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Networking: A Beginner's Guide
Whether you choose remote node or remote control, you then must determine
how the users will connect to the LAN. A variety of different ways exist to make this
connection, as discussed in the following sections.
To Modem or Not To Modem, That Is the Question ...
Remote users can connect to your network in two ways: through devices connected to
the network in some fashion, or by connecting to an ISP and then accessing the network
over the LAN's Internet connection. For example, users can use a modem to dial in to a
modem connected to the LAN that you maintain. Alternatively, users can use a modem
to connect to a modem managed by an ISP and then make use of the LAN's connection
to the Internet to get into the LAN.
For small networks, it can often be easiest to simply add a modem or two to a
computer set up to accept remote connections, and then let the users use those modems
to connect. You can set up the modems on individual PCs that run remote control
software, on PCs that run remote node software (such as Windows Routing and
Remote Access Service), or on special LAN-connected interfaces built for the purpose
of providing remote node connections.
You can also build your own "modem farms" with tens or hundreds of modems,
using special hardware that supports such uses. However, it can be a real hassle to
manage your own modems--not only do you need to manage the modems themselves,
but also the remote node software and hardware, the telephone lines used, and all the
problems that can occur at any time.
If a LAN already has a high-speed link to the Internet, such as through a fractional
or full T-1, it can be easier to let the remote users dial in to a local ISP and then connect
to the LAN through the Internet. Such a setup has many advantages:
No need to support modems directly
You don't need to worry about
managing the modems. If users can't connect, they can call the ISP for
connection help. Larger ISPs have round-the-clock support staff in place to
provide such help, which beats getting woken up at 2:00
A
.
M
. because a user in
Europe can't connect.
No long-distance tolls
The ISP connection is usually a local call, saving
money on long-distance charges that may be incurred when dialing the LAN
directly.
Minimal impact on LAN performance
Using the LAN's Internet connection
usually doesn't affect the LAN users who also use that connection, for two
reasons. First, many remote users connect to the LAN outside normal working
hours when the Internet connection probably isn't being used much. Second,
because the remote user is often connected to the ISP through a slower
connection, the total impact to your high-speed Internet link is minimal, even
during working hours.