Data circuit-terminating equipment

Each communication system is formed by (at least) two data stations, which are connected by a transmission path (general communication device ).

Components and function

Each data station consists according to DIN 44302 from

• The data terminal equipment (DTE ) (English Data Terminal Equipment - DTE) and
• The data communications equipment (DCE ) (English Data Communication Equipment - DCE).

This division into two units, namely, data terminal equipment and data transmission device, originally dates from the time when the communication networks were still predominantly in the hands of state-owned postal administrations. As a rule, their territorial range was up to the interface (DIN 66020 and DIN 66021 ) between them, which was a private DCE device that had to be hired. DTE uses the waveforms and voltages, which are not suitable for transmission on trunks. It is an object of the DCE to carry out the conversion into signals that are suitable for transmission on trunks. The tasks of the interfaces arise from the respective transmission method. After the abolition of telecommunications monopolies this division of DTE and DCE on different devices was unnecessary. Today DTE and DCE are only functional separations, the functions can, however, be combined in a single device.

The data terminal is a device which

• Send data (data source = origin of the data ) and / or
• Receive data ( data sink = destination of the data)

Can. The DTE provides a standardized interface which may be connected to a data transmission device. A peripheral data terminal is called data terminal or terminal. Typical communication devices are monitors, printers, POS data, ATMs, etc. As a rule, at least one of the communication devices involved at each data transmission system, a computer. Are at least two communication devices computer, there is a computer network.

The data transmission device (for example, modem ) is composed of

• The signal converter and
• The connector unit
• Possibly error control (device dependent)
• Possibly synchronizing unit (device dependent)

The object of the DCE is the adjustment of the output from the data terminal equipment signals to the transmission path. Each of these units can be equipped with a transmitting part and a receiving part. To establish a connection is an automatic selection means are present, this is part of the data transmission device.

The signal converter (English Signal Converter ) brings the delivered from the DTE data signals into a form suitable for the transfer form and / or bringing the data received from the transmission line data signals in the prescribed form for the interface. In circuit-switched dial-up networks DCE can not assume call processing tasks.