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- Integrated
Services Digital Network (ISDN) This is a step up from the dial-up
connection. You'll need a special ISDN dial-up line and other
hardware such as an ISDN router. The ISDN line has two channels so
the bandwidth is increased to 128K bps. (Bandwidth measures how
much information can travel over the line at one time. Higher
bandwidths transmit more information and download Web pages
faster.) You can split up the two channels, using one 64K bps
channel for the Internet and the other as a regular telephone
line. The downside of ISDN is that lines may be expensive to
install, there's usually a per-minute connection charge, and your
ISP may charge more for using 128K bps. Also, you must be located
within a certain range of your phone company's central
office.
- Digital leased
line These lines
come in bandwidths from 56K bps to T-1 (1.54M [million] bps) and
higher. A 56K digital leased line can support 20 users at once (as
opposed to one or two users on a dial-up 56K connection). These
leased lines have a fixed monthly rate and are always "on." Check
that you are guaranteed Internet access at any time of the day.
The digital leased line is usually purchased from your local
telephone company, but you must also purchase Internet service
from an ISP that corresponds to the size of the line.
- Digital Subscriber
Lines (DSL) This
connection uses regular phone lines to transmit both voice and
data. Because copper phone lines already run to your school, DSL
is a reasonably priced alternative to digital leased lines. DSL
comes in various bandwidths, from 128K bps to close to the speed
of T-1 digital leased lines. The price depends on the bandwidth,
so think about how many users will be on the Internet at once. A
1.5M bps line can support a few hundred users all using the
bandwidth at the same time. Check the features of the version of
DSL you're signing up for. Remember, you also have to purchase
Internet access that corresponds with your bandwidth. As with
ISDN, you need to ask your telephone company if they can service
your area.
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- Cable
Cable companies provide
Internet access via regular, black coaxial cable that you may
already use in your school. Speeds are about 1.5M bps, but
decrease as more users share this service at the same time. You
cannot yet be guaranteed a minimum bandwidth (and that means a
minimum transmission speed!), so ask about the minimum you should
expect.
- Satellite and
wireless Internet access These new technologies are probably
too expensive for schools.
Sources: Finding out
more information The following online resources offer
advice about choosing an Internet connection for your school:
Thoughts: Afterward, reflect on your
quest Ask yourself these questions:
 What are my school's Internet needs now and in the
future? Will we add more computers to the
network? Will we use the Internet for distance
learning and other bandwidth-intensive applications (such as
streaming video, audio, or compressed video such as Vtel)?
Before signing up for any
new Internet connection service, ask your ISP these questions: How many users do you have per modem? (should be 10 or
less to avoid busy signals for the dial-up accounts) What is the connect and set-up charge for the line? What is the wait time to have the connection installed?
Do you notify users via e-mail of planned
"downtime?" Will you credit our account for
"downtime" of your line? Do you
provide 24/7 phone support (24 hours a day, seven days a week)?
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