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我国已建成具有多种先 进手段和多种通信业 务的国家公用电信网。我国公用电信网电话交换机总容量已突破1亿门,成为世界第二大电话网;全国光缆总长度已达82万公
Our country has built up a national public telecommunication network with various advanced means and various communication services. The total capacity of PSTN telephone exchanges in China has exceeded 100 million and has become the second largest telephone network in the world. The total length of national optical fiber cables has reached 820,000