Jabber

Official logo of the Jabber Software Foundation

Jabber is a collection of open, XML-based protocols for instant messaging and presence information. Jabber-based software is deployed on thousands of servers across the Internet and is used by over ten million people worldwide, according to the Jabber Software Foundation [1].

Unlike most instant messaging protocols, Jabber is an open standard. As with e-mail, an account on any Jabber server can communicate with users on other Jabber servers.

History

Jeremie Miller began the project in 1998; its first major public release occurred in May 2000. The project's main product was jabberd, a Jabber server.

The basis of the Jabber protocol, now managed by the Jabber Software Foundation, has been accepted by the IETF in October 2004 as a standards-track protocol under the name XMPP, with RFC 3920. It has often been regarded as being in competition with SIMPLE, based on the SIP protocol, as the standard protocol for instant messaging and presence notification; however, the design of XMPP is intended to provide a more general-purpose XML-based inter-application middleware facility.

In 2005, about half a dozen XMPP server software implementations written in different programming languages and targeting different use cases exist.

In August 2005 Google introduced Google Talk, a combination VoIP and IM system which uses Jabber/XMPP for its instant messaging function. The initial launch did not include server-to-server communications, but as of January 17, 2006, it has server-to-server communications enabled.

Features

Decentralized : The architecture of the Jabber network is similar to email; anyone can run their own Jabber server and there is no central master server. Open Standard : The Internet Engineering Task Force has formalized Jabber's core XML streaming protocols as an approved instant messaging and presence technology under the name of XMPP, and the XMPP specifications have been published as RFC 3920 and RFC 3921. No royalties are required to implement support of these specifications and their development is not tied to a single vendor.; Proven : Jabber technologies have been in use since 1998. Multiple implementations of Jabber's standards exist for clients, servers, components, and code libraries, with the backing of large companies such as Sun Microsystems and Google.Secure : Jabber servers may be isolated from the public Jabber network (e.g., on a company intranet), and robust security using SASL and TLS has been built into the core XMPP specifications.; Flexible : Custom functionality can be built on top of Jabber's core protocols; to maintain interoperability, common extensions are managed by the Jabber Software Foundation. Jabber applications beyond IM include network management, content syndication, collaboration tools, file sharing, gaming, and remote systems monitoring.

How it works

The Jabber network is server-based (i.e. clients do not talk directly to one another) but decentralized; there is no central authoritative server, as there is with services such as AOL Instant Messenger or MSN Messenger. Some confusion often arises on this point as there is, in fact, a public Jabber server being run at "Jabber.org", to which a large number of users subscribe. However, anyone may run their own Jabber server on their own domain.

A user is identified with a user name and a server name. The two fields are separated by the @ sign. This identifier is called a Jabber ID or JID.

Suppose juliet@capulet.com wants to chat with romeo@montague.net. Juliet and Romeo each respectively have accounts on the Capulet.com and Montague.net servers. When Juliet types in and sends her message, a sequence of events is set in action:# Juliet's Jabber client sends her message to the Capulet.com Jabber server#* If Montague.net is blocked on Capulet.com the message is dropped.# The Capulet.com Jabber server opens a connection to the Montague.net Jabber server.# The Montague.net Jabber server delivers the message to Romeo#* If Capulet.com is blocked on Montague.net, the message is dropped.#* If Romeo is not currently connected, the message is stored for later delivery.

Juliet