Choosing a Broadband Connection
In the old days, life was simple. Your only real choice for accessing
the Internet was whether your dial-up connection used the U.S.
Robotics V.90. modem or the Rockwell K56Flex. Some ISPs supported
both, some didn't. Oh sure, if you were independently wealthy
you might consider ISDN or a satellite hookup where you could
pay for every minute or kilobyte of high-speed hookup, but those
weren't serious options for most of us.
Now you can get a broadband Internet connection for less than
you spend each month on your weekday morning latte, and that's
not counting the lemon Danish. But first there's a BIG DECISION
to be made. DSL or Cable? To help with that choice, here's a quick
review of the two technologies.
DSL (Digital Subscriber Line) is actually a group of technologies,
any of which can provide high-speed Internet access over a standard
telephone line, as long as you are close enough to a Central Office
where the phone company locates their switching equipment. DSL
provides a direct dedicated (not shared) connection between your
DSL modem and a DSLAM (Digital Subscriber Line Access Multiplexer)
at that central office. The most common form of DSL is ADSL, or
Asymmetric Digital Subscriber Line. It's called asymmetric because
it delivers a higher downstream transmission (from the Internet
to your computer) than it does upstream (from your computer to
the Internet).
Cable Internet access uses the very same cable that brings cable
TV into your home, by reserving some of cable bandwidth for Internet
traffic. The cable company has their own equivalent of a central
office, but the cable between it and your house is shared not
only between TV and Internet, but also between you and all of
your neighbors that subscribe to the same service. Incidentally,
cable Internet is also usually asymmetric, with more channels
given to downstream traffic than upstream. Most of the time that's
the best solution, because normally you will be downloading entire
web pages and all their graphics while uploading an occasional
keystroke.
With cable, distance is not the issue so much as whether the cable
has been routed to your street yet. Sharing though can be a big
issue, because the transmission can get slower and slower as more
people in your neighborhood try to download those web pages and
all their graphics.
Now, to decide which of these options is the best for you, here
are some things to consider:
A. Availability. You may live too far from the central office
to use DSL, or cable may not have come to your neighborhood yet.
If you only have one or the other, the choice is made for you.
Many areas have both, but generally DSL is more widely available
in business areas while cable is pretty much restricted to residential.
B. Cost. DSL packages vary widely. Find out not only the rate
but whether they charge for the modem and installation. Often
these are free but require a minimum contract period. Because
cable companies include basic TV service (whether you want it
or not), they often feel justified to charge a few dollars more
per month than comparable DSL service. Of course if you want crystal-clear
reception to 50+ channels anyway, that fact might sway your decision.
With both cable and DSL there may be options on cost, with more
expensive packages offering greater bandwidth. Which brings us
to the next consideration.
C. Speed. Your DSL and cable providers can both give you numbers
for upstream and downstream transmission rates, but take them
with a grain of salt. Those are maximum rates at best, and no
matter which connection option you choose, it is subject to the
conditions prevailing at any moment on the Internet on the other
side of the central office. Both DSL and cable use the same shared
links to the Internet, so no favoritism there. Cable though can
be further affected by the amount of local traffic. Ask around
your neighborhood to see what kind of experience to expect. Often
it's no problem at all, but here and there things can get pretty
grim, and that's something you want to know before you lay down
your money.
One last thing to consider is the reputation of the companies.
In practice DSL and cable have more similarities than differences,
and the quality of your service could very well depend more on
the service provider than on the technology you choose.
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