Dial up connections are available anywhere a

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Dial-up connections are available anywhere a telephone line exists. Data transfer rates include 28.8 Kbps, 33.3 Kbps, and 56 Kbps. Dial-up connections cannot be used for both voice (phone calls) and data at the same time. Digital Subscriber Line (DSL) DSL provides broadband digital data transmission over existing telephone lines. DSL divides the telephone line into multiple channels. One channel is used for analog voice, while the remaining channels are used for digital data. Filters are used to separate the analog voice data from digital data. Several DSL standards exist, including ADSL, SDSL, and HDSL (collectively referred to as xDSL ). Depending on the type of DSL used, you can use the same line for simultaneous voice and data. DSL is not available in all areas; the service location must be within a fixed distance of telephone switching equipment. Integrated ISDN is a digital service, running over a switched network.
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Services Digital Network (ISDN) There are two versions of ISDN: o ISDN BRI divides the regular copper telephone line into three channels: 2 64-Kbps bearer (B) channels can transfer data up to 128 Kbps (data compression increases the data transfer rate). Only one B channel is used during phone use reducing maximum speed to 64 Kbps. 1 16-Kbps delta (D) channel for connection control. o ISDN PRI requires different cables to be installed rather than the regular phone lines. The cable is divided into 24 channels: 23 B channels (each at 64 Kbps) for data transmission. 1 D channel (at 64 Kbps) for connection control. ISDN is not available in all areas; subscribers are required to be within a certain proximity of telephone company equipment. ISDN is more common in Europe than in the United States. Cable Cable networking uses a cable TV connection to create a wide area connection to the Internet. A cable modem (router) connects the computer to the cable network for sending networking signals. The same cable line is used to carry networking and cable TV signals, although in some cases a separate line is installed for Internet access. Cable networking requires the installation of a cable TV line to your location if one does not exist. Cellular Cellular networking uses the cellular phone infrastructure for Internet access. Mobile phones with digital data plans use cellular signals to connect to the Internet. Devices can connect to a cellular Internet connection in a variety of ways: o Many smartphones use a technique known as tethering to provide cellular Internet to another device. Tethering typically requires the smartphone to be connected via a USB cable. o A mobile hotspot is a cellular device that provides Internet access by creating a small Wi-Fi network to which multiple devices can connect. Most smartphones have built-in mobile hotspot functionality.
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