XMPP/Jabber: Messaging Service

The Extensible Messaging and Presence Protocol (XMPP), more commonly known as Jabber, is a flexible approach for asynchronous communications. While chat is the most well-known application of Jabber, Jabber's open specification and extensible message format make it a good choice for a variety of communication and system integration tasks.

These are our software recommendations for Jabber:

• Openfire: for a solid open source Jabber server
• Pidgin: for open source Jabber client program
• PyXMPP or xmpppy: for open source Python client library

One of the great things about Jabber is that there are tons of libraries in all the popular languages to connect to Jabber servers. You can easily have multiple computers using different technologies talk to one another asynchronously using Jabber.