This chapter describes the basics of developing WebRTC media web applications. You will learn how to build a simple peer-to-peer video conference with a web chat that will work through NAT and firewalls (in most cases).

The video conference developed in this chapter consists of two applications: the client-side application and the server-side application.

The client code is written in JavaScript and will be executed in the customer's web browser. This application uses the WebRTC API, handles all the media features, and provides a web page.

The server code will be executed on a server (it can even be your work machine). We need the server application to make our conference work well with peers behind NAT (peers who use private IP addresses). The server code is written in Erlang, and you will also get a brief introduction to this language.

As a bonus, you will get basic knowledge of Session Traversal Utilities for NAT (STUN) and Traversal Using Relay NAT (TURN) servers. We will discuss them in a more detailed way in Chapter 4, Security and Authentication.