Instant Messaging: Protocols are "Commons", Let's Take Them Seriously / ProcessOne
TLDR; Thirty years after the advent of the first instant messaging services, we still haven't reached the stage where instant messaging platforms can freely communicate with each other, as is the case with email. In 1999, the Jabber/XMPP protocol was created and standardized for this purpose by the Internet Engineering Task Force (IETF). Since then,
Source: process-one.net