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?
What Is DSL Internet Connection? 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 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.
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
cable modem A modem designed to operate over cable TV lines.
broadband A type of data transmission in which a single medium (wire) can carry several channels at once.
xDSL Refers collectively to all types of digital subscriber lines, the two main categories being ADSL and SDSL.
ISP Short for Internet Service Provider, a company that provides access to the Internet.
More Cable Vs. DSL Terms
local-area network A computer network that spans a relatively
small area.
modem A modem is a device or program that enables
a computer to transmit data over, for example, telephone or cable lines.
firewall A system designed to prevent unauthorized access
to or from a private network. |
What Is a Cable Internet Connect? 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 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 router and firewall
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 LAN 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. |
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