普通电话挂长话。由用户端的简单通信终端(电话)通过双绞线接入程控交换机,再由交换机接入长途传输网,传送到对方交换机,再由交换机传送到对方电活。在这个传送过程中,因为要在通活期内,在很远的两地(如跨国)建立一条连通电路,使得通话成本非常高,随着电子、电脑技术的发展,网络电话对上述通信方式做了一些改进、主要有以下几点优势: 语音压缩。普通电话是没有语音压缩的,而网络电话利用用户端的电脑或交换机侧的计算机将 Ordinary phone long-distance calls. The simple communication terminal (telephone) of the user terminal is connected to the program-controlled switch via the twisted pair, then the switch is connected to the long-distance transmission network, transmitted to the other switch, and then transmitted by the switch to the other party. In this transmission process, because of the need to establish a circuit connection between remote areas (such as transnational) during the period of livelihood, so that the call cost is very high. With the development of electronic and computer technologies, Some improvements, the main advantages are the following: voice compression. Ordinary phone is not voice compression, and Internet phone using the client’s computer or the switch side of the computer will