Starting with 27C3 the GSM handset registration is managed as self-service. Just follow this simple two-step process:

1. Register a new extension with phone type “GSM”. Give the system a couple of minutes to synchronise with our in-house GSM provider. Relax. Maybe have a nip of your favorite caffeinated beverage, then proceed to step 2.
2. Dial the GSM token shown in the details view of your extension. This step completes the registration process and pairs your device/SIM with the event's GSM network. If you ever feel like switching devices or SIM cards, then just redial this number on your new device.

Of course, the registration can only succeed when operating within the correct GSM network, so please make sure your network provider has been selected accordingly before dialing any number. Selecting a network named 27C3 or some binary digits is probably not the worst choice.

Log in to eventphone, then go to My Extensions and click on the key symbol next to a registered GSM extension.

Please be aware, that your device may be monitored by fellow hackers for quality assurance and your own protection.