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近几年来,我国数据通信业务发展很快。在基础网络平台方面,中国公用分组交换网(CHINAPAC)和中国公用数字数据网(CHINADDN)两网的端口总数已达20万个,用户数超过7万户,可为用户提供的接口速率从1.2Kb/s到2Mb/s,另外还开通了电子邮件Email、传真存储转发、电子数据交换(EDI)、可视图文、在线信息服务等增值业务,基本上满足了现阶段信息通信对基础网络平台的需求。与此同时,随着宽带通信技术和多媒体技术的发展,邮电部门从1995年起,开始在原有CHINAPAC和CHINADDN的基础上,进行宽带数据业务网试验,目前已经在北京、上海、广州等八个城市安装宽带数
In recent years, China’s data communications business has developed rapidly. As for the basic network platform, the total number of ports of CHINAPAC and CHINADDN in China has reached 200,000 and the number of users exceeds 70,000. The interface rate that can be provided to users ranges from 1.2 Kb / s to 2Mb / s, in addition to e-mail, fax storage and forwarding, electronic data interchange (EDI), visual graphics, online information services and other value-added services, basically meet the current information and communication infrastructure Platform needs. At the same time, with the development of broadband communication technology and multimedia technology, the postal and telecommunications department started the trial of broadband data service network on the basis of the original CHINAPAC and CHINADDN since 1995, and has now been tested in Beijing, Shanghai and Guangzhou City installed broadband number