Swiss electricity companies operate their own automatic telephone network which comprises connections between the various energy supply companies. The telephone exchanges belong to the respective plants or are operated by Swisscom on their behalf. The transmission channels are provided by the SDH networks of the respective companies.
The telephone service, which operates via the electricity companies' own transmission network using dial-up connections, is known as the «EC dial-up telephone service». In some places, the EC dial-up telephone service also provides gateways to EC telephone service networks in neighbouring countries.