非对称数字用户线(ADSL)是近两年来崭露头角的一种新的双绞线接入技术。这一技术保留了目前用户接入电话网络的双绞铜线环路的优点。ADSL调制解调器装在环路的两端,实现了大大超过现有电话业务速率的高速连接。由于ADSL利用现有的电话线,所以它象公共电话一样,可在电话 Asymmetric Digital Subscriber Line (ADSL) is a new twisted pair access technology that has emerged in recent two years. This technique retains the benefits of current twisted pair copper loops for users accessing the telephone network. ADSL modems are installed at both ends of the loop, enabling high-speed connections that far exceed the speed of existing telephony services. Since ADSL utilizes existing phone lines, it can be on the phone like a public phone