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Networking: A Beginner's Guide
As a rule of thumb, you can estimate that the demands placed on a desktop
computer will double every 24 months or so, taking into account your planned
useful life. Set your performance levels to meet that need. (People used to assume
performance requirements doubled every 18 months, but this seems to be slowing
a bit in recent years.)
For example, suppose that you've determined that today's user requires 40GB of
disk space, 2GB of RAM, and a Pentium 2.8 GHz processor. In 24 months, your users are
likely to be clamoring for 80GB of disk space, 4GB of RAM, and a Pentium quad-core
3 GHz processor. In another 24 months (about four years from purchase), these demands
will double again, to 160GB of disk space, 8GB of RAM, and the equivalent of a Pentium
8-core processor. These projected demands might seem unlikely today, but when you
look back at the needs of four years ago, such projections seem reasonable.
Using this way of estimating performance needs, you should be able to find a
"sweet spot" between price, performance, and useful life that minimizes your costs and
maximizes the benefits that your users will receive.
Understanding Network Workstation Requirements
Computers connected to a local area network (LAN) differ slightly from computers that
stand alone. They have additional hardware installed in them, and they run additional
network software. This section explores these differences.
Network Workstation Hardware
All network computers need an installed network interface to connect to the network.
Generally, most desktop computers these days have an intergrated Ethernet network
interface built-into them. And if a computer does not, then it can be added as a network
interface card.
NICs are also usually specific to the cable media you have installed. For example,
Ethernet NICs are available for 10Base-2, 10Base-T, 100Base-T, and 1000Base-T media.
DEFINE-IT! Useful Life
The term useful life refers to the length of time a particular asset, such as a computer,
will be able to perform useful work. The useful life of a computer will change
depending on the computer, the software it needs to run, the user who uses it, and
the budget available to upgrade or replace it. A programmer who needs the latest
and greatest hardware and software all the time will get a relatively short useful life
out of a computer, while a person who uses a computer only for word processing
or e-mail and doesn't care about running the latest software will get a much longer
useful life out of a computer. For most desktop computers, the useful life is around
three to four years, although exceptions to this rule of thumb are easy to find.