What is XMPP and why it is important in Unified Communication

To get a complete understand of XMPP, I recommend the book "XMPP: The Definitive Guide".

In short, XMPP is a protocol (like SIP). XMPP was majorly used for presence and Instant Messaging. But it is being expanded to other areas like call signaling control.

XMPP is getting more and more popular in Unified Communication products like CUPS (Cisco Unified Presence), Cisco Quad (SharePoint-like product), Contact Center, etc.

Since it's a direct competitor with SIP, frequently asked questions would be:

• Shall I learn XMPP?
• Will SIP be replaced by XMPP?

For the first question, Yes. You definitely should learn XMPP because

• XMPP was built from ground to support presence and IM
• XMPP is "eXtensible"
• XMPP is being (or has been) adopted by many big vendors like Cisco, Microsoft, Google, etc.

For the 2nd question, it really depends. On call control and telco interfacing, SIP will still dominate for quite a while because the install base and impact of change.

Anyway, you should take an hour or two to understand XMPP so you can understand what it can do (or do better) on different systems.