The Telecommunications RevolutionBook 4,Unit 4Text A2Proper namesvtelecommunicationsvopticalfiber(L.6)/high-capacityopticalfiberlinks(L.38)vcable(L.7)vcopperwire(L.8)vdigitalswitches(L.8)/digitalmodel(L.22)/digitalmobilephonesystems(L.51)vwirelesstransmissionsystems(L.9)vtheInformationAge(L.10)vaspiderswebofdigitalandwirelesscommunicationlinks(L.11)v电信v光纤.光学纤维/高容量的光纤电缆网v电缆v铜线（电缆）v数字转换器/数字模式/数字移动电话系统v无线传播系统v信息时代v一个蜘蛛网般的数字和无线通信网络3Proper namesvthe information superhighway(L.39)vlog on(to)/log out/o
