gital conversion, 56 kbps can be achieved. [http://www.multitech.com/WHpaper/56Kmodem.htp]
             Figure 6. COMPUTER/MODEM/DIGITAL SERVICE PROVIDER. When there is only one analog to digital conversion in the transmission, 56 kbps is achievable.
             Modem costs for 28.8 or 33.6 kbps are typically under $200. The newer 56 kbps modems generally cost about $200-$300. Coupled with existing telephone lines, modem technology is a very cost effective telecommunications solution.
             Integrated Services Digital Network (ISDN)
             With ISDN, a customer's analog telephone line is replaced by two 64 kbps digital lines. This translates into a total capacity of 128 kbps for ISDN services. Furthermore, the digital implementation requires the installation of special digital telephones. Unfortunately, this ma
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