Datex-L DCE¶

Data Communications Equipment (DCE) for CSPDN__Datex-L came in different flavors. It was owned and serviced by the Telco (Deutsche Bundespost).

User interface¶

The user interface could be implemented in

• X.20
• X.20bis
• X.21
• X.21bis

The synchronous X.20/X.21 interfaces were offered at a lower cost (20-30 DM per month less) than the asynchronous X.20bis/X.21bis variants, due to the simpler DCE design for synchronous networks.

Furthermore, the DCE for asynchronous interfaces had to include a keypad to allow the user to manually dial the destination subscriber. Only the synchronous X.21 interface specifies a method how the DTE could dial directly.

Models¶

• Siemens DFG-300 with X.21bis
• Siemens DFG-9600UE-1 with X.21bis
• Siemens DFG-9600UE-2 with X.21

• Siemens Datenanschaltgeraet (DAG)