Book excerpt: Unleash the power of XMPP in order to build exciting, real-time, federated applications based on open standards in a secure and highly scalable fashion About This Book Learn about the fundamentals of XMPP and be able to work with the core functionality both server-side and in the browser Build a simple 1-to-1 chat (the “Hello World” of XMPP), explore multi-user chat, publish subscribe systems, and work with a decentralized social network Author Lloyd Watkins is a member of the XMPP standards committee Who This Book Is For If you want to learn about the fundamentals of XMPP, be able to work with the core functionality both server-side and in the browser then this book is for you.No knowledge of XMPP is required, or of TCP/IP networking. It's important that you already know how to build applications of some form, and are looking get a better understanding of how to implement XMPP for one or more of its many uses. You should be interested in the decentralized web, know HTML, and likely know JavaScript and NodeJS. You will probably know JSON, and hopefully XML (this is the native output of XMPP). What You Will Learn Install and configure an XMPP server and use it to connect from a traditional desktop client and send a message Build a simple server-side application that will respond to messages from our logged in desktop client Install and run XMPP-FTW, connect to the server from the browser, and handle incoming/outgoing messages Connect to a multi-user chat room, send/receive stanzas, add a room password, join a protected room, set the room's subject, and change a user's affiliation Get to grips with the publish-subscribe extension of XMPP and use it to build a pusher system that can make any website real-time Build a simple XMPP component and create an extension for XMPP-FTW that allows you to use your own custom format Build an XMPP version of the classic game “Pong” In Detail XMPP (eXtensible Messaging and Presence Protocol) is a messaging protocol that enables communication between two or more devices via the Internet. With this book, developers will learn about the fundamentals of XMPP, be able to work with the core functionality both server-side and in the browser, as well as starting to explore several of the protocol extensions. You will not only have a solid grasp of XMPP and how it works, but will also be able to use the protocol to build real-world applications that utilize the power of XMPP. By the end of this book, you will know more about networking applications in general, and have a good understanding of how to extend XMPP, as well as using it in sample applications. Style and approach Through a number of hands-on projects, this book shows you how to build usable applications that highlights a feature of XMPP.