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世界上第一部电话机诞生于1868年,至今已有近130年的历史。但通讯技术发展最快的时期是近十几年。70年代以前的通讯时代称之为模拟电话时代,80年代为数据通讯时代,90年代则被称为综合信息通讯时代,各种专业业务网络(公用电话网、用户电报网、传真网、数据网等)在实现了用户线路数据化之后,可集成到一个通用的综合业务数据网(ISDN)。综合业务数据网在80年代开始迅速发展,90年代发达国家广泛应用,并逐步向宽带(B-ISDN)发展。90年代的新型信息通讯服务的应用及其影响主要有以下几个方面。
The world’s first telephone was born in 1868, has been nearly 130 years of history. However, the fastest growing period of communication technology is in the last decade or so. The era of communications before the 1970s was called the era of analog phones. In the 1980s, it was the era of data communications. In the 1990s, it was called the era of integrated information and communications. Various specialized business networks (public telephone networks, telegraph networks, fax networks, data networks Etc.) can be integrated into a universal Integrated Services Digital Network (ISDN) after the subscriber line is digitized. The integrated service data network began to develop rapidly in the 1980s and was widely used in the developed countries in the 1990s and gradually developed into the broadband (B-ISDN). The application and impact of new information and communication services in the 1990s mainly include the following aspects.