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八十年代,在世界通讯事业上发生了重大的革命,一种新型的具有生命力的ISDN网问世了。美国、日本、西欧等一些国家相继研制成功,并投入使用,西德已将ISDN用于市话网中,并向宽带的ISDN网过渡,美国ATT(电话、电报公司),西德SIMENS(西门子公司),日本HITACHI(日立公司)已经生产出世界先进水平的ISDN产品,国内有武汉、郑州、福州等一些城市已从国外引进了ISDN产品,并在市内电话业务中开通使用。
In the 1980s, a major revolution took place in the world communications industry. A new and viable ISDN network was launched. Some countries such as the United States, Japan and Western Europe have been successfully developed and put into use. West Germany has already used ISDN in the local area network and has transitioned to a broadband ISDN network. ATT (telephone and telegraph company), SIMENS (Siemens ), Japan HITACHI (Hitachi) has produced the world’s most advanced ISDN products. Some domestic cities such as Wuhan, Zhengzhou and Fuzhou have already introduced ISDN products from abroad and have started to use them in the city’s telephone service.