DIN EN 300420:2002-01
接入和终端 (AT) - 2048 kbit/s 数字结构化租用线路 (D2048S) - 终端设备接口
Access and Terminals (AT) - 2048 kbit/s digital structured leased lines (D2048S) - Terminal equipment interface (Endorsement of the English version EN 300420 V 1.2.1 (2001-07) as German Standard) / Note: DIN ETS standards collection*Endorsement notice