About Cosmic Cable Ltd.

Comsic Cable is the lost cause of a post-bureaucratic telephone network provider mostly run by a crew of the best rogue technicians.
Founded in 2016 as an alternative to the bad mobile network at Lärz, Germany it provides the most stylish telephone booths at both Fusion Festival and at.tension Festival to connect participants. The telephone network is complemented by additional well-known Cosmic Cable services like the “Status Box” which provides asynchronous communication for guests as well as yearly changing entertainment options.

Technical Setup

Within the Cosmic Cable network everything starts with a classic rotary dial telephone. Since building a whole analogue telephone network is very time consuming we use old Fritz Boxes to adapt the telephones to a TCP/IP based network. From then on the we use all kinds of standard networking gear. On the festival site we often use Ubiquiti Nanostations to establish radio links when no cable links are available. As a software PBX we run a Asterisk setup which implements the service features that Cosmic Cable offers. The configuration is available publicly on Github.
Another important part of attractive telephone booths is the audiovisual ringing which combines the classical ringtone with some other effect like blinking lights or a flamethrower. To trigger such events we have used two different concepts over the years.
First we had selfmade relay or other driver PCBs on the second analogue port on the Fritz Box. The Asterisk server then automatically called the corresponding number on specific events. Later on we developed the so called Mystery Box which has a analogue telephone pass-through and a 12V output which is constantly toggled as long as there’s ringing on the line. The box also provides connection terminals for 12V powered light as well as a passive POE injector to drive the Nanostations.
Although dial phones are awesome, there exist considerably constraints when using them. The most important thing is to adapt them to a digital network in a simple but flexible way. The old Fritz! boxes where cheap and easy to use but configuration is impossible to automate, support for software non existing and most annoying: the moment the dialing is complete you can not dial additional numbers, what prohibits any kind of interactive menus.
We therefor start to use more and more new router boxes which can be flashed with OpenWRT.
During the events we also visualize the ongoing phone calls on a map. See github.com/dronus/asterisk_vis.