DMS (Data Management) Ltd Communication Products This section contains E1 D&I Multiplexer, X.21, 4x2 Multiplexer and EOW Hotline. 4x2 Mbits Multiplexer. (Data Sheet). Optical E1 Drop & Insert Multiplexer. (Data Sheet). 2nd Generation Ethernet 4x2 Mbits E2_E3 Multiplexer Cross Connect. (Data Sheet). 2nd Generation 4x2 Mbits E2_E3 Multiplexer . (Data Sheet). 2nd Generation Ethernet 16x2 Mbits E3 Multiplexer (Data Sheet). X.21 Multiplexer 64k G703 Aggregate. (Data Sheet). X.21 Multiplexer 64k X.21 Aggregate (Data Sheet). X.21 Multiplexer (Data Sheet). HOME