Book Image

Practical XMPP

By : Lloyd Watkin, Steven Watkin, Koelle
Book Image

Practical XMPP

By: Lloyd Watkin, Steven Watkin, Koelle

Overview of this book

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.
Table of Contents (11 chapters)
Free Chapter
1
1. An Introduction to XMPP and Installing Our First Server

Are we there yet?

Pubsub at its core is really a simple concept. There is a store of data to which you subscribe; you can retrieve information from this data store, and when there are updates, you are told about them. While it is a simple concept, it is also a very powerful one because it's hard to think of an application that doesn't use some form of publish/subscribe arrangement, a database for example.

One of the advantages is that once the server receives this stream opener and knows that it is configured for a component on this address it responds to XMPP. Pubsub is that clients that do not need to poll the server for updates (or the "are we there yet?" syndrome) but will get pushed updates when they happen. This property of pubsub makes it ideal for building real-time systems as it reduces the load on the server from polling and ensures that data is received by clients as soon as possible.