Transmission and Multiplexing (TM) - Synchronous Digital Hierarchy (SDH) - SDH leased lines; Connection characteristics (Endorsement of the English version EN 301164 V 1.1.1 (1999-05) as German standard)
传输和多路复用(TM)-同步数字体系(SDH)-SDH租用线路;连接特性(认可英文版EN 301164 V 1.1.1(1999-05)为德国标准)