What Is DSL Internet Connection?
Unless you live or work in a remote or
very rural area, you probably have the option of giving up (if you haven't already) that slow
dial-up modem and investing in a broadband Internet
connection. If high-speed Internet services are
available, your choice is between DSL (Digital Subscriber Line) or
cable modem services. Both DSL and cable modems are common home networking
broadband connection technologies but which option is better?
DSL uses a sophisticated modulation scheme to pack data onto
copper wires. DSL is sometimes referred to as a last-mile technology
because it is used only for connections from a telephone switching
station to a home or office, not used between switching stations. DSL is also
called an always on connectionm 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 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
rate) and from 16 to 640 Kbps when sending data (known as the
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.
Two other types of DSL
technologies are High-data-rate DSL (HDSL) and Very high DSL (VDSL).
VDSL offers fast data rates over relatively short distances - the
shorter the distance, the faster the connection rate. Collectively, all types of DSL are referred
to as xDSL.
Key Terms To
Understanding cable modem
A modem designed to operate over cable TV lines.
A type of data transmission in which a single medium (wire) can
carry several channels at once.
Refers collectively to all types of digital subscriber lines, the
two main categories being ADSL and SDSL.
Short for Internet Service Provider, a company that provides access
to the Internet.
More Cable Vs. DSL
A computer network that spans a relatively small area.
A modem is a device or program that enables a computer to transmit
data over, for example, telephone or cable lines.
A system designed to prevent unauthorized access to or from a
What Is a Cable Internet Connect?
Through the use of a
cable modem you can have a
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
to the Web. This, combined with the fact that millions of homes
are already wired for cable TV, has made cable Internet service something cable TV companies
have really jumped onboard with.
Cable vs. DSL: The Speeds
The topic of "which is better and faster" has been a highly debated
topic, and still there doesn't appear to be a clear winner.
DSL offers users a choice of speeds ranging
from 144 Kbps to 1.5Mbps. Cable modem download speeds are typically up to 2
times faster than 1.5Mbps DSL, but the reason there is no clear speed winner
is because cable technology is based on shared bandwidth, with many factors
influencing a users download speed. With shared bandwidth the speed
fluctuates depending on the number of subscribers on the network. With DSL,
the connection is yours and not shared, and you tend to have a more constant
speed. This is one reason why cable Internet providers don't often publish
speed information. In more rural areas with fewer subscribers, you're bound
to have faster download speeds than a subscriber in a metropolitan center.
Because cable modem speeds fluctuate, it is difficult to gauge an exact
download speed. On the upload stream, however, cable and DSL are closely
matched for speed. Both DSL and cable Internet speeds are largely dependant
on the service provider and either the distance away from the switching
station you are or how many subscribers are in your immediate area.
Cable vs. DSL: Home Networking & Security
Both DSL and Cable Internet can easily be shared with computers on your home
LAN through software (Microsoft
Internet Connection Sharing for example) or
by using a connection sharing device, such as a
software. Using a SOHO router
is most-often the recommended option as this will also provide you with a much needed
firewall protection for your LAN as well. It is important to
check with your service provider, however, as sharing your broadband connect
may violate your Terms of Service agreement. In many areas, service providers
will allow you to connect additional computers to your broadband Internet
service for a nominal fee. Because Cable is shared connection, you are
actually on a
with all subscribers in your areas. This would really create security
issues only if no security measures are in place, but cable service providers
generally provide cable modems with security features in the hardware.
Overall the security of these broadband connections are closely matched,
with DSL boasting a bit better security and it is always advisable to
consider purchasing additional hardware or software to protect your system,
as your service provider may only provide the basics with the installation &
set-up of your account.
Cable vs. DSL: The Price
The price consumers will pay for DSL or cable Internet services is not
standard. It depends on how much competition there is for broadband
services, and the area you live in. For example, in some areas it's only been
in the past few years that cable Internet has been available. Until
then, DSL costs were quite high, but as cable Internet became available the
price of DSL went down. With either option you generally will pay a one-time
set-up fee. For cable you could expect this fee to be anywhere from $50 to
$100, while the cost for DSL installation is a bit more and could run up to
$150 for set-up. Once the installation is completed, you will usually pay
for your Internet subscription on a monthly basis. Cable, again, is usually
a bit cheaper with monthly fees averaging $40 to $50. You can expect to pay
about $5 to $10 more a month for DSL service.
If you live in an area where both cable and
DSL is offered then you may find yourself being able to nab a better deal on
your broadband service. Your local DSL or cable carrier may offer
introductory offers such as free installation or offer the Internet service
free for a couple months. In addition, you can also check and see if the
service provider offer discounts on service bundles. For example, many cable
companies offer discounts for "surf and watch" which gives you a price
discount if you subscribe to both cable TV and cable Internet from the same
provider (also many cable operators now offer VoIP capabilities as part of the mix). If you choose DSL you may qualify for a "surf and talk" bundle
plan. If you're not already a broadband subscriber you can save money by
checking with local service providers and signing up for your broadband
account when you can catch a good deal.
Did You Know...
In "perfect" conditions, cable download speeds are up to 2 times
faster than 1.5Mbps DSL speeds, Which is roughly 50 times faster
than 28.8K Modem.
Vangie 'Aurora' Beal
Last updated: June 03, 2005
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information for setting up Internet sharing found anywhere!