00408nam a22001097a 4500020002100000082001700021100002100038245004600059260003900105300003500144650011900179  a817758961X (pbk)  a621.382bDOD  aDodd, Annabel Z.  aThe essential guide to telecommunications  aNew DelhibPearson Educationc2005  axxii, 594 p.b: ill.c; 24 cm.  aDigital communicationaTelecommunicationsvCircuit switched PBXsvPublic networksvSignalingvVPNsvCable TVvFEAS