Extendible Messaging and Prescence Protocol is based on Xml and is open source and is used in the real time instant messaging and prescence information. Now it is usually a platform on which third party applications like Gtalk, Pidgin and other open source IM clients are based. XMPP as a protocol has gained wide acceptance and can be seen from the popularity it enjoys. It nowadays find itself being extended with the introduction of voice over internet protocol and file transfer signaling. the most desirable aspect of XMPP is that it is open source and modifications and improvement of the software is possible. Like email any one can install the jabber server and run it to talk to other clients. The XMPP standards foundation is responsible for improving the standards and extending the capabilities of the XMPP protocol by developing extensions. The XMPP is decentralized which meas anyone can run a jabber server. So unlike AOL and MSN which contains a centralized server Gtalk doesn’t have one. Every user on the network has a unique Jabber ID (usually abbreviated as JID).The JID is structured like an email address which bypasses the need for a central server and also includes a DNS address for the server user resides separated by an at sign (@), such as email@example.com.