Vote lock
As Wahlsperre generally in the will Germany prescribed software apparatus, a dial line modem designated, causing after a certain number of unsuccessful call attempts further selection of telephone numbers is inhibited.
history
Until the mid- 1980s , it was forbidden to operate modems that were not owned by Post in Germany . With the liberalization of the telephone market and the proliferation of modems in the 1990 years, from the Federal Office for Telecommunications Approvals (BZT), the later Federal Office of Posts and Telecommunications in order overloading the prescribed (BAPT) the installation of a call bar, telephone network to avoid. Strictly speaking, this regulation applies not only to modems but also to all other end devices that have an automatic dialing function.
function
If, with automatic dialing, the dialing attempts are made less than 30 seconds apart from the next dialing attempt, the dialing lock comes into effect after the 12th dialing attempt and the user is shown the error message "DIAL LOCKED" or "NO DIALTONE". This is only deactivated again if no dialing attempt is made for 120 minutes or if a "manual intervention" takes place (e.g. by switching off and restarting the modem or by entering a special command ).
In most manufacturers' devices, the dial lock can be deactivated or bypassed using a special command from the so-called AT command set . However, since these commands manipulate the functionality of the modem, strictly speaking, when the command is entered, they lose the BZT approval and operation on the German telephone network becomes illegal. For this reason, the commands were not officially announced by the manufacturers and not printed in the operating instructions . However, they were mostly published in specialist journals or online forums .
Current state
From today's perspective, the election block can be seen as a curiosity in the history of telecommunications . With the digitization of the telephone network and the increasing spread of broadband connections ( DSL ), the use of dial-up line modems fell sharply and dialing blocks were no longer necessary.
Other meaning
Another form of dial lock is also available in many cell phones and landline phones to protect them from unauthorized use. It is used to block certain phone numbers or area codes , for. B. to prevent the selection of expensive 0900 numbers or only to allow the selection of emergency numbers. For landline telephones that do not have this function, there are also ballasts - so-called "dial blockers" - which can be connected between the telephone and the telephone connection.
literature
- Peter Winkler: PC-Lexikon 2005. Markt + Technik Verlag, Munich 2005, ISBN 3-8272-6783-8 .
- Helmut Kropp: Contributions to telecommunications. Norderstedt 2015, ISBN 978-3-7347-7884-1 .
- Jörg Fischer, Christian Sailer: VoIP Practical Guide. 2nd revised and expanded edition, Carl Hanser Verlag, Munich 2016, ISBN 978-3-446-44491-1 .
- Werner Bärwald: Expert practice lexicon communication technologies. Networks - Services - Applications. Expert Verlag, Renningen 2009, ISBN 978-3-8169-2843-0 .
- Detlef Jürgen Brauner, Robert Raible-Beste, Martin Weigert: Internet Lexicon. R. Oldenbourg Verlag, Munich 1997, ISBN 3-486-24170-2 .