In the case of a direct call, the destination address or the call number is not transmitted to the exchange by the caller, but is permanently stored in the access node. In networks for private mobile radio and trunked radio, direct calls can be made in half- duplex or full-duplex mode. Direct call is also available as a feature of private branch exchanges, telephones or cell phones. It involves the automatic establishment of a connection to a stored call number, with the direct call being triggered by pressing a key. This makes this feature suitable for people in need of help or for children.