Free Click-to-Call to Your Call Center from the Website: Integrating WebRTC, SIP.js and FreePBX
Introduction Customers can now call the call center straight from the company website, free of charge, with no phone credit and no extra app. They click a Call Us button, allow microphone access in the browser, and the call lands in the agent queue like any ordinary phone call. The technology behind it is WebRTC , which is built into every modern browser. On the browser side we use the SIP.js library, and on the server side we use FreePBX (Asterisk). This article covers the architecture we use, three problems we ran into in practice, and how we solved them: How to tell callers apart when every web visitor shares the same SIP account. How to make the call center system, which only reads the Caller ID, still recognize each caller. How to stop the credentials embedded in the browser from being abused to make free calls anywhere. Topology A call travels from the browser to the WebRTC FreePBX, is forwarded over a trunk to the internal FreePBX, and then enters the call center q...