comparison of instant messaging protocols

!Creator

!First public release date

!License

!Identity (not inc. alias)

!Asynchronous message relaying

!Transport Layer Security

!End-to-end encryption

!Unlimited number of contacts

!Bulletins to all contacts

!One-to-many routing{{efn|name=fn_4}}

!Spam protection

!Group, channel or conference support

!Audio/VoIP support

!Webcam/Video

!Batch file sharing

!Media synchronization

!Serverless{{efn|name=fn_6}}

!Binary format

!Protocol

| Friedhelm Hillebrand

| 1985

| {{Proprietary}}

| Phone number (e.g. +15550123)

| {{Yes}}

| {{No}}

| {{No}}

| About 250 contacts in SIM, unlimited from phone.

| {{No}}

| serial messages

| {{partial|Medium}}

| {{No}}

| {{yes}}

| {{yes|3G-324M/ViLTE}}

| {{yes|RCS}}

| {{No}}

| {{dunno}}

| {{dunno}}

! 3GPP standards

| Jonathan Warren

| 2012 Nov

| {{free|Open standard}}

| Alphanumeric address

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{Yes}} (through proof-of-work)

| {{Yes}}

| {{No}}

| {{No}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{dunno}}

!Bitmessage

| Apple Inc.

| 2002 August

| {{Proprietary}} Freeware; portions under the Apache license

| Username

| {{No}}

| {{No}}

| {{No}}

| {{yes}}

| {{No}}

| {{Yes|multicast}}

| {{partial|Medium}}

| {{No}}

| {{No}}

| {{No}}

| {{yes}}

| {{No}}

| {{yes}}

| {{dunno}}

!Bonjour

|Briarproject.org

| 2018 May 9

|{{free|Open standard}}

|Public & Private key (via QR Codes)

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{Yes}}

| {{dunno}}

!Briar

| Discord Inc.

| 2015 May 13

| {{Proprietary}}

| Discord ID{{Cite web|title=Where can I find my User/Server/Message ID?|url=https://support.discord.com/hc/pl/articles/206346498-Where-can-I-find-my-User-Server-Message-ID-|website=discord.com|language=en}}

| {{yes}}

| {{no}}

| {{no}}

| {{no}}{{cite web|title=Increase the Discord FRIENDS List Limits from 1000 to 2000 or more!|url=https://support.discord.com/hc/en-us/community/posts/4407590964247-Increase-the-Discord-FRIENDS-List-Limits-from-1000-to-2000-or-more-}}

| {{no}}

| {{dunno}}

| {{partial|Medium}}

| {{dunno}}

| {{yes}}

| {{yes}}

| {{yes}}

| {{dunno}}

| {{no}}

| {{dunno}}

!Discord

|corpus.io / dm3.network

|2022

| {{free|Open Source (BSD)}}

|ENS (Ethereum Name Service)

| {{yes}}

| {{yes}}

| {{yes}}

| {{yes}}

| {{yes}}

| {{yes}}

| {{yes}}

| {{yes}}

| {{no}}

| {{no}}

| {{no}}

| {{yes}}

| {{yes}}

| {{dunno}}

!dm3

| spot-on.sf.net / goldbug.sf.net

| 2013

| {{free|Open standard}}

| Key

| {{Yes}}

| {{optional}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{dunno}}

!Echo

| GG Network

| 2000 Jul 17

| {{Proprietary}}

| UIN
e.g. 12345678

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{No}}

| {{No|Centralistic}}

| {{Yes}}{{efn|name=fn_5}} (simple)

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{dunno}}

!Gadu-Gadu

| Jarkko Oikarinen

| 1988 Aug

| {{free|Open standard}}

| Nickname!Username@hostname
(or "hostmask")
e.g. user!~usr@a.b.com{{efn|name=fn_1}}

| {{yes2|Yes, via IRCv3{{cite web |title=chathistory Extension |url=https://ircv3.net/specs/extensions/chathistory |website=ircv3.net |access-date=25 February 2023}} or MemoServ that differs from the main system}}

| {{optional}}

| {{lost|Many implementations which are mostly non-interoperable with other IRC clients}}{{cite web |last1=Gioia |first1=Antonio |title=IRC with SSL and OTR encryption |url=https://www.antoniogioia.com/irc-with-ssl-and-otr/ |access-date=28 December 2023}}{{cite web |title=Secure encryption layer for the IRC protocol based on OpenPGP. |url=https://weechat.org/scripts/source/ircrypt.py.html/}}{{cite web |title=encrypted DCC - SDCC - SCHAT |url=https://forums.mirc.com/ubbthreads.php/topics/234584/encrypted-dcc-sdcc-schat}}

| {{No}}{{efn|name=fn_3|Scalability issue: The protocol gets increasingly inefficient with the number of contacts.{{#tag:ref|{{IETF RFC|1324}}, D. Reed, 1992. 2.5.1, Size}}{{#tag:ref|[http://www.psyc.eu/synconf Functionality provided by systems for synchronous conferencing], C.v. Loesch, 1992. 1.2.1 Growth}}}}

| {{No}}

| {{Yes|Simplistic multicast}}

| {{partial|Medium}}

| {{Yes}} (everyone, multiple simultaneous, any size)

| {{lost|many implementations which are incompatible with other IRC clients{{cite web |title=dcc.voice |url=http://www.kvirc.net/doc/cmd_dcc.voice.html |website=kvirc.net |access-date=25 February 2023}}{{cite web |title=VoIRC |website=GitHub |url=https://github.com/asiekierka/voirc}}}}

| {{No}}

| {{Yes}}

| {{partial|via BNC}}

| {{yes2|yes, via DCC CHAT}}

| {{dunno}}

!IRC

| Savoir-faire Linux Inc.

| 2002 August

| {{free|Open Standard}}

| 40-digit address

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{partial|Medium}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{dunno}}

!Jami (based on DHT and SIP)

| Matrix.org

| 2014 Sep{{cite conference|last1=Ermoshina |first1=Ksenia |last2=Musiani |first2=Francesca |last3=Halpin |first3=Harry|editor=Bagnoli, Franco|display-editors=etal|pages=244–254 |title=End-to-End Encrypted Messaging Protocols: An Overview|book-title=Internet Science |publisher=Springer |location=Florence, Italy |conference=INSCI 2016 |doi=10.1007/978-3-319-45982-0_22 |isbn=978-3-319-45982-0 |date=September 2016 }}{{Failed verification|date=July 2020|reason=p. 247: 'Matrix.org, released in December 2014'}}

| {{free|Open standard}}

| @Username:Hostname (MXID)

| {{Yes}}

| {{Included|Yes, mandatory}}

| {{Yes|Yes, default for private conversations{{Cite web|title=Cross-signing and End-to-end Encryption by Default is HERE

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}} (using pluggable server-side filtering modules and contact ignoring)

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{dunno}}

!Matrix

| Mattermost Inc

| 2015 October 2

| {{free|Open standard}}

|

|

|

|

|

|

|

|

|

|

|

|

|

|

| {{dunno}}

!

| Microsoft

| 1999 Jul

| {{Proprietary}}

| Email address (Microsoft account)

| {{Yes}}

| {{No}}

| {{No}}

| Only for certified robots

| {{No}}

| {{No|Centralistic}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{dunno}}

!MSNP (Windows Live Messenger, etc.)

| Thorvald Natvig

| 1999 Jul

| {{free|Open standard}}

| Username

| {{Yes}}

| {{Yes}}

| {{No}}

| Only for certified robots

| {{No}}

| {{No|Centralistic}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{No}}

| {{No}}

| {{dunno}}

!Mumble

| LY Corporation

| 2011 June 23

| {{Proprietary}}

| LINE ID, Phone Number

|

|

|

|

|

|

|

|

|

|

|

|

|

| {{dunno}}

!

| AOL

| 1997

| {{Proprietary}} (Discontinued 15-Dec-2017){{cite web |url=https://aimemories.tumblr.com/post/166091776077/aimemories |title = AOL INSTANT MESSENGER (AIM) — One Last Away Message}}

| Username, Email Address or UIN
e.g. 12345678

| {{Yes}}

| {{Yes}} (Aim Pro, Aim Lite)

| {{No}}

| {{No}}

| {{No}}

| {{No|Centralistic}}

| {{No|client-based}}

| {{Yes}} (Multiple, simultaneous)

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{dunno}}

!OSCAR (AIM, ICQ)

| Microsoft

| 1997 Mar

| {{Proprietary}} (Discontinued)

| Windows Active Directory Login

| {{No}}

| {{No}}

| {{dunno}}

| {{No}}

| {{No|Centralistic}}

| {{No}}ne

| {{No}}

| {{dunno}}

| {{dunno}}

| {{No}}

| {{No}}

| {{No}}

|

| {{dunno}}

!RVP (Windows Messenger, etc.)

| Invisible.im

| 2014 Mar

| {{free|Open standard}}

| Tor onion address

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{dunno}}

!Ricochet

| Serval Project

| 2016

| {{free|Open Standard}}

| Digit address

| {{Yes}}

| {{No}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{dunno}}

!Serval Project

|Signal Foundation

| 2014 Feb{{cite web|last1=Marlinspike|first1=Moxie|title=The New TextSecure: Privacy Beyond SMS|url=https://whispersystems.org/blog/the-new-textsecure/|publisher=Open Whisper Systems|access-date=12 December 2015|date=24 February 2014}}

|{{free|Open standard}}

|Phone number (e.g. +15550123)

|{{yes}}

|{{yes}}

|{{yes}}

|{{yes}}

|{{dunno}}

|{{yes}}

|{{yes}}, contact blocking

|{{yes}}

|{{yes}}

|{{yes}}

|{{yes}}

|{{yes}}

|{{no}}

| {{dunno}}

!Signal Protocol

| Evgeny Poberezkin

| 2020

| {{free|AGPLv3}}

| No user identifiers

|

| {{Yes}}

| {{Yes}}

| {{Yes}}

|

|

| {{Yes}}

| {{Yes}}

| {{Yes}}, through WebRTC{{Cite web |date=Mar 28, 2023 |title=SimpleX Chat v4.6 – with hidden profiles, community moderation, improved audio/video calls and reduced battery usage. |url=https://simplex.chat/blog/20230328-simplex-chat-v4-6-hidden-profiles.html |access-date=2023-05-09 |website=simplex.chat |language=en}}

| {{Yes}}, through WebRTC

| {{Yes}}

|

|{{no}}

| {{dunno}}

!SimpleX Messaging Protocol

| IETF

| 1996

| {{free|Open standard}}

| user@hostname

| {{Yes}}

| {{Yes}}

| {{Optional}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{partial|Medium}}

| {{dunno}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Depends}} on implementation

| {{dunno}}

!SIP/SIMPLE

| Skype

| 2003 Aug

| {{Proprietary}}

| Username

| {{Yes}}

| {{Proprietary}}

| {{No}}

| {{No}}

| {{No}}

| {{No|Centralistic}}

| {{No|client-based}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{dunno}}

!Skype

| Valve

| 2003 Sep 12

| {{Proprietary}}

| SteamID/Username or Unique Number

| {{Yes}}

| {{Proprietary}}

| {{dunno}}

| {{No|No, although rising}}

| {{Yes}}

| {{dunno}}

| {{No}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{dunno}}

!Steam Friends

|TeamSpeak Systems GmbH

|2001 Aug

|{{Proprietary}}

|Unique ID in base64

| {{No}}

| {{no}}

| {{no}}

| {{dunno}}

| {{dunno}}

| {{dunno}}

| {{dunno}}

| {{yes}}

| {{yes}}

| {{no}}

|

|

|

| {{dunno}}

!

| AOL

| 2005 Sep

| {{Proprietary}} (Discontinued)

| Username or UIN
e.g. 12345678

| {{Yes}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{No|Centralistic}}

| {{No}}

| paying members only

| {{dunno}}

| {{dunno}}

| {{partial}}

| {{dunno}}

| {{No}}

| {{dunno}}

!TOC2

|Threema GmbH

|2012 December

| {{free|Open standard}}

|

|

|

|

|

|

|

|

|

|

|

|

|

|

| {{dunno}}

!

| irungentoo (GitHub user)

| 2013 June

| {{free|GNU General Public License}} (GPL) version 3 or later

| Public & Private key

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}{{Cite web|title=Groups : Chat, call, and share video and files with the whole gang in Tox's group chats.|url=https://tox.chat/|website=tox.chat|language=en|access-date=2021-06-18}}Presence information is indicated to other users by a small coloured dot.{{Cite web|title=Tox clients|url=https://tox.chat/clients.html|website=tox.chat|language=en|access-date=2021-06-18}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}{{Cite web|title=File sharing : Trade files, with no artificial limits or caps.|url=https://tox.chat/|website=tox.chat|language=en|access-date=2021-06-18}}

| {{Yes}}

| {{dunno}}

!TOX (based on DHT)

| Tuenti

| 2006

| {{Proprietary}}

| Username

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{dunno}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{dunno}}

| {{No}}

| {{dunno}}

!Tuenti

| Tencent

| 2011

| {{Proprietary}}

| Username

| Yes

| Yes

| No

| Yes

| Yes

| Yes

| No

| Yes

| Yes

| Yes

| No

| No

| No

| {{dunno}}

!WeChat

| Microsoft

| 1990

| {{Proprietary}} (Discontinued)

| NetBIOS

| {{Yes}}

| {{No}}

| {{No}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{dunno}}

!Windows Messenger service

| Jeremie Miller, standardized via IETF

| 1999 Jan

| {{free|Open standard}}

| Jabber ID (JID)
e.g. usr@a.b.c/home{{efn|name=fn_2}}

| {{Yes}}{{cite web |title=XEP-0313: Message Archive Management |url=https://xmpp.org/extensions/xep-0313.html}}{{cite web |title=XEP-0184: Message Delivery Receipts |url=https://xmpp.org/extensions/xep-0184.html}}

| {{Yes}}{{cite web|title=XEP-0368: SRV records for XMPP over TLS|date=20 August 2019 |url=https://xmpp.org/extensions/xep-0368.html}}

| {{Optional}}{{cite web |title=XEP-0420: Stanza Content Encryption |url=https://xmpp.org/extensions/xep-0420.html}}{{cite web|title=XEP-0027: Current Jabber OpenPGP Usage|url=https://xmpp.org/extensions/xep-0027.html|website=xmpp.org|access-date=2020-03-09|date=2014-03-14}}{{cite web|title=XEP-0373: OpenPGP for XMPP|url=https://xmpp.org/extensions/xep-0373.html|website=xmpp.org|access-date=2020-03-09|date=2018-07-30}}{{cite web|title=XEP-0384: OMEMO Encryption|url=https://xmpp.org/extensions/xep-0384.html|website=xmpp.org|access-date=2020-03-09|date=2018-07-31}}

| {{Yes}}

| {{Yes}}.eg route.all-resource in OpenFire

| {{Yes}}{{cite web|title=XEP-0045: Multi-User Chat|url=https://xmpp.org/extensions/xep-0045.html|website=xmpp.org|access-date=2020-03-09|date=2019-05-15}}{{cite web|title=XEP-0060: Publish-Subscribe|url=https://xmpp.org/extensions/xep-0060.html|website=xmpp.org|access-date=2020-03-09|date=2019-10-06}}

| {{Yes}}{{cite web|title=Extensible Messaging and Presence Protocol (XMPP): Instant Messaging and Presence|url=https://xmpp.org/rfcs/rfc6121.html#blocking|website=xmpp.org|access-date=2020-03-09|date=March 2011}}{{cite web|title=XEP-0159: Spim-Blocking Control|url=https://xmpp.org/extensions/xep-0159.html|website=xmpp.org|access-date=2020-03-09|date=2006-07-11}}{{cite web|title=XEP-0161: Abuse Reporting|url=https://xmpp.org/extensions/xep-0161.html|website=xmpp.org|access-date=2020-03-09|date=2007-05-06}}

| {{Yes}}

| {{Yes|Yes, via Jingle}}

| {{Yes|Yes, via Jingle}}

| {{Yes}}{{cite web |title=XEP-0363: HTTP File Upload |url=https://xmpp.org/extensions/xep-0363.html}}

| {{yes}}{{cite web|title=XEP-0280: Message Carbons|url=https://xmpp.org/extensions/xep-0280.html|website=xmpp.org|access-date=13 December 2018|date=2017-02-16}}

| {{Optional}}{{cite web|title=XEP-0174: Serverless Messaging|url=https://xmpp.org/extensions/xep-0174.html|website=xmpp.org|access-date=1 November 2017|date=26 November 2008}}

| {{yes}}{{cite web |title=XEP-0231: Bits of Binary |url=https://xmpp.org/extensions/xep-0231.html}}

!XMPP

| Yahoo!

| 1998, March 9

| {{Proprietary}}

| Username

| {{Yes}}

| {{No}}{{Update inline|reason=YMSG probably uses TLS based on EFF scorecard from November 2014: https://www.eff.org/node/82654 |?=yes|date=July 2016}}

| {{No}}

| {{No}}

| {{Yes}}

| {{No|Centralistic}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{No}}

| {{dunno}}

!YMSG (Yahoo! Messenger)

| MIT

| 1987

| {{free|Open standard}}

| Kerberos principal
e.g. user@ATHENA.MIT.EDU

| {{Yes}}

| {{No}}

| {{No}}

| {{Yes}}

| {{Yes}}

| {{Yes}}

| {{No}}

| {{Yes}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{No}}

| {{dunno}}

!Zephyr Notification Service

!Creator

!First public release date

!License

!Identity (not inc. alias)

!Asynchronous message relaying

!Transport Layer Security

!End-to-end encryption

!Unlimited number of contacts

!Bulletins to all contacts

!One-to-many routing{{efn|name=fn_4}}

!Spam protection

!Group, channel or conference support

!Audio/VoIP support

!Webcam/Video

!Batch file sharing

!Media synchronization

!Serverless{{efn|name=fn_6}} (decentralized)

!Binary format

!Protocol