channel.[7]
The 10BROAD36 broadband variant of Ethernet was standardized by 1985, but
was not commercially successful.[8][9] The DOCSIS standard became available to
consumers in the late 1990s, to provide Internet access to cable television
residential customers. Matters were further confused by the fact that the
10PASS-TS standard for Ethernet ratified in 2008 used DSL technology, and both
cable and DSL modems often have Ethernet connectors on them.
Power lines have also been used for various types of data communication.
Although some systems for remote control are based on narrowband signaling,
modern high-speed systems use broadband signaling to achieve very high data
rates. One example is the ITU-T G.hn standard, which provides a way to create a
local area network up to 1 Gigabit/s (which is considered high-speed as of
2014) using existing home wiring (including power lines, but also phone lines
and coaxial cables).
In video[edit]
"Broadband" in analog video distribution is traditionally used to
refer to systems such as cable television, where the individual channels are
modulated on carriers at fixed frequencies.[10] In this context, baseband is
the term's antonym, referring to a single channel of analog video, typically in
composite form with separate baseband audio.[11] The act of demodulating converts
broadband video to baseband video. Fiber optic allows the signal to be
transmitted farther without being repeated. Cable companies use a hybrid system
using fiber to transmit the signal to neighborhoods and then changes the signal
from light to radio frequency to be transmitted to over coaxial cable to homes.
Doing so reduces the use of having multiple head ends. A head end gathers all
the information from the local cable networks and movie channels and then feeds
the information into the system.
However, "broadband video" in the context of streaming Internet
video has come to mean video files that have bitrates high enough to require
broadband Internet access for viewing.
"Broadband video" is also sometimes used to describe IPTV Video
on demand.[12]
Internet access[edit]
Main article: Internet access § Hardwired broadband access
In the context of Internet access, the term "broadband" is used
loosely to mean "access that is always on and faster than the traditional
dial-up access".[13][14]
A range of more precise definitions of speed have been prescribed at times,
including:
"Greater than the primary rate" (which ranged from about 1.5 to 2
Mbit/s) - CCITT in "broadband service" in 1988.[15]
"Internet access that is always on and faster than the traditional
dial-up access",[13] - US National Broadband Plan of 2009[16]
4 Mb/s down, 1 Mbit/s up - FCC, 2010[17]
25 Mb/s down, 3 Mb/s up - FCC, 2015[17]
Broadband Internet service is now effectively treated or managed as a
public utility by net neutrality rules.[18][19][20][21][22]
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