Part 1 of Essay
ISDN, which stands for integrated services digital network, is a system of digitizing phone networks which has been in the works for over a decade. This system allows audio, video, and text data to be transmitted simultaneously across the world using end-to-end digital connectivity. The original telephone system used analo ....

Part 2 of Essay
.... limited number of discrete voltage levels. [Hopkins] The modem was certainly a big breakthrough in computer technology. It allowed computers to communicate with each other by converting their digital communications into an analog format to travel through the public phone network. However, there is a limit to the amount of information that a common analog telephone line can hold. Currently, it is about 28.8 kbit/s. [Hopkins] ISDN allows multiple digital channels to be operated simultaneously through the same regul ....