| Most options for increasing modem speed
from the standard 56K today to megabit rates involve changing the "wire"
- cable, fiber optics, or satellites. But installing fiber optic cable
to the home can cost $1-1.5K for ISDN support. ADSL modems use multiple
channels on the 700 million existing copper phone lines.
One channel is used for the standard phone line, allowing data and voice
to be sent simultaneously. The "A" stands for Asymmetric, referring to
the fact that the downstream channel is much faster than the upstream
channel (you spend more time getting information from the web than sending
it). Maximum rates, depending on distance, are 8 Mbps downstream and 640
kpbs upstream. The telephone company's switching equipment, designed for
short-duration telephone calls, is better used by separating data connections
onto more efficient equipment. DSL modems are available primarily from
the service providers (the telco or ISP). Prices dropped recently to $49/mo
from several suppliers for 384 kbps speeds.
Dataquest expects DSL modems to sell 3.7 million in U.S. in 2000, outselling
cable and ISDN combined. |
DSL
Market Overview