Thus, a Basic Rate user can have up to 128 Kbps service. The Primary Rate consists of 23 B channels and one 64 Kpbs D channel in the United States or 30 B channels and 1 D channel in Europe. Integrated Services Digital Network in concept is the integration of both analog or voice data together with digital data over the same network. Today, the Internet is a public, cooperative, and self-sustaining facility accessible to hundreds of millions of people worldwide. Physically, the Internet uses a portion of the total resources of the currently existing public telecommunication networks.
Electronic mail is the most widely used application on the Net.
More recently, Internet telephony hardware and software allows real-time voice conversations. Its outstanding feature is hypertext , a method of instant cross-referencing. When you select one of these words or phrases, you will be transferred to the site or page that is relevant to this word or phrase. If you move the pointer over a spot on a Web site and the pointer changes into a hand, this indicates that you can click and be transferred to another site. Using the Web, you have access to millions of pages of information.