Own number announcement
An automated service for checking connections in the telephone network is referred to as own call number announcement ( ERNA for short ). For this purpose, a fixed service number (usually 0800 Freephone ) of a telephone provider is called, which automatically announces the number of the calling connection. The service is intended for service technicians.
purpose
The purpose of the service is to check that an existing phone line has been assigned the correct number. A service technician can also determine whether the right line is being switched to the right location. Unknown lines can be checked with this service and then reported to the switching center. Use with a mobile phone is not possible. The use of telephone systems is only possible to a limited extent. The service for the technical test of telephone lines also works on connections for which the transmission of the telephone number has been blocked.
ERNA in Germany
procedure
After dialing the phone number and entering the password, the ERNA service reports, for example: "The phone number is 1-2-3-4-5-6-7-8; if that went too fast for you, then again right away. .. ". The number is now repeated much more slowly. Then the announcement "Thank you for your call" and the connection is disconnected. The number is announced without the area code .
During the announcement of the number, various (regionally different) additional functions can be selected by entering additional digits. This makes it possible to call back or send a fax, and the service ID used for the call can also be found out. A language test is also possible, i. H. the system records speech for a few seconds and then plays it back. Some of the announcements used by the system are written in a moody way, so when a callback is requested, the announcement "Please hang up now! I'll call you back" occurs. When you call back, you will hear the announcement "Hello! It's me! I hope my callback helped you!". When a fax is requested, the ERNA service says "Please hang up now. I will send you a fax in normal resolution" or "Please hang up now. I will send you a fax in fine resolution".
Service number
Contrary to popular belief that the number is a trade secret of Deutsche Telekom AG, the service number is easy to derive. Like other Deutsche Telekom AG service numbers, the number begins with the digits 0800-330, followed by the letter "ERNA". The number can therefore not be seriously described as a trade secret. To use the service, however, a PIN is required that differs from region to region and must not be passed on to outside parties. This PIN is also changed every 2 months.
Arcor operates a similar ERNA service, which is not protected by a PIN and can only be reached from Arcor connections.
Disconnected lines
The service can also be used to check lines that have been switched off, in particular those that have only been switched to a passive state and are still enabled for free services.
For lines that are not currently assigned to a customer (e.g. after moving out of an apartment), it is sufficient to try to call any number. When the line is switched from the exchange to the flat, one obtains a so-called UFA announcement (UFA = U nbeschalteter F iktiver A onnection). The area code and an ID number of the connection are announced, separated by a hash. If you want to continue using the line as a new tenant of the apartment, a telephone connection can be provided more quickly when this number is communicated, as this identifies the exact port to which the line in the exchange is connected and the telecommunications company only needs to use the new telephone connection within the system must book on this port. In some cases, this eliminates the need for complex switching appointments.
ERNA in Switzerland
In Switzerland, the service phone number is 0800 820 300.