最近这几年,因特网电话技术取得了很大的进展。不仅在电话传输方面效率高、费用低,而且由于与电话网、多媒体技术的结合,开拓出多种多样的新业务。例如: In recent years, great progress has been made in Internet telephony. It is not only efficient and low cost in telephone transmission, but also opens up a wide variety of new services due to its combination with telephone network and multimedia technology. E.g: