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As technology grows, so does our
need for bigger, better and faster. Over the years,
the way content is presented via the web
has changed drastically. Ten years ago being able to
center bold, colored text was something to admire,
while today Flash®, animations,
online gaming, database-driven
websites,
e-commerce
and virtual
offices — to name but a few — are becoming
standards. The need for speed has changed the
options available to consumers and businesses alike
in terms of how and how fast we can connect to the Internet.
While technology changes at a rapid
pace, so do Internet
connections. The connection speeds listed below
represent a snapshot of general average to maximum
speeds at the time of publication (4/8/2006). This
no doubt will change over time and Internet
connection speeds also vary between Internet
Service Providers (ISP).
Analog
(up to 56k)
Also called dial-up
access, it is both economical and slow. Using a modem
connected to your PC,
users connect to the Internet
when the computer
dials a phone number (which is provided by your ISP)
and connects to the network.
Dial-up
is an analog
connection because data
is sent over an analog,
public telephone network.
The modem
converts received analog
data
to digital
and vise versa. Because dial-up
access uses normal telephone lines the quality of
the connection is not always good and data
rates are limited.
ISDN
Integrated Services Digital Network (ISDN)
is an international communications standard for
sending voice, video, and data
over digital
telephone lines or normal telephone wires.
B-ISDN
Broadband ISDN is similar in function to ISDN
but it transfers data
over fiber optic telephone lines, not normal
telephone wires. SONET
is the physical transport backbone
of B-ISDN.
Broadband ISDN has not been widely implemented.
DSL
DSL
is also called an always on connection because it
uses existing 2-wire copper telephone line connected
to the premise and will not tie up your phone as a dial-up
connection does. There is no need to dial-in to your
ISP
as DSL
is always on. The two main categories of DSL
for home subscribers are called ADSL
and SDSL.
ADSL
ADSL
is the most commonly deployed types of DSL
in North America. Short for Asymmetric Digital
Subscriber Line, ADSL
supports data
rates of from 1.5 to 9 Mbps
when receiving data
(known as the downstream
rate) and from 16 to 640 Kbps
when sending data
(known as the upstream
rate). ADSL
requires a special ADSL
modem.
SDSL
SDSL
is still more common in Europe. Short for
Symmetric Digital Subscriber Line, a technology
that allows more data
to be sent over existing copper telephone lines (POTS).
SDSL
supports data
rates up to 3 Mbps.
SDSL
works by sending digital
pulses in the high-frequency area of telephone
wires and can not operate simultaneously with
voice connections over the same wires. SDSL
requires a special SDSL
modem.
SDSL
is called symmetric because it supports the same data
rates for upstream
and downstream
traffic.
VDSL
Very High DSL (VDSL)
is a DSL
technology that offers fast data
rates over relatively short distances — the
shorter the distance, the faster the connection
rate.
Cable
Through the use of a cable modem
you can have a broadband
Internet
connection that is designed to operate over cable TV
lines. Cable Internet
works by using TV channel space for data
transmission, with certain channels
used for downstream
transmission, and other channels
for upstream
transmission. Because the coaxial cable used by
cable TV provides much greater bandwidth
than telephone lines, a cable modem
can be used to achieve extremely fast access.
Wireless Internet
Connections
Wireless Internet,
or wireless broadband,
is one of the newest Internet
connection types. Instead of using telephone or
cable networks
for your Internet
connection, you use radio frequency bands. Wireless Internet
provides an always-on connection which can be
accessed from anywhere — as long as you
geographically within a network
coverage area. Wireless access is still considered
to be relatively new, and it may be difficult to
find a wireless service provider in some areas. It
is typically more expensive and mainly available in
metropolitan areas.
T-1
Lines
T-1
lines are a popular leased line option for
businesses connecting to the Internet
and for ISPs
connecting to the Internet
backbone.
It is a dedicated phone connection supporting data
rates of 1.544Mbps.
A T-1
line actually consists of 24 individual channels,
each of which supports 64Kbps.
Each 64Kbps
channel
can be configured to carry voice or data
traffic. Most telephone companies allow you to buy
just one or some of these individual channels.
This is known as as fractional T-1
access.
Bonded T-1
A bonded T-1
is two or more T-1
lines that have been joined (bonded) together to
increase bandwidth.
Where a single T-1
provides approximately 1.5Mbps,
two bonded T-1s
provide 3Mbps
or 46 channels
for voice or data.
Two bonded T-1s
allow you to use the full bandwidth
of 3Mbps
where two individual T-1s
can still only use a maximum of 1.5Mbps
at one time. To be bonded the T-1
must run into the same router
at the end, meaning they must run to the same ISP.
T-3
Lines
T-3
lines are dedicated phone connections supporting data
rates of about 43 to 45 Mbps.
It too is a popular leased line option. A T-3
line actually consists of 672 individual channels,
each of which supports 64 Kbps.
T-3
lines are used mainly by ISPs
connecting to the Internet
backbone
and for the backbone
itself.
Satellite
Internet Over Satellite (IoS)
allows a user to access the Internet
via a satellite that orbits the earth. A satellite
is placed at a static point above the earth's
surface, in a fixed position. Because of the
enormous distances signals must travel from the
earth up to the satellite and back again, IoS
is slightly slower than high-speed terrestrial
connections over copper or fiber optic cables.
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