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互联网已深入寻常百姓家,黑客与防黑,相信大家早已耳熟能详。那么作为互联网的一种功能扩展,IP电话卡是否也须防黑呢?答案是肯定的。IP电话是Internet Phone的简称,意即互联网电话。IP电话最早应用于两台都装有调制解调器(带语音)的电脑之间的通话,语音信号通过麦克风拾取后,在调制解调器和电脑之间完成采样、量化、打包,最后通过调制解调器将打包的数字信号送到互联网上,传入另一台电脑中进行解包,还原成模拟的语音信号。因为IP电话具有话费便宜和可保密性强等优点,IP电话又扩充到了普通的电话机上。
Internet has penetrated the homes of ordinary people, hackers and anti-black, I believe we have long been familiar. So as a function of the Internet to expand, IP phone cards also need to be anti-black? The answer is yes. IP phone is short for Internet Phone, which means Internet phone. The earliest application of IP phones is to talk between two computers equipped with modems (with voice). After the voice signals are picked up by the microphones, they are sampled, quantified and packaged between the modem and the computer. Finally, the digital signals Sent to the Internet, into another computer unpacking, reduced to analog voice signals. Because IP phones have the advantages of cheap calls and confidentiality, IP phones have been extended to ordinary phones.