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前不久,中国电信在上海、北京等城市开通了IP电话业务试验网,这标志着用户打长途电话又有了新的选择。什么是IP电话呢?IP电话又称网络电话,是利用因特网传送数字信号,实现通话的一种先进的通话方式。具体点说就是利用网络软件和网络服务器,将语音转换成数字信号,送到因特网上传输,再通过网络服务器转到对方本地电话网接通被叫电话。因为在因特网中数字传输最常用的标准为IP(Internet Protocol)协议,故国内称之为IP电话。 IP电话从发展阶段和类型上分,大致可分为三类:1995年左右是“计算机对计算机”,1996年后出现“计算机对电话”,现在
Not long ago, China Telecom opened IP telephony pilot networks in Shanghai, Beijing and other cities, marking a new choice for users to make long-distance calls. What is an IP phone? IP phone, also known as Internet phone, is the use of the Internet to send digital signals, call an advanced call. The specific point is the use of network software and network servers, the voice into digital signals, sent to the Internet transmission, and then through the network server to the other local telephone network to connect the called phone. Because in the Internet digital transmission is the most commonly used standard IP (Internet Protocol) protocol, it is called IP telephony in the country. IP phones from the stage of development and the type of points can be divided into three categories: about 1995 is the “computer on the computer”, after 1996, “computer on the phone”, now