You are reviewing basic networking with a coworker and are d

You are reviewing basic networking with a coworker and are discussing the specifications of Digital Subscriber Line, or DSL. You know that the DSL service shares existing copper telephone wire with voice transmission. How is this accomplished?

A. Computers use a phone modem in a NIC to filter out the voice component and pick up the network communication.

B. The phone line is split into two bands, with voice using frequencies below 4000 Hz and DSL using everything above.

C. DSL uses Code Division Multiple Access (CDMA) to isolate network communication from voice communication.

D. Voice uses 64 Kbps on the phone line while DSL uses 128 Kbps on the phone line, splitting the use of the copper wire into two bands.

Solution

B. The phone line is split into two bands, with voice using frequencies below 4000 Hz and DSL using everything above.

Voice and DSL essentially share the same copper wire, each using its own frequency range, with voice using everything below 4000 Hz and DSL using everything else.