00511nam 2218408 450000100060000000300230000600500090002900800410003808200100007907200250008902000180011410000150013226000420014724500400018965000250022965000490025465000280030318408StarLibrary Marc Built20180430201711 ||||| |||||||||||amh  a004.6 acommunications media a81-85336-33-4 aJohn Freer bAffiliated east-west press pvt c1990 aCOMPUTER COMMUNICATION AND NETWORKS acommunications media adata communication concepts and alternatives amodems and multiplexers