Replacing 'ring ring' with the Jurassic Park theme song using a PBX

Today I learnt something new. The ‘ring ring’ you hear when you make a phone call isn’t generated by your phone, your network or even the country you’re in, that noise is generated by the receiving ends phone system, and this means it can be customized.

I was trying to find a way of recording all my phone calls. On an iPhone this isn’t very easy due to privacy standards. There are lots of apps that offer to record your calls but they only work if your carrier supports 3-way call merging which mine does not.

The more I learn about phone systems I realise they are very much like email; ancient, insecure by default and easily manipulated, caller ID spoofing is very easy to do.

What happens when somebody calls me?

How is this achieved?

These steps summarise the method. I encourage you to download and setup your own PBX it’s a great skill to have on any CV.

  1. Find yourself a SIP VOIP telephone service provider or trunk provider, I use sipgate basic because they offer a basic package for free. You’ll want to make note of your SIP ID and password, this is different to the credentials you use to register for the service.

  2. Deploy an instance of FreePBX. “FreePBX is a web-based open source GUI that controls and manages Asterisk (PBX), an open source communication server.” Boot from the ISO and there is an automated installer, you now have yourself a fully fledged phone system. Follow their getting started guide to configure your PBX with your phone provider from step 1, setup your first extension, inbound route and upload the music as hold music.

  3. Enable Find Me/Follow Me for your extension and enable ‘Play Music On Hold’ selecting the song you have uploaded

  4. Forward your personal mobile number to your new SIP numbe

  5. Download and install a SIP client on your phone so you can recieve calls, personally I use Acrobits Softphone.

  6. Eagerly wait for somebody, anybody, to call you.