Editing Instant messaging (section)

== Interoperability ==
[[File:Pidgin Screenshot Ubuntu.png|thumb|200px|left|Pidgin's tabbed chat window in Linux]]

Most IM protocols are [[Proprietary protocol|proprietary]] and are not designed to be [[interoperable]] with others, meaning that many IM networks have been incompatible and users have been unable to reach users on other networks.<ref>{{cite web |date=19 April 2023 |title=A Brief History of Chat Services |url=https://sameroom.io/chat-timeline.pdf |publisher=sameroom.io}}</ref> As of 2024, fragmentation of IM services means that a typical user is likely to have to use more networks than ever, including the need to [[download]] the apps and signing up, to stay in touch with all their contacts.<ref>{{Cite web |title=The best all-in-one messaging apps in 2024 |url=https://zapier.com/blog/best-all-in-one-messaging-app/ |access-date=2024-08-06 |website=zapier.com |language=en}}</ref> However, there had been attempts for solutions.<ref name="zdnet"/>

Multi-protocol clients can use any of the IM protocols by using additional local libraries for each protocol. Examples of multi-protocol instant messenger software include [[Pidgin (software)|Pidgin]] and [[Trillian (software)|Trillian]],<ref name="zdnet" /> and more recently [[Beeper (application)|Beeper]]. These third-party clients have often been unable to keep up due to proprietary protocol restrictions and getting locked out of it.<ref name="zdnet" /> For instance, in 2015, [[WhatsApp]] started banning users who were using unofficial clients.<ref>{{Cite web|url=https://news.softpedia.com/news/WhatsApp-Permanently-Bans-Users-of-Unofficial-Clients-475013.shtml|title=WhatsApp Permanently Bans Users of Unofficial Clients}}</ref> Major IM providers usually cite the need for formal agreements, and [[computer security|security]] concerns as reasons for making changes.

=== Attempted open standards ===
There have been several attempts in the past to create a unified standard for instant messaging, including:

* [[IETF]]'s [[Session Initiation Protocol]] (SIP) and [[SIMPLE (instant messaging protocol)|SIP for Instant Messaging and Presence Leveraging Extensions]] (SIMPLE)
* [[Application Exchange]] (APEX),
* [[Instant Messaging and Presence Protocol]] (IMPP),
* [[Extensible Messaging and Presence Protocol]] (XMPP), based on [[XML]], and
* [[Open Mobile Alliance]]'s [[Instant Messaging and Presence Service]] (IMPS), developed specifically for mobile devices.

=== History and agreements ===
{{Quote box
| quote = Critics say AOL's slowness in embracing interoperability has caused setbacks to other companies trying to grow their businesses. AOL has said it supports the development of an interoperable system for all IM networks but has cited privacy and security concerns as the reasons it's taking its time. Competitors have labeled that argument a "smoke screen."
| author = Evan Hansen
| source = [[CNET]], January 2001<ref>{{Cite web|url=https://www.cnet.com/tech/services-and-software/aol-time-warner-complete-merger-with-fcc-blessing/|title=AOL, Time Warner complete merger with FCC blessing|website=CNET}}</ref><ref>{{Cite web|url=https://www.zdnet.com/home-and-office/networking/green-light-for-aol-time-warner-merger/|title=Green light for AOL-Time Warner merger|website=ZDNET}}</ref>
| align = right
| width = 30%
}}
In the early 2000s, when instant messaging was quickly growing, most attempts at producing a unified standard for the-then major IM providers ([[AOL]], [[Yahoo!]], [[Microsoft]]) had failed. There was a "bitter row" between AOL and its rivals regarding the opening up of their networks.<ref>{{Cite news |date=2002-12-19 |title=AOL wins instant messaging case |url=http://news.bbc.co.uk/2/hi/technology/2591723.stm |access-date=2024-08-06 |language=en-GB}}</ref> In 2000, U.S. regulatory [[Federal Communications Commission]] (FCC) proposed, and supported by Microsoft chairman [[Bill Gates]], that AOL providing interoperability of its [[AIM (software)|AIM]] and [[ICQ]] instant messengers with Microsoft's [[MSN Messenger]] was a condition for the forthcoming [[AOL Time Warner|AOL-Time Warner merger]].<ref>{{Cite web |title=Gates Adds His Voice To Instant Messaging |url=https://www.forbes.com/2000/12/20/1220messaging.html |access-date=2024-08-06 |website=Forbes |language=en}}</ref>

However, in 2004, Microsoft, Yahoo! and AOL agreed to a deal in which Microsoft's enterprise IM server [[Live Communications Server 2005]] would have the possibility to talk to their rival counterparts and vice versa.<ref>{{Cite web |last=Hicks |first=Matthew |date=2004-07-15 |title=Microsoft Opens IM Server to AOL, Yahoo |url=https://www.eweek.com/enterprise-apps/microsoft-opens-im-server-to-aol-yahoo/ |access-date=2024-08-06 |website=eWeek |language=en-US}}</ref> On October 13, 2005, Microsoft and Yahoo! announced that their IM networks would soon be interoperable, using SIP/SIMPLE. This was finally rolled out to [[Windows Live Messenger]] and [[Yahoo! Messenger]] users in July 2006.<ref>{{Cite web |title=Microsoft, Yahoo connect IM services |url=https://www.cnet.com/tech/services-and-software/microsoft-yahoo-connect-im-services/ |access-date=2024-08-06 |website=CNET |language=en}}</ref> Additionally, in December 2005 by the AOL and [[Google]] strategic partnership deal, it was announced that AIM and ICQ users would be able to communicate with [[Google Talk]] users.<ref>{{Cite web |last=Bylund |first=Anders |date=2005-12-21 |title=Google buys 5 percent of AOL; Google Talk and AIM to chat it up |url=https://arstechnica.com/uncategorized/2005/12/5814-2/ |access-date=2024-08-06 |website=Ars Technica |language=en-us}}</ref> However this feature took until December 2007 to roll out.<ref>{{Cite web |last=Schwartz |first=Barry |date=2007-12-05 |title=Google Talk Meets AOL Instant Messager: Time Warner & Google Complete AIM Integration Deal |url=https://searchengineland.com/google-talk-meets-aol-instant-messager-time-warner-google-complete-aim-integration-deal-12853 |access-date=2024-08-06 |website=Search Engine Land |language=en}}</ref> [[XMPP]] provided the best example of open protocol interoperability, having had gateways that connected to Google Talk, [[Lotus Sametime]] and others.<ref>{{Cite web |title=Jabber gateway aims to link XMPP, SIMPLE |url=https://www.infoworld.com/article/2206683/jabber-gateway-aims-to-link-xmpp-simple.html |access-date=2024-08-06 |website=InfoWorld |language=en-US}}</ref>

Later, [[Rich Communication Services|RCS]] was developed by telecommunication companies as an instant messaging protocol to replace [[SMS]] under a unified standard. In 2022, the European Union passed the [[Digital Markets Act]], which largely came into effect in early 2023. Among other things, the legislation mandates certain interoperability between the largest IM platforms in use in Europe.<ref>{{Cite web |last=Claburn |first=Thomas |title=EU mandated interoperable messaging not so simple: Paper |url=https://www.theregister.com/2023/03/29/eu_mandated_messaging_interop_paper/ |access-date=2023-11-11 |website=www.theregister.com |language=en}}</ref> As a result, in March 2024, [[Meta Platforms]] opened up its WhatsApp and [[Facebook Messenger|Messenger]] networks to be interoperable.<ref>{{Cite web |last=Jowitt |first=Tom |date=2024-03-13 |title=Meta Messaging Interoperability Whatsapp, Messenger |url=https://www.silicon.co.uk/mobility/mobile-apps/meta-adds-messaging-interoperability-for-whatsapp-messenger-554502 |access-date=2024-08-06 |website=Silicon UK |language=en-GB}}</ref>

=== Technical ===
There are two ways to combine the many disparate protocols:
* Combine the many disparate protocols inside the IM ''[[client (computing)|client application]]''.
* Combine the many disparate protocols inside the IM ''server'' application. This approach moves the task of communicating with the other services to the server. Clients need not know or care about other IM protocols. For example, [[Live Communications Server 2005|LCS 2005]] Public IM Connectivity. This approach is popular in [[XMPP]] servers; however, the so-called transport projects suffer the same [[reverse engineering]] difficulties as any other project involved with closed protocols or formats.

Some approaches allow organizations to deploy their own, private instant messaging network by enabling them to restrict access to the [[Server (computing)|server]] (often with the IM network entirely behind their [[firewall (computing)|firewall]]) and administer user permissions. Other corporate messaging systems allow registered users to also connect from outside the corporation LAN, by using an encrypted, firewall-friendly, HTTPS-based protocol. Usually, a dedicated corporate IM server has several advantages, such as pre-populated contact lists, integrated authentication, and better security and privacy.{{Citation needed|date=August 2024}}