A Digital Subscriber Line Modem is used
to provide high data rates over standard telephone twisted pair
cables. A Digital Subscriber Line Modem supports one or more of
the DSL standards:
ADSL (asymmetric digital subscriber line)
SDSL (symmetric digital subscriber
line))
HDSL (high-speed DSL)
VDSL (very high speed DSL)
A Digital Subscriber Line Modem
may be an asymmetric modem or a symmetric modem, depending
on the type of DSL.
The transmission speed depends on the
length, quality and wire gauge of the copper pair.