tl;dr: we will operate our own cellular network at 36C3. Bring your
mobile phone(s) and C3SIM card(s). Check the Wiki for latest status and device support.

Like previous years at 36C3 the C3GSM team will run a local cellular
network for mobile phones, alongside the
POC’s DECT system and the NOC’s IPv4 and IPv6 systems. As core network
for our cellular network we use the open source projects osmocom (for
2G/3G) and NextEPC (for 4G). There will only be a very limited number of
SIM cards available to buy. However, cards from previous CCC events can
be used, so please don’t forget to bring them.

As always, we had to ask commercial operators for permission to use some
of their parts of the spectrum, which unfortunately has been completely
sold to very few commercial operators.
We got permission to use 5 MHz of the 850 MHz band, which we will use
for 2G/3G and 10 MHz on the 2600 MHz band for 4G (LTE).

That was rather unfortunate news, as we cannot use a 2G or 3G frequency
which is common in Europe. As 850 Mhz is a frequency commonly used in
the US, some of you will not have a phone which can be used for voice
calls as we don’t support voice over LTE yet.

This also means that contrary to our plans (and for a first time since
many years), this year will not see full 2G coverage of the venue, so
that some very old phones may not work in our network at all.

If you have spare old phones, you are willing to donate to the public,
you are encouraged to throw them in our phone dumpster near the GSM
helpdesk. Remember to wipe all your personal data before and attach a
power adapter if not usb-esque.

Looking forward to route your calls and mobile data in Leipzig! For
questions and support visit the GSM helpdesk Also, we would like to hear
your feedback. Even if things don’t work as expected. Maybe especially
then! ;)