ADSL modems can create multiple channels to transfer data. For this, ADSL modems divide the available bandwidth of a telephone line in one of two ways - Frequency Division Multiplexing (FDM) and Echo Cancellation. The FDM assigns one band for upstream data and assigns another band for the downstream data. Further, the downstream path gets sub-divided into one or more high-speed channels by time division multiplexing. Similarly, the upstream path also gets multiplexed into corresponding low-speed channels. Echo Cancellation enables the upstream band to overlap the downstream band. These two bands get separated by means of local echo cancellation. Both Frequency Division Multiplexing (FDM) and Echo Cancellation techniques enable ADSL to split off a 4 kHz region for POTS at the DC end of the band. | 
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| There are many advantages ADSL has over cable modems. It is considered to be far less expensive and has a wider range of availability. Unlike cable?s high-speed Internet services, which are only available in high market areas, ADSL is available in places that cable does not offer Internet access. Thus, ADSL might appeal to consumers who prioritize practicality. | 
