Business TeleCommunications (BTC) - Open Network Provision (ONP) technical requirements; 2048 kbit/s digital unstructured leased line (D2048U) - Terminal equipment interface; English version ETS 300248:1993/A1:1995
Customer premises cabling for information technology - Part 2: 2048 kbit/s ISDN primary access and leased line network interface; German version EN 50098-2:1996— 15 стр.
Access and Terminals (AT) - 2048 kbit/s digital unstructured leased line (D2048U) - Terminal equipment interface (Endorsement of the English version EN 300248 V 1.2.1 (2001-07) as German Standard)— 1 стр.