 |archive-url=https://web.archive.org/web/20170829040223/https://geti2p.net/en/blog/post/2016/12/12/0.9.28-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.29}}
| style="text-align:right;"| 2017-02-27
| style="border-left:0;"| Support for NTP over IPv6, preliminary Docker support, translated main pages. We now pass same-origin Referrer headers through the HTTP proxy. There are more fixes for Java 9, although we do not yet recommend Java 9 for general use.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2017/02/27/0.9.29-Release |title=0.9.29 Release |website=geti2p.net |author=zzz |date=27 February 2017 |access-date=5 March 2017 |archive-date=6 March 2017 |archive-url=https://web.archive.org/web/20170306034203/https://geti2p.net/en/blog/post/2017/02/27/0.9.29-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.30}}
| style="text-align:right;"| 2017-05-03
| style="border-left:0;"| Support for Debian Stretch and Ubuntu Zesty, upgraded to Jetty 9 and Tomcat 8, support for the migration of old DSA-SHA1 hidden services to the EdDSA signature type.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2017/05/03/0.9.30-Release |title=0.9.30 Release |website=geti2p.net |author=zzz |date=3 May 2017 |access-date=14 June 2017 |archive-date=3 October 2020 |archive-url=https://web.archive.org/web/20201003145000/https://geti2p.net/en/blog/post/2017/05/03/0.9.30-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.31}}
| style="text-align:right;"| 2017-08-07
| style="border-left:0;"| Refreshed the router console to improve readability, improved accessibility and cross-browser support, and general tidying up.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2017/08/07/0.9.31-Release |title=0.9.31 Release |website=geti2p.net |author=zzz |date=7 August 2017 |access-date=11 August 2017 |archive-date=11 August 2017 |archive-url=https://web.archive.org/web/20170811060150/https://geti2p.net/en/blog/post/2017/08/07/0.9.31-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.32}}
| style="text-align:right;"| 2017-11-07
| style="border-left:0;"| 0.9.32 contains a number of fixes in the router console and associated webapps (addressbook, i2psnark, and susimail). We have also changed the way we handle configured hostnames for published router infos, to eliminate some network enumeration attacks via DNS. Added some checks in the console to resist rebinding attacks.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2017/11/07/0.9.32-Release |title=0.9.32 Release |website=geti2p.net |author=zzz |date=11 November 2017 |access-date=15 November 2017 |archive-date=15 November 2017 |archive-url=https://web.archive.org/web/20171115083159/https://geti2p.net/en/blog/post/2017/11/07/0.9.32-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.33}}
| style="text-align:right;"| 2018-01-30
| style="border-left:0;"| 0.9.33 contains bug fixes for i2psnark, i2ptunnel, streaming, and SusiMail. Updates for reseed proxying, and default rate limiting.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2018/01/30/0.9.33-Release |title=0.9.33 Release |website=geti2p.net |author=zzz |date=30 January 2018 |access-date=30 January 2018 |archive-date=31 January 2018 |archive-url=https://web.archive.org/web/20180131080918/https://geti2p.net/en/blog/post/2018/01/30/0.9.33-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.34}}
| style="text-align:right;"| 2018-04-10
| style="border-left:0;"| 0.9.34 contains bug fixes for i2ptunnel, router console, SusiMail, routing and transport along with Changes to SusiMail and UPnP.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2018/04/10/0.9.34-Release |title=0.9.34 Release |website=geti2p.net |author=zzz |date=10 April 2018 |access-date=11 April 2018 |archive-date=12 April 2018 |archive-url=https://web.archive.org/web/20180412082441/https://geti2p.net/en/blog/post/2018/04/10/0.9.34-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.35}}
| style="text-align:right;"| 2018-06-26
| style="border-left:0;"| 0.9.35 adds support for folders in SusiMail, and a new SSL Wizard for setting up HTTPS on your Hidden Service website.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2018/06/26/0.9.35-Release |title=0.9.35 Release |website=geti2p.net |author=zzz |date=26 June 2018 |access-date=29 June 2018 |archive-date=29 June 2018 |archive-url=https://web.archive.org/web/20180629074152/https://geti2p.net/en/blog/post/2018/06/26/0.9.35-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.36}}
| style="text-align:right;"| 2018-08-23
| style="border-left:0;"| 0.9.36 implements a new, more secure transport protocol called NTCP2. It is disabled by default, but you may enable it for testing. NTCP2 will be enabled in the next release.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2018/08/23/0.9.36-Release |title=0.9.36 Release |website=geti2p.net |author=zzz |date=23 August 2018 |access-date=29 January 2019 |archive-date=27 March 2019 |archive-url=https://web.archive.org/web/20190327150338/https://geti2p.net/en/blog/post/2018/08/23/0.9.36-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.37}}
| style="text-align:right;"| 2018-10-04
| style="border-left:0;"| 0.9.37 enables the faster, more secure transport protocol called NTCP2.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2018/10/04/0.9.37-Release |title=0.9.37 Release |website=geti2p.net |author=zzz |date=4 October 2018 |access-date=29 January 2019 |archive-date=7 January 2019 |archive-url=https://web.archive.org/web/20190107064512/https://geti2p.net/en/blog/post/2018/10/04/0.9.37-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.38}}
| style="text-align:right;"| 2019-01-22
| style="border-left:0;"| 0.9.38 includes a new first-install wizard with a bandwidth tester. We've added support for the latest GeoIP database format. There's a new Firefox profile installer and a new, native Mac OSX installer on our website. Work continues on supporting the new "LS2" netdb format.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2019/01/22/0.9.38-Release |title=0.9.38 Release |website=geti2p.net |author=zzz |date=22 January 2019 |access-date=29 January 2019 |archive-date=29 January 2019 |archive-url=https://web.archive.org/web/20190129181330/https://geti2p.net/en/blog/post/2019/01/22/0.9.38-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.39}}
| style="text-align:right;"| 2019-03-21
| style="border-left:0;"| 0.9.39 includes extensive changes for the new network database types (proposal 123). We've bundled the i2pcontrol plugin as a webapp to support development of RPC applications. There are numerous performance improvements and bug fixes.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2019/03/21/0.9.39-Release |title=0.9.39 Release |website=geti2p.net |author=zzz |date=21 March 2019 |access-date=22 March 2019 |archive-date=22 March 2019 |archive-url=https://web.archive.org/web/20190322040222/https://geti2p.net/en/blog/post/2019/03/21/0.9.39-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.40}}
| style="text-align:right;"| 2019-05-07
| style="border-left:0;"| 0.9.40 includes support for the new encrypted leaseset format. We disabled the old NTCP 1 transport protocol. There's a new SusiDNS import feature, and a new scripted filtering mechanism for incoming connections.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2019/05/07/0.9.40-Release |title=0.9.40 Release |website=geti2p.net |author=zzz |date=7 May 2019 |access-date=7 December 2019 |archive-date=2 August 2019 |archive-url=https://web.archive.org/web/20190802204209/http://www.geti2p.net/en/blog/post/2019/05/07/0.9.40-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.41}}
| style="text-align:right;"| 2019-07-02
| style="border-left:0;"| 0.9.41 continues the work to implement new features for proposal 123, including per-client authentication for encrypted leasesets. The console has an updated I2P logo and several new icons. We've updated the Linux installer.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2019/07/02/0.9.41-Release |title=0.9.41 Release |website=geti2p.net |author=zzz |date=2 July 2019 |access-date=13 August 2019 |archive-date=13 August 2019 |archive-url=https://web.archive.org/web/20190813172736/https://geti2p.net/en/blog/post/2019/07/02/0.9.41-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.42}}
| style="text-align:right;"| 2019-08-28
| style="border-left:0;"| 0.9.42 continues the work to make I2P faster and more reliable. It includes several changes to speed up our UDP transport. We have split up the configuration files to enable future work for more modular packaging. We continue work to implement new proposals for faster and more secure encryption. There are, of course, a lot of bug fixes also.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2019/08/27/0.9.42-Release |title=0.9.42 Release |website=geti2p.net |author=zzz |date=28 August 2019 |access-date=27 September 2020 |archive-date=3 October 2020 |archive-url=https://web.archive.org/web/20201003160409/https://geti2p.net/en/blog/post/2019/08/27/0.9.42-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.43}}
| style="text-align:right;"| 2019-10-22
| style="border-left:0;"| 0.9.43 release continues work on stronger security and privacy features and performance improvements. Our implementation of the new leaseset specification (LS2) is now complete. We are beginning our implementation of stronger and faster end-to-end encryption (proposal 144) for a future release. Several IPv6 address detection issues have been fixed, and there of course are several other bug fixes.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2019/10/22/0.9.43-Release |title=0.9.43 Release |website=geti2p.net |author=zzz |date=22 October 2019 |access-date=23 November 2019 |archive-date=25 November 2019 |archive-url=https://web.archive.org/web/20191125085234/http://geti2p.net/en/blog/post/2019/10/22/0.9.43-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.44}}
| style="text-align:right;"| 2019-12-01
| style="border-left:0;"| 0.9.44 contains an important fix for a denial of service issue in hidden services handling of new encryption types.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2019/12/01/0.9.44-Release |title=0.9.44 Release |website=geti2p.net |author=zzz |date=1 December 2019 |access-date=7 December 2019 |archive-date=5 December 2019 |archive-url=https://web.archive.org/web/20191205200101/https://geti2p.net/en/blog/post/2019/12/01/0.9.44-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.45}}
| style="text-align:right;"| 2020-02-25
| style="border-left:0;"| 0.9.45 contains bug fixes.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2020/02/25/0.9.45-Release |title=0.9.45 Release |website=geti2p.net |author=zzz |date=25 February 2020 |access-date=3 October 2020 |archive-date=21 October 2020 |archive-url=https://web.archive.org/web/20201021044754/http://geti2p.net/en/blog/post/2020/02/25/0.9.45-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.46}}
| style="text-align:right;"| 2020-05-25
| style="border-left:0;"| 0.9.46 contains new ECIES Encryption.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2020/05/25/0.9.46-Release |title=0.9.46 Release |website=geti2p.net |author=zzz |date=25 May 2020 |access-date=3 October 2020 |archive-date=20 September 2020 |archive-url=https://web.archive.org/web/20200920083927/http://geti2p.net/en/blog/post/2020/05/25/0.9.46-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.47}}
| style="text-align:right;"| 2020-08-24
| style="border-left:0;"| 0.9.47 enables new encryption for some services, now requires Java 8 and Sybil analysis and blocking is now enabled by default.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2020/08/24/0.9.47-Release |title=0.9.47 Release |website=geti2p.net |author=zzz |date=24 August 2020 |access-date=9 September 2020 |archive-date=27 August 2020 |archive-url=https://web.archive.org/web/20200827204140/https://geti2p.net/en/blog/post/2020/08/24/0.9.47-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.48}}
| style="text-align:right;"| 2020-11-30
| style="border-left:0;"| 0.9.48 enables new encryption for most services, has significant performance improvements.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2020/11/30/0.9.48-Release |title=0.9.48 Release |website=geti2p.net |author=zzz |date=30 November 2020 |access-date=6 January 2021 |archive-date=20 January 2021 |archive-url=https://web.archive.org/web/20210120192840/https://geti2p.net/en/blog/post/2020/11/30/0.9.48-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.49}}
| style="text-align:right;"| 2021-02-17
| style="border-left:0;"| 0.9.49 improves SSU transport and begins transition to [[Curve25519|X25519]] encryption for routers.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2021/02/17/0.9.49-Release |title=0.9.49 Release |website=geti2p.net |author=zzz |date=17 February 2021 |access-date=13 December 2021 |archive-date=13 December 2021 |archive-url=https://web.archive.org/web/20211213202811/https://geti2p.net/en/blog/post/2021/02/17/0.9.49-Release |url-status=live }}</ref>
|-
! {{Version |o |0.9.50}}
| style="text-align:right;"| 2021-05-17
| style="border-left:0;"| 0.9.50 continues transition to X25519 encryption for routers, enables [[DNS over HTTPS|DoH]] for reseeding and improves support for IPv6.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2021/05/17/0.9.50-Release |title=0.9.50 Release |website=geti2p.net |author=zzz |date=17 May 2021 |access-date=1 June 2021 |archive-date=26 May 2021 |archive-url=https://web.archive.org/web/20210526204212/https://geti2p.net/en/blog/post/2021/05/17/0.9.50-Release |url-status=live }}</ref>
|-
! {{Version |o |1.5.0}}
| style="text-align:right;"| 2021-08-23
| style="border-left:0;"| 1.5.0 adds short tunnel build messages, continues transition to X25519 encryption for routers and improves performance.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2021/08/23/1.5.0-Release |title=1.5.0 Release |website=geti2p.net |author=zzz |date=23 August 2021 |access-date=13 December 2021 |archive-date=13 December 2021 |archive-url=https://web.archive.org/web/20211213202817/https://geti2p.net/en/blog/post/2021/08/23/1.5.0-Release |url-status=live }}</ref>
|-
! {{Version |o |1.6.1}}
| style="text-align:right;"| 2021-11-29
| style="border-left:0;"| 1.6.1{{efn|tagged as 1.6.0}} further accelerates transition to X25519 for routers, enables short tunnel build messages and improves SSU performance.<ref>{{cite web |url=https://geti2p.net/en/blog/post/2021/11/29/1.6.0-Release |title=1.6.1 Release |website=geti2p.net |author=zzz |date=29 September 2021 |access-date=13 December 2021 |archive-date=13 December 2021 |archive-url=https://web.archive.org/web/20211213202806/https://geti2p.net/en/blog/post/2021/11/29/1.6.0-Release |url-status=live }}</ref>
|-
! {{Version |o |1.7.0}}
| style="text-align:right;"| 2022-02-21
| style="border-left:0;"| 1.7.0 improves performance and reliability.<ref>{{cite web | title=1.7.0 Release | website=I2P | date=February 21, 2022 | url=https://geti2p.net/en/blog/post/2022/02/21/1.7.0-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |1.8.0}}
| style="text-align:right;"| 2022-05-23
| style="border-left:0;"| 1.8.0 fixes bugs and adds experimental SSU2 support.<ref>{{cite web | title=1.8.0 Release | website=I2P | date=May 23, 2022 | url=https://geti2p.net/en/blog/post/2022/05/23/1.8.0-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |1.9.0}}
| style="text-align:right;"| 2022-08-22
| style="border-left:0;"| 1.9.0 improves SSU2 support and enables it on Android and ARM devices.<ref>{{cite web | title=1.9.0 Release | website=I2P | date=August 22, 2022 | url=https://geti2p.net/en/blog/post/2022/08/22/1.9.0-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.0.0}}
| style="text-align:right;"| 2022-11-21
| style="border-left:0;"| 2.0.0 enables SSU2 for all users and adds RFC 7616 support.<ref>{{cite web | title=2.0.0 Release | website=I2P | date=November 21, 2022 | url=https://geti2p.net/en/blog/post/2022/11/21/2.0.0-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.1.0}}
| style="text-align:right;"| 2023-01-09
| style="border-left:0;"| 2.1.0 fixes rare implementation bugs with SSU2 and adds torsocks support.<ref>{{cite web | title=2.1.0 Release | website=I2P | date=January 9, 2023 | url=https://geti2p.net/en/blog/post/2023/01/09/2.1.0-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.2.0}}
| style="text-align:right;"| 2023-03-13
| style="border-left:0;"| 2.2.0 adds mitigations for DDOS attacks across the NetDB, Floodfill, and Peer-Selection components. zzz also stepped back as one of the lead maintainers.<ref>{{cite web | title=I2P Release 2.2.0 | website=I2P | date=March 13, 2023 | url=https://geti2p.net/en/blog/post/2023/03/13/new_release_2.2.0 | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.2.1}}
| style="text-align:right;"| 2023-04-12
| style="border-left:0;"| 2.2.1 fixes packaging issues created by the previous release and updates components.<ref>{{cite web | title=I2P Release 2.2.1 | website=I2P | date=April 12, 2023 | url=https://geti2p.net/en/blog/post/2023/04/12/new_release_2.2.1 | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.3.0}}
| style="text-align:right;"| 2023-06-25
| style="border-left:0;"| 2.3.0 fixes CVE-2023-36325 (context-confusion bug which occurred in the bloom filter), adds mitigations to prevent such issues, adds notbob.i2p and ramble.i2p to the console homepage and allows users to override blocklist expiration with an interval.<ref>{{cite web | title=I2P Release 2.3.0 | website=I2P | date=June 25, 2023 | url=https://geti2p.net/en/blog/post/2023/06/25/new_release_2.3.0 | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.4.0}}
| style="text-align:right;"| 2023-12-18
| style="border-left:0;"| 2.4.0 adds DDOS mitigations to NetDB and disables SSU1 support.<ref>{{cite web | title=I2P 2.4.0 Release with Congestion and NetDB Security improvements | website=I2P | date=December 18, 2023 | url=https://geti2p.net/en/blog/post/2023/12/18/i2p-release-2.4.0 | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.5.0}}
| style="text-align:right;"| 2023-12-18
| style="border-left:0;"| 2.5.0 improves compatibility with other Bittorrent clients like qBittorrent.<ref>{{cite web | title=New Release I2P 2.5.0 | website=I2P | date=April 8, 2024 | url=https://geti2p.net/en/blog/post/2024/04/08/new_release_i2p_2.5.0 | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.5.1}}
| style="text-align:right;"| 2024-05-06
| style="border-left:0;"| 2.5.1 adds more mitigations against then ongoing DDOS attacks.<ref>{{cite web | title=New Release I2P 2.5.1 | website=I2P | date=May 6, 2024 | url=https://geti2p.net/en/blog/post/2024/05/06/i2p_2.5.1_released | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.5.2}}
| style="text-align:right;"| 2024-05-15
| style="border-left:0;"| 2.5.2 fixes a bug that truncates HTTP responses.<ref>{{cite web | title=2.5.2 Release | website=I2P | date=May 15, 2024 | url=https://geti2p.net/en/blog/post/2024/05/15/2.5.2-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.6.0}}
| style="text-align:right;"| 2024-07-19
| style="border-left:0;"| 2.6.0 increases the minimum version for floodfill routers and disables I2P over Tor.<ref>{{cite web | title=I2P 2.6.0 Release | website=I2P | date=July 19, 2024 | url=https://geti2p.net/en/blog/post/2024/07/19/2.6.0-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.6.1}}
| style="text-align:right;"| 2024-08-06
| style="border-left:0;"| 2.6.1 fixes a User-Interface bug in the Hidden Services Manager application.<ref>{{cite web | title=2.6.1 Release | website=I2P | date=August 6, 2024 | url=https://geti2p.net/en/blog/post/2024/08/06/2.6.1-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.7.0}}
| style="text-align:right;"| 2024-10-09
| style="border-left:0;"| 2.7.0 fixes bugs and improves performance.<ref>{{cite web | title=I2P 2.7.0 Released | website=I2P | date=October 9, 2024 | url=https://geti2p.net/en/blog/post/2024/10/09/i2p-release-2.7.0 | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.8.0}}
| style="text-align:right;"| 2025-02-03
| style="border-left:0;"| 2.8.0 fixes bugs and improves network stability.<ref>{{cite web | title=I2P 2.8.0 Released | website=I2P | date=February 3, 2025 | url=https://geti2p.net/en/blog/post/2025/02/03/i2p-release-2.8.0 | access-date=April 5, 2025}}</ref>
|-
! {{Version |o |2.8.1}}
| style="text-align:right;"| 2025-03-17
| style="border-left:0;"| 2.8.1 fixes accesses to local sites that were broken in 2.8.0.<ref>{{cite web | title=2.8.1 Release | website=I2P | date=March 17, 2025 | url=https://geti2p.net/en/blog/post/2025/03/17/2.8.1-Release | access-date=April 5, 2025}}</ref>
|-
! {{Version |c |2.8.2}}
| style="text-align:right;"| 2025-03-29
| style="border-left:0;"| 2.8.2 fixes a bug causing SHA256 failures that was introduced in the 2.8.1 release.<ref>{{cite web | title=2.8.2 Release | website=I2P | date=March 29, 2025 | url=https://geti2p.net/en/blog/post/2025/03/29/2.8.2-Release | access-date=April 5, 2025}}</ref>
|-
| colspan="3" | {{Version|l|show=111111}}
|}
|}

== Funding ==
The website states that "funding for I2P comes entirely from donations".<ref>{{Cite web |title=I2P: A scalable framework for anonymous communication – Introduction |url=https://geti2p.net/en/docs/how/tech-intro |url-status=live |archive-url=https://web.archive.org/web/20220314000316/https://geti2p.net/en/docs/how/tech-intro |archive-date=2022-03-14 |access-date=2022-03-14 |website=I2P Website }}</ref> Admins and managers of the project said that "the core project itself doesn't take donations". These should instead go to secondary applications or be spent on hiring others, to work on I2P.<ref>{{Cite web |last=idk aka. eyedeekay |date=2022-03-06 |title=Network privacy via i2p w/ idk and Sadie |url=https://optoutpod.com/episodes/s2e10-i2p/ |access-date=2022-03-14 |website=Opt Out Podcast |at=00:55:43 |archive-date=2022-03-07 |archive-url=https://web.archive.org/web/20220307010619/https://optoutpod.com/episodes/s2e10-i2p/ |url-status=live }}</ref> Support for the [[onboarding]] for I2P came from the ''[[Open Technology Fund]]''.<ref>{{Cite web |last=Mascis |first=Sadie |date=2022-03-06 |title=Network privacy via i2p w/ idk and Sadie" |url=https://optoutpod.com/episodes/s2e10-i2p/ |access-date=2022-03-13 |website=Opt Out Podcast |at=00:54:20 |archive-date=2022-03-07 |archive-url=https://web.archive.org/web/20220307010619/https://optoutpod.com/episodes/s2e10-i2p/ |url-status=live }}</ref><ref>{{Cite web |last=Open Technology Fund |author-link=Open Technology Fund |title=5G and Human Rights |url=https://www.opentech.fund/results/supported-projects/5g-and-human-rights/ |access-date=2022-03-14 |website=Open Technology Fund Website |date=4 January 2022 |publisher=[[U.S. Agency for Global Media]] |archive-date=2022-03-14 |archive-url=https://web.archive.org/web/20220314022625/https://www.opentech.fund/results/supported-projects/5g-and-human-rights/ |url-status=live }}</ref> In contrast to ''[[The Tor Project]]'', I2P has "not the financial or legal infrastructure to support a network of [[Tor (network)|exit nodes]]".<ref>{{Cite web |last=idk aka. eyedeekay |date=2022-03-06 |title=Network privacy via i2p w/ idk and Sadie |url=https://optoutpod.com/episodes/s2e10-i2p/ |access-date=2022-03-13 |website=Opt Out Podcast |at=00:34:20 |archive-date=2022-03-07 |archive-url=https://web.archive.org/web/20220307010619/https://optoutpod.com/episodes/s2e10-i2p/ |url-status=live }}</ref> The reseed servers,<ref>{{Cite web |title=How to Set up a Reseed Server |url=https://geti2p.net/en/get-involved/guides/reseed |access-date=2022-03-13 |website=I2P Website |archive-date=2022-03-14 |archive-url=https://web.archive.org/web/20220314022059/https://geti2p.net/en/get-involved/guides/reseed |url-status=live }}</ref> a sort of bootstrap nodes,<ref>{{Cite web |title=How to volunteer by helping I2P-Bote bootstrap – Blog |url=https://geti2p.net/en/blog/post/2019/05/25/help-bootstrap-bote |access-date=2022-03-13 |website=I2p Website |archive-date=2022-04-07 |archive-url=https://web.archive.org/web/20220407054348/https://geti2p.net/en/blog/post/2019/05/25/help-bootstrap-bote |url-status=live }}</ref> which connect the user with the initial set of peers to join the I2P-network, should be run by volunteers.<ref>{{Cite web |last=idk aka. eyedeekay |date=2022-03-06 |title=Network privacy via i2p w/ idk and Sadie |url=https://optoutpod.com/episodes/s2e10-i2p/ |access-date=2022-03-13 |website=Opt Out Podcast |at=00:57:00 |archive-date=2022-03-07 |archive-url=https://web.archive.org/web/20220307010619/https://optoutpod.com/episodes/s2e10-i2p/ |url-status=live }}</ref>

== Software ==
[[File:I2P router console 0.9.31-0.png|thumb|I2P 0.9.31-0 router console]]

Since I2P is an anonymizing [[network layer]], it is designed so other software can use it for anonymous communication. As such, there are a variety of tools currently available for I2P or in development.

The I2P [[Router (computing)|router]] is controlled through the router console, which is a web frontend accessed through a web browser.

=== General networking ===
* ''I2PTunnel'' is an application embedded into I2P that allows arbitrary TCP/IP applications to communicate over I2P by setting up "[[Tunneling protocol|tunnels]]" which can be accessed by connecting to pre-determined ports on [[localhost]].
* ''SAM'' (''Simple Anonymous Messaging'') is a [[Communications protocol|protocol]] which allows a client application written in any [[programming language]] to communicate over I2P, by using a socket-based interface to the I2P router.<ref>{{Citation | title = API | contribution-url = https://geti2p.net/en/docs/api/sam | contribution = SAM | publisher = I2P | access-date = 2013-12-24 | archive-date = 2013-12-24 | archive-url = https://web.archive.org/web/20131224112749/https://geti2p.net/en/docs/api/sam | url-status = live }}.</ref>
* ''BOB'' (''Basic Open Bridge'') is a less complex app to router protocol similar to "SAM"<ref>{{Citation | title = API | contribution-url = https://geti2p.net/en/docs/api/bob | contribution = BOB | publisher = Get I2P | access-date = 2013-12-24 | archive-date = 2013-12-24 | archive-url = https://web.archive.org/web/20131224112753/https://geti2p.net/en/docs/api/bob | url-status = live }}.</ref>
* ''Orchid'' Outproxy [[Tor (anonymity network)|Tor]] plugin<ref>{{cite web|url=https://github.com/subgraph/Orchid|title=GitHub – subgraph/Orchid|date=7 March 2019|via=GitHub|access-date=20 October 2017|archive-date=9 August 2017|archive-url=https://web.archive.org/web/20170809050525/https://github.com/subgraph/Orchid|url-status=live}}</ref>
* As of version 2.6.0, released in July 2024, I2P no longer allows I2P access over Tor connections.<ref>{{Cite web |last=idk |title=I2P 2.6.0 Release - Blog - I2P |url=https://geti2p.net/en/blog/post/2024/07/19/2.6.0-Release |url-status=live |archive-url=https://web.archive.org/web/20240721131455/https://geti2p.net/en/blog/post/2024/07/19/2.6.0-Release |archive-date=2024-07-21 |access-date=2024-07-21 |website=geti2p.net}}</ref>

=== Chat ===
* Any [[IRC client]] made for the Internet Relay Chat can work, once connected to the I2P [[IRC server]] (on localhost). I2P have the option to create tunnels that are specific for this usage, where certain commands that could de-anonymize the user are filtered out.
* Some [[XMPP]] clients like [[Gajim]], [[Pidgin (software)|Pidgin]] or a modified [[Conversations (software)|Conversations]] client<ref>{{Citation |last=R4SAS |title=r4sas/Conversations-I2P |date=2024-04-02 |url=https://github.com/r4sas/Conversations-I2P |access-date=2024-05-24}}</ref> can work with I2P XMPP servers using [[Prosody (software)|Prosody]] that are using the mod_darknet module<ref>{{Cite web |title=Decentralized instant messenger (XMPP aka Jabber) - i2pd documentation |url=https://i2pd.readthedocs.io/en/latest/tutorials/xmpp/ |access-date=2024-05-24 |website=i2pd.readthedocs.io}}</ref>

=== File sharing ===
* Several programs provide [[BitTorrent (protocol)|BitTorrent]] functionality for use within the I2P network.  Users cannot connect to non-I2P torrents or peers from within I2P, nor can they connect to I2P torrents or peers from outside I2P.<ref>{{Citation | place = [[Germany|DE]] | url = https://forum.i2p2.de/viewtopic.php?t=2068 | title = I2P Bittorrent FAQ | publisher = i2p2 | type = forum | url-status = dead | archive-url = https://web.archive.org/web/20111103091108/http://forum.i2p2.de/viewtopic.php?t=2068 | archive-date = 2011-11-03 }}.</ref> ''I2PSnark'', included in the I2P install package, is a port of the BitTorrent client named Snark.<ref>{{Citation | url = http://klomp.org/snark/ | title = The Hunting of the Snark Project – BitTorrent Application Suite | publisher = Klomp | access-date = 2013-12-22 | archive-date = 2013-11-24 | archive-url = https://web.archive.org/web/20131124085714/http://www.klomp.org/snark/ | url-status = live }}.</ref> ''[[Vuze]]'', formerly known as Azureus, is a [[BitTorrent client]] that includes a plugin for I2P, allowing anonymous swarming through this network.<ref>{{Citation | url = http://wiki.vuze.com/w/I2PHelper_HowTo | title = I2PHelper | contribution = How To for I2P Network Plugin | format = Howto | type = setup tutorial | publisher = Vuze | access-date = 2015-02-23 | archive-date = 2015-02-25 | archive-url = https://web.archive.org/web/20150225030106/http://wiki.vuze.com/w/I2PHelper_HowTo | url-status = live }}.</ref> This plugin is still in an early stage of development, however it is already fairly stable. ''I2P-BT'' is a BitTorrent client for I2P that allows anonymous swarming for [[file sharing]]. This client is a modified version of the original BitTorrent 3.4.2 program which runs on [[Microsoft|MS]] Windows and most dialects of [[Unix]] in a GUI and command-line environment. It was developed by the individual known as 'duck' on I2P in cooperation with 'smeghead'. It is no longer being actively developed; however, there is a small effort to upgrade the I2P-BT client up to par with the BitTorrent 4.0 release. ''I2PRufus'' is an I2P port of the Rufus BitTorrent client.<ref>{{cite web | url = http://rufus.sourceforge.net/ | title = Rufus – BitTorrent Client | work = Sourceforge | access-date = 2006-09-06 | archive-date = 2010-01-07 | archive-url = https://web.archive.org/web/20100107002810/http://rufus.sourceforge.net/ | url-status = live }}.</ref> [[Robert (P2P Software)]] is the most actively maintained I2PRufus fork. XD is a standalone BitTorrent client written in Go.<ref>{{cite web|url=https://github.com/majestrate/XD|title=GitHub – majestrate/XD: i2p bittorrent client.|date=22 March 2019|via=GitHub|access-date=2 November 2017|archive-date=29 July 2017|archive-url=https://web.archive.org/web/20170729192542/https://github.com/majestrate/XD|url-status=live}}</ref>  BiglyBT is a bittorrent client based on Vuze which also allows the use of i2p for downloading/seeding. Additionally, there exists a torrent index named ''Postman'', ran by the individual with the same name, its rules says that it does not allow illegal content, but [[warez]] and [[Piracy (media)|piracy]] is accepted.
*  Two [[Kad network]] clients exist for the I2P network, ''iMule'' and ''Nachtblitz''. iMule (''invisible Mule'') is a port of [[eMule]] for I2P network. iMule has not been developed since 2013. iMule is made for anonymous file sharing. In contrast to other [[eDonkey network|eDonkey]] clients, iMule only uses the [[Kademlia]] for proceeding to connect through I2P network, so no servers are needed. ''Nachtblitz''<ref>{{cite web | url=http://files.i2p-projekt.de/misc/nachtblitz/ | title=Official Nachtblitz Resource | access-date=2022-11-01 | archive-date=2022-11-01 | archive-url=https://web.archive.org/web/20221101080841/http://files.i2p-projekt.de/misc/nachtblitz/ | url-status=live }}</ref> is a custom client built on the .NET Framework. The latest version is 1.4.27, released on March 23, 2016. Nachtblitz includes a time lock to disable the software one year after its release date.
* [[I2Phex]] is a port of the popular [[Gnutella]] client [[Phex]] to I2P. It is stable and fairly functional.
* [[Tahoe-LAFS]] has been ported to I2P. This allows for files to be anonymously stored in Tahoe-LAFS grids.
* MuWire is a file-sharing program inspired by the LimeWire Gnutella client that works atop the I2P network.<ref>{{Cite web|url=https://www.reddit.com/r/i2p/comments/bvamf1/introducing_muwire_a_filesharing_application_for/|title=r/i2p – Introducing MuWire – a file-sharing application for I2P|website=reddit|date=31 May 2019|language=en-US|access-date=2019-12-17|archive-date=2022-04-07|archive-url=https://web.archive.org/web/20220407054312/https://www.reddit.com/r/i2p/comments/bvamf1/introducing_muwire_a_filesharing_application_for/|url-status=live}}</ref>

==== Bridging to clearnet ====
Currently, [[Vuze]] and BiglyBT are the torrent clients that make [[Clearnet (networking)|clearnet]] (connections not through I2P) torrents available on I2P and vice versa. Depending on the client settings, torrents from the internet can be made available on I2P (via announcements to I2P's DHT network) and torrents from I2P can be made available to the internet. For this reason, torrents previously published only on I2P can be made available to the entire Internet, and users of I2P can often download popular content from the Internet while maintaining the anonymity of I2P. As of August 2022, the default outproxy is exit.stormycloud.i2p which is run by StormyCloud Inc.<ref>{{cite web |url=https://torrentfreak.com/vuze-speeds-up-torrent-downloads-through-swarm-merging-150320/ |title=Vuze Speeds Up Torrent Downloads Through "Swarm Merging" |date=20 March 2015 |work=[[TorrentFreak]] |access-date=4 June 2016 |archive-date=17 October 2017 |archive-url=https://web.archive.org/web/20171017233439/https://torrentfreak.com/vuze-speeds-up-torrent-downloads-through-swarm-merging-150320/ |url-status=live }}</ref><ref>{{cite web |url=https://wiki.vuze.com/w/I2PHelper_HowTo#Network_Mixing |title=I2PHelper HowTo |work=VuzeWiki |access-date=4 June 2016 |archive-date=20 October 2017 |archive-url=https://web.archive.org/web/20171020084042/https://wiki.vuze.com/w/I2PHelper_HowTo#Network_Mixing |url-status=live }}</ref><ref>{{Cite web |title=StormyCloud – I2P Outproxy {{!}} I2P Anonymous Network |url=https://stormycloud.org/i2p-outproxy/ |access-date=2023-07-24 |website=stormycloud.org}}</ref>

=== Email ===
{{unreferenced section|date=February 2024}}
[[File:I2PBote-inbox-0.4.png|thumb|A screenshot of the inbox of I2P-Bote.]]
* ''I2P-Bote'' is a [[Free and open-source software|free]], fully [[Decentralized computing|decentralized]] and distributed anonymous [[email system]] with a strong focus on security.<ref>{{Citation |title=i2p/i2p.i2p-bote |date=2024-03-06 |url=https://github.com/i2p/i2p.i2p-bote |access-date=2024-03-08 |publisher=The I2P Project}}</ref> It supports multiple identities and does not expose email [[metadata]]. {{As of | 2015}}, it is still considered [[beta version|beta software]]. I2P-Bote is accessible via the I2P [[web application|web console]] interface or using standard email protocols (i.e. [[IMAP]]/[[SMTP]]). All bote-mails are transparently end-to-end encrypted and signed by the sender's private key, thus removing the need for [[Pretty Good Privacy|PGP]] or other email encryption software. I2P-Bote offers additional anonymity by allowing for the use of mail relays with variable length delays. Since it is decentralized, there is no centralized email server that could correlate different email identities as communicating with each other (i.e. ''profiling''). Even the [[Node (networking)|nodes]] relaying the mails do not know the sender, and apart from sender and receiver, only the end of the high-[[Network latency|latency]] mail route and the storing nodes will know to whom (which I2P-Bote address – the user's IP address is still hidden by I2P) the mail is destined. The original sender could have gone offline long before the email becomes available to the recipient. No account registration is necessary, all you have to do in order to use it is create a new identity. I2P-Bote can be installed as an I2P plugin .<ref>{{Citation |title=i2p/i2p.i2p-bote |date=2024-09-20 |url=https://github.com/i2p/i2p.i2p-bote |access-date=2024-10-13 |publisher=The I2P Project}}</ref>
* I2P also has a free pseudonymous e-mail service run by an individual called ''Postman''. Susimail is a [[web-based]] email client intended primarily for use with Postman's mail servers, and is designed with security and anonymity in mind. Susimail was created to address privacy concerns in using these servers directly using traditional email clients, such as leaking the user's hostname while communicating with the SMTP server. It is currently included in the default I2P distribution, and can be accessed through the I2P router console web interface. Mail.i2p can contact both I2P email users and public internet email users.
* [[Bitmessage#Bitmessage.ch|Bitmessage.ch]] can be used over I2P{{cn|date=February 2024}}

=== Instant messaging ===
* ''I2P-Messenger'' is a simple [[Qt (framework)|Qt]]-based, serverless, [[end-to-end-encrypted]] [[instant messenger]] for I2P.<ref>{{Citation | title = Introducing I2P | url = https://geti2p.net/en/docs/how/tech-intro#app.i2pmessenger | date = Nov 10, 2015 | access-date = November 11, 2015 | archive-date = November 25, 2015 | archive-url = https://web.archive.org/web/20151125093633/https://geti2p.net/en/docs/how/tech-intro#app.i2pmessenger | url-status = live }}</ref> No servers can log the user's conversations. No ISP can log with whom the user chats, when, or for how long. As it is serverless, it can make use of I2P's end-to-end encryption, preventing any node between two parties from having access to the plain text. I2P-Messenger can be used for fully anonymous instant communication with persons the user doesn't even know, or, alternatively, to communicate securely and untraceably with friends, family members, or colleagues. <!--"Thus, it is also a useful tool against data retention in a surveillance society" Is this the part that is soapboxy?--> In addition to messaging, [[file transfer]] is also supported.
* ''I2P-Talk'' is another simple instant messenger incompatible with I2P-Messenger, but having the same security properties

=== Publishing ===
* ''[[Syndie]]'' is a content distribution application, suitable for [[blogs]], [[newsgroups]], [[Internet forum|forums]] and small media attachments. Syndie is designed for [[Resilience (network)|network resilience]]. It supports connections to I2P, the Tor network (Syndie does not support Socks proxies, workaround needed for Tor access), Freenet and the regular internet. Server connections are intermittent, and support [[Network performance#Examples of latency or throughput dominated systems|higher-latency communications]]. Connections can be made to any number of known servers. Content is spread efficiently using a [[Gossip protocol]].
* ''Aktie'' is an anonymous file sharing and distributed [[web of trust]] forums system.  Aktie can connect to I2P with its internal router or use an external router. To fight spam, "hash payments" (proof of CPU work) is computed for every published item.

=== Routers ===
{{Expand section
|small=no
|talksection=Talk:I2P#i2pd
|1=i2pd|date=May 2024}}
* i2pd is a light-weight I2P router written in [[C++]], stripping the excessive applications such as e-mail, torrents, and others that can be regarded as bloat.<ref>{{Cite web|url=https://github.com/PurpleI2P/i2pd/wiki/Differences-between-i2pd-and-Java-I2P-router|title=PurpleI2P/i2pd|website=GitHub|language=en|access-date=2018-08-20|archive-date=2018-10-04|archive-url=https://web.archive.org/web/20181004010416/https://github.com/PurpleI2P/i2pd/wiki/Differences-between-i2pd-and-Java-I2P-router|url-status=live}}</ref><ref>{{Cite web|url=https://i2pd.website/|title=Invisible Internet Protocol Daemon|website=i2pd.website|access-date=2018-08-20|archive-date=2018-08-20|archive-url=https://web.archive.org/web/20180820074847/https://i2pd.website/|url-status=live}}</ref> The I2PSnark standalone [[BitTorrent]] client by I2P+ Team can still be used with it.

=== The Privacy Solutions project ===
The Privacy Solutions project,<ref>{{Citation | url = https://privacysolutions.no/ |archive-url=https://web.archive.org/web/20180419070653/https://privacysolutions.no/ | archive-date=19 April 2018 | title = Privacy Solutions project |url-status=dead }}.</ref> a new organization that develops and maintains I2P software, launched several new development efforts designed to enhance the privacy, security, and anonymity for users, based on I2P protocols and technology.

These efforts include:<ref>{{Citation | url = https://geti2p.net/en/blog/post/2014/08/15/The-privacy-solutions-project | title = List of ongoing Privacy Solutions projects | access-date = 2022-08-27 | archive-date = 2021-05-07 | archive-url = https://web.archive.org/web/20210507043156/https://geti2p.net/en/blog/post/2014/08/15/The-privacy-solutions-project | url-status = live }}.</ref>
* The Abscond browser bundle.
* i2pd,<ref>{{cite web|url=https://i2pd.website/|title=Invisible Internet Protocol Daemon|website=i2pd.website|access-date=2018-08-20|archive-date=2018-08-20|archive-url=https://web.archive.org/web/20180820074847/https://i2pd.website/|url-status=live}}</ref> an alternate implementation of I2P, written in C++ (rather than Java).
* The "BigBrother" I2P [[network monitoring]] project.

The code repository and download sections for the i2pd and Abscond project is available for the public to review and download.<ref>{{Citation | url = https://github.com/PrivacySolutions/i2pd | title = Active development | date = 22 September 2022 | publisher = The Privacy Solutions | access-date = 16 January 2015 | archive-date = 12 November 2014 | archive-url = https://web.archive.org/web/20141112055632/https://github.com/PrivacySolutions/i2pd/ | url-status = live }}</ref>
Effective January, 2015 i2pd is operating under PurpleI2P.<ref>{{Citation | url = https://github.com/PurpleI2P/i2pd | title = Active development | date = 22 September 2022 | publisher = Purple I2P | access-date = 7 February 2016 | archive-date = 4 February 2016 | archive-url = https://web.archive.org/web/20160204015155/https://github.com/PurpleI2P/i2pd/ | url-status = live }}</ref>

===Android===
[[File:I2PAndroid-console-0.9.20.png|thumb|I2P running on [[Android (operating system)|Android]].]]
* Release builds of an I2P Router application for Android can be found on the [[Google Play]] store under The Privacy Solutions Project's Google Play account or on an [[F-Droid]] repository hosted by the developers.<ref>{{Citation | url=https://geti2p.net/en/blog/post/2014/12/01/Android-app-releases | title=Android App Releases | access-date=2014-12-15 | archive-date=2014-12-15 | archive-url=https://web.archive.org/web/20141215232812/https://geti2p.net/en/blog/post/2014/12/01/Android-app-releases | url-status=live }}</ref>
* ''Nightweb'' is an Android application that utilizes I2P and Bittorrent to share blog posts, photos, and other similar content. It can also be run as a desktop application. It is no longer in development.<ref>{{Citation | url = https://sekao.net/nightweb/blog/discontinued.html | title = Discontinued | publisher = Nightweb | access-date = 2015-04-26 | archive-date = 2017-07-04 | archive-url = https://web.archive.org/web/20170704230216/https://sekao.net/nightweb/blog/discontinued.html | url-status = live }}.</ref>

===Cryptocurrency===
Some cryptocurrencies that support I2P are listed below.
<!-- LIST ONLY CURRENCIES THAT ALREADY HAVE WIKIPEDIA ARTICLES -->
* [[Bitcoin]]<ref>{{Cite web|title=Add I2P support using I2P SAM by vasild · Pull Request #20685 · bitcoin/bitcoin|url=https://github.com/bitcoin/bitcoin/pull/20685|access-date=2021-04-03|website=GitHub|language=en|archive-date=2021-03-03|archive-url=https://web.archive.org/web/20210303154106/https://github.com/bitcoin/bitcoin/pull/20685|url-status=live}}</ref>
* [[Monero]]
* [[Verge (cryptocurrency)|Verge]]

== Terminology ==
[[File:Itoopie.svg|thumb|I2P's mascot, itoopie, who is looking through a magnifying glass.<ref>{{cite web |title=I2P con 2015 – Growing the Network, Spreading the Word, 03:41 |url=https://www.youtube.com/watch?v=_R85duCOWsY&t=221 |website=YouTube | date=2 September 2015 |access-date=2018-06-30 |archive-date=2022-04-07 |archive-url=https://web.archive.org/web/20220407054311/https://www.youtube.com/watch?v=_R85duCOWsY&t=221 |url-status=live }}</ref>]]

; Eepsite: Eepsites are [[website]]s that are hosted anonymously within the I2P network.  Eepsite names end in ''.i2p'', such as ''ugha.i2p'' or ''forum.i2p''. EepProxy can locate these sites through the [[Key (cryptography)|cryptographic identifier keys]] stored in the [[hosts (file)|hosts]].txt file found within the I2P program directory.  Typically, I2P is required to access these eepsites.<ref name=":0">{{cite web |url=https://geti2p.net/en/about/intro |title=Intro |work=I2P |access-date=4 June 2016 |archive-date=6 April 2016 |archive-url=https://web.archive.org/web/20160406110604/https://geti2p.net/en/about/intro |url-status=live }}</ref>
; .i2p: 'I2p' is a [[pseudo-top-level domain]] which is only valid within the I2P [[overlay network]] scope. <code>.i2p</code> [[Name resolution (computer systems)|names are resolved]] by browsers by submitting requests to EepProxy which will resolve names to an I2P peer key and will handle data transfers over the I2P network while remaining transparent to the browser.<ref>{{cite web |url=https://geti2p.net/en/docs/naming |title=Naming and Addressbook – I2P |work=geti2p.net |access-date=4 June 2016 |archive-date=29 March 2016 |archive-url=https://web.archive.org/web/20160329181138/https://geti2p.net/en/docs/naming |url-status=live }}</ref>
; EepProxy: The EepProxy program handles all communication between the browser and any eepsite.  It functions as a [[proxy server]] that can be used by any [[web browser]].
; Peers, I2P nodes: Other machines using I2P that are connected to user's machine within the network.  Each machine within the network shares the routing and forwarding of encrypted [[Network packet|packets]].
; Tunnels: Every ten minutes, a connection is established between the user's machine and another peer.  Data to and from the user, along with the data for other peers (routed through the user's machine), pass through these tunnels and are forwarded to their final destination (may include more [[Jump Server|jumps]]).<ref>{{cite web |url=https://geti2p.net/en/docs/how/tunnel-routing |title=Tunnel Routing |work=I2P |access-date=4 June 2016 |archive-date=26 March 2016 |archive-url=https://web.archive.org/web/20160326160508/https://geti2p.net/en/docs/how/tunnel-routing |url-status=live }}</ref>
; netDb: The [[distributed hash table]] (DHT) [[database]] based on the [[Kademlia]] [[algorithm]] that holds information on I2P nodes and I2P eepsites. This database is split up among routers known as "floodfill routers".  When a user wants to know how to contact an eepsite, or where more peers are, they query the [[database]].<ref>{{cite web |url=https://geti2p.net/en/docs/how/network-database |title=The Network Database |work=I2P |access-date=4 June 2016 |archive-date=7 March 2016 |archive-url=https://web.archive.org/web/20160307163119/https://geti2p.net/en/docs/how/network-database |url-status=live }}</ref><ref name=":0" />

==Vulnerabilities==
[[Denial-of-service attack|Denial of service attacks]] are possible against websites hosted on the network, though a site operator may secure their site against certain versions of this type of attack to some extent.<ref>{{Cite web|last=Kack|first=Christopher|date=2012-09-11|title=Layer 7 DOS against I2P darknet|url=http://blog.kejsarmakten.se/all/projects/2012/09/11/dark-loris.html|url-status=dead|archive-url=https://web.archive.org/web/20121014004908/http://blog.kejsarmakten.se/all/projects/2012/09/11/dark-loris.html|archive-date=2012-10-14|access-date=2021-03-13|website=Kejsarmakten:Development}}</ref><ref name=":1">{{Cite journal|last1=Bazli|first1=Behnam|last2=Wilson|first2=Maxim|last3=Hurst|first3=William|date=2017-01-01|title=The dark side of I2P, a forensic analysis case study|journal=Systems Science & Control Engineering|volume=5|issue=1|pages=278–286|doi=10.1080/21642583.2017.1331770|doi-access=free}}</ref>

A [[Zero-day (computing)|zero-day vulnerability]] was discovered for I2P in 2014, and was exploited to [[Data re-identification|de-anonymize]] at least 30,000 users. This included users of the operating system [[Tails (operating system)|Tails]].<ref>{{Cite web|last=Storm|first=Darlene|date=2014-07-24|title=Zero-day broker exploits vulnerability in I2P to de-anonymize Tails users|url=https://www.computerworld.com/article/2476563/zero-day-broker-exploits-vulnerability-in-i2p-to-de-anonymize-tails-users.html|url-status=live|access-date=2021-03-13|website=[[Computerworld]]|language=en|archive-date=2020-09-29|archive-url=https://web.archive.org/web/20200929102557/https://www.computerworld.com/article/2476563/zero-day-broker-exploits-vulnerability-in-i2p-to-de-anonymize-tails-users.html}}</ref> This vulnerability was later patched.<ref>{{Cite web|date=2014-07-29|title=I2P patched against de-anonymizing 0-day, Tails integration still to follow|url=https://www.helpnetsecurity.com/2014/07/29/i2p-patched-against-de-anonymizing-0-day-tails-integration-still-to-follow/|access-date=2021-03-13|website=Help Net Security|language=en-US|archive-date=2020-12-10|archive-url=https://web.archive.org/web/20201210174852/https://www.helpnetsecurity.com/2014/07/29/i2p-patched-against-de-anonymizing-0-day-tails-integration-still-to-follow/|url-status=live}}</ref><ref>{{Cite web|title=0.9.14 Release – Blog – I2P|url=https://geti2p.net/en/blog/post/2014/07/26/0.9.14-Release|access-date=2021-03-13|website=geti2p.net|archive-date=2021-04-22|archive-url=https://web.archive.org/web/20210422103231/https://geti2p.net/en/blog/post/2014/07/26/0.9.14-Release|url-status=live}}</ref>

A 2017 study examining how [[Forensic science|forensic investigators]] might exploit vulnerabilities in I2P software to gather useful evidence indicated that a seized machine which had been running I2P router software may hold unencrypted local data that could be useful to [[law enforcement]]. Records of which websites a user of a later-seized machine was interested in may also be inferred. The study identified a "trusted" I2P [[Domain name registrar|domain registrar]] ("NO.i2p") which appeared to have been abandoned by its administrator, and which the study identified as a potential target for law enforcement takeover. It alternatively suggested waiting for NO.i2p's server to fail, only to [[Social engineering (security)|social engineer]] the I2P community into moving to a phony replacement. Another suggestion the study proposed was to register a mirror version of a target website under an identical domain.<ref name=":1" />

== I2PCon ==

[[File:I2PCon-2015-David-Dagon.jpg|thumb|David Dagon presenting at the first I2Pcon.]]

From {{daterange|{{Format date|2015|08|15}}|{{Format date|2015|08|16}}}} an I2P convention was held in [[Toronto|Toronto, Ontario]].<ref>{{cite web |url=https://geti2p.net/en/blog/post/2015/08/20/I2PCon_Mission_Accomplished |title=I2PCon: Mission Accomplished – Blog |work=I2P |access-date=4 June 2016 |archive-date=10 June 2016 |archive-url=https://web.archive.org/web/20160610211015/https://geti2p.net/en/blog/post/2015/08/20/I2PCon_Mission_Accomplished |url-status=live }}</ref>  The conference was hosted by a local [[hackerspace]], Hacklab. The conference featured presentations from I2P developers and security researchers.

== See also ==
{{div col|colwidth=30em}}
* [[Crypto-anarchism]]
* [[Deep web]]
* [[Darknet]]
* [[Garlic routing]]
* [[Key-based routing]]
* [[Public-key cryptography]]
* [[Rendezvous protocol]]
* [[Secure communication]]
* [[Threat model]]
{{div col end}}

===Software===
{{div col |colwidth=30em}}
* [[Freenet]]
* [[Mixnet]]
* [[Retroshare]]
* [[Tor (network)|Tor]]
* [[Tribler]]
* [[ZeroNet]]
{{div col end}}

== References ==
{{Reflist|2|refs = EXCHANGED.i2p}}
{{Notelist}}

== External links ==
* {{official website}}
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{{I2P|state=expanded}}
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