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设想一下,在炎热的夏夜打开电视,节目主持人不是在宣讲新的电话特惠计划,而是宣布长途电话全部免费,可以与全球任何一个人聊天,不用付钱,愿意多长时间就多长时间。如果愿意,还可以看见对方的样子。是不是听起来有点太美好、不真实? 其实这正是Internet电话为我们描述的未来美好前景。这种令人吃惊的发明似乎是许多厂商一夜之间生产出来的,实际上他们的老祖宗可以追溯到数字史前的模拟视频电话。AT&T公司曾经大肆鼓吹过一段世界上第一套视频会议系统,那是在1964年,是第一套专为普通电话线路设计的单元。从这些粗糙的原形开始,视频电话的发展一直很缓慢,而且成为昂贵且专有的点对点解决方案。34年以后,两项技术进步真正把免费视频电话变为现实:Internet成为了日常必备,缓慢发展
Imagine turning on the TV on a hot summer’s night. Instead of preaching a new phone offer, the presenter announces that all long distance calls are free, chatting with anyone in the world without having to pay, and how long to wait time. If you like, you can see each other’s appearance. Is not that it sounds a bit too good, not true? In fact, this is the bright future of the Internet phone for us to describe. This surprising invention seems to have been produced overnight by many vendors, in fact their ancestors date back to digital prehistoric analog videophones. AT & T has been a big fan of some of the world’s first video conferencing systems, and in 1964 it was the first cell designed for regular phone lines. From these crude prototypes, videophones have been slow to develop and become costly and proprietary peer-to-peer solutions. After 34 years, two technological advances have really made the free video phone a reality: the Internet has become a daily necessity and a slow development