• Q: I can't find the network with my phone.
    A: The network will be displayed as D23 or DEU23 or 262 23 on your phone.
    If you still have problems finding this network, try it with a different phone.
    Very few phones will not display the network at all.
  • Q: Do I have to pay for the service (Is it free)?
    A: No, you don't have to pay anything. It is totally free of charge.
  • Q: What numbers can I call?
    A: You can call on the following networks:
    - German land line telephony network
    - Mobile telephony networks: Vodafone, T-Mobile, O2, E-Plus
    - University internal telephones
    - RZ-GSM internal
  • Q: Where can I use the network?
    A: You should be able to receive a signal at the following locations/buildings:
    - Computation Department (Rechenzentrum) Hermann-Herder-Str. 10
    - Faculty of Engineering (Technische Fakultät). At the moment we have two BTS installed at the Faculty.
  • Q: Can I receive calls?
    A: Yes, you can receive calls. You have a 3-digit number assigned to you during registration.
    If you don't remember the number, see the question "What is my telephone number?"
    Your complete telephone number is 07612034661XXX (where XXX is your 3-digit number).
  • Q: What number do I need to call to connect to someone?
    A: It depends on the destination you are calling:
    - Internal Call (within the GSM Network): Dial the 3-digit number of the person. Example: 201
    - Call to a university telephone: Dial the 4-digit number of the person. Example 4674
    - Call to the land line and mobile telephony networks: Just dial the number: Example 017123456789
    If you expect problems dialing a 3-digit number, you can use the prefix 4661 to make an internal call. Example 4661201
  • Q: What is my telephone number?
    A: There are a few ways to get your number:
    1. If you are logged into the RZ-GSM, dial *#100# on your cell-phone. The number should be displayed for you.
    2. Make an internal call. Your number is displayed for the person you are calling.
    3. Log into the registration website: Your number is listed there.
    Your complete telephone number is 07612034661XXX (where XXX is your 3-digit number).
  • Q: Is it possible to send SMS?
    A: Yes, you can send SMS to other subscribers of the RZ-GSM network.
  • Q: Is GPRS supported?
    A: No. We are planning to support GPRS in the future.
  • Q: What about UMTS?
    A: This is a GSM network. No UMTS here.
  • Q: What happens if I call a number that is not free of charge?
    A: It says "Goodbye" and your call is ended.
  • Q: What data is stored or used for research? Is the speech content of a call recorded?
    A: We are only storing information that is accumulated during call setup.
    For example: called number, time of the call, duration, Was the call answered?, basestation used.
    We do NOT store or record the conversation content of a call.
  • Q: What happens to my phone if I am connected to the network?
    A: Nothing special. It is just like any other network. We do not try to hack your phone.
    If we intend to do special experiments with the subscribers, we will inform you about what we are going to do.
  • Q: What happens to the login data provided to
    A: The login data is transferred encrypted and is verified with the LDAP-Server of the University.
    From the LDAP-Server we receive the validation, first and last name. After this procedure the password
    is discarded and NOT stored in our system. To make it possible to map the activated SIM-Cards to
    a university account, we have to store only the login name provided.
  • Q: Is the communication between mobile phone and basestation encrypted like in a public network?
    A: If you use your own SIM-Card an encryption is not possible because we do not know the key Ki
    on your SIM-Card. We have programmable SIM-Cards with known Ki. These cards can be used for
    encrypted communication. If you would like to use such a card, please contact us.