Info.svg Net is currently in running state. 2G+3G Voice as well as 3G+4G Data are operational. Please report if some areas currently have bad coverage. Old phones without AMR codec won't work!

An experimental private 2G/GSM, 3G/UMTS, 4G/LTE network is provided via Osmocom during the Camp.

It is set up by the GSM/MOC (Mobile Operation Center). You can use the GSM network to place calls or send SMSs for free on the GSM and DECT networks.

Data will be provided over 3G and 4G only.

Current data availability (your need to add/setup an APN with access point name "internet"):

    • 2G/GSM: working (voice/SMS only, no data)
    • 3G/UMTS: working (voice, SMS, data)
    • 4G/LTE: working (data only, no voice/SMS)

SIM card, registration

To be able to use the GSM network, you require a SIM card dedicated for the CCC event network.

Any SIM issued at any of the previous CCC events with a GSM network will automatically work. (There could be some problems if your phone you are using now has only 2G, when you used 3G on events before)

If you don't have a SIM from a previous event, you can obtain one from the POC (Phone Operation Center). There is only a limited quantity available, so please only buy a new card if you don't have one from previous events.

After you have obtained a suitable SIM,

  1. Register/log-in on eventphone
  2. Register a new extension with phone type "GSM". Give the system a couple of minutes to synchronize with our in-house GSM provider. Relax. Maybe have a nip of your favorite caffeinated beverage.
  3. 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.

Self Service USSD

  • get your own extension: *#100#
  • query 3G status: *#102#
  • query extension: *#100#
  • 3G on: *#301#
  • 3G off: *#300#

Additional information

  • The ARFCNs used are in the upper part of the 1800MHz DCS frequency band (former DECT guard band)
  • The 3G UARFCN is in the 850 Mhz band.
  • The 4G EARFCN are in the 2600 MHz band (band 7)
  • All frequencies are used under License of the German regulatory authority (BNetzA
  • You can re-use the GSM token you got when creating an extension with any SIM for this network.
  • We are operating at 200mW Output power
  • Currently there are 10 2G and 14 3G cells in use.


  • I can't call with my old phone: some very GSM only candy bar phone (such as the Nokia 3310) do not support the AMR voice coded which we required to operate the 3G network. You can still receive and send SMSs, but won't be able to make calls (until we add support voice transcoding)
  • I can't find the 3G/UMTS network: we operate base station using frequencies in band 5. Verify if your phone support band 5.
  • I would like to try the LTE network: the LTE network is still experimental, thus we used a different "operator name". Do a manual network search in your phone and select network 901 42 (instead of D/262 42). You don't need another SIM card. The LTE network is for data only. Voice and SMS are only supported on 2G/GSM and 3G/UMTS.
  • My phone can't connect to the network, or is not allowed anymore: if you have an old SIM card (black, from 30c3), this can happen when you loose coverage. Reboot the phone to fix the issue.


List of ARFCNs:

  • 680 (1838,8/1743,8 MHz)
  • 683 (1839,4/1744,4 MHz)
  • 686 (1840,0/1745,0 MHz)
  • 689 (1840,6/1745,6 MHz)
  • 692 (1841,2/1746,2 MHz)
  • 695 (1841,8/1746,8 MHz)

List of UARFCNs:

  • 1007 (band V, 871.5/826.5 MHz)

List of EARFCNs:

  • 3175 (Band 7, 2662.5 / 2542.5 MHz)
  • 3225 (Band 7, 2667.5 / 2547.5 MHz)

The GSM and LTE frequencies have been generously provided by Telefonica for this event.

The UMTS frequency is from a band not used in Germany.

Technical Information

If you are interested in technical details you can drop by at the GSM tent next to the POC located in Village:Singularity_City.

sysmoBTS hardware

We use sysmoBTS hardware as actual GSM BTS (Base Transceiver Station). The software on the sysmoBTS is the Free Software program OsmoBTS, developed under the Osmocom umbrella. OsmoBTS implements the GSM protocol layer 2 and interfaces towards the backend, OpenBSC using the A-bis over IP protocol in a dedicated VLAN of the switched Camp ethernet backbone.

The Backend: Osmocom Cellular Network Infrastructure

you can find detailed Information about the software infrastructure in the

you can find detailed Information about the software infrastructure


The LTE network has been described in more details in a separate presentation at the singularity village. You can find the slides here.

The slides describing the overall network operation meant for the infrastructure review are available here.

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