Wireless Home Networking - Index of

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Part III: Installing a Wireless Network
• Signal strength: Also called signal level in some systems, this is a
measure of the signal’s strength in dBm. The higher this number,
the better, and the more likely that you can get a full-speed connection
from your access point to your PC.
• Noise level: This is a measure of the interference that’s affecting
the wireless network in your home. Remember that electronics in
your home (such as cordless phones and microwaves) can put out
their own radio waves that interfere with the radio waves used by
your home network. Noise level is also measured in dBm, but in
this case, lower is better.
• Signal to Noise Ratio (SNR): This is the key determinant to the performance
of your wireless network. This ratio is a comparison of
the signal (the good radio waves) with the noise (the bad ones).
SNR is measured in dB, and a higher number is better.
Many link test programs not only provide an instantaneous snapshot of your
network performance but also give you a moving graph of your performance
over time. This snapshot can be helpful in two ways. First, if you have a
laptop PC, you can move it around the house to see how your network performance
looks. Second, it can let you watch the performance while you
turn various devices on and off. For example, if you suspect that a 2.4 GHz
cordless phone is killing your wireless LAN, turn on your link test and keep
an eye on it while you make a phone call.
When you grow more comfortable with your wireless LAN — and start using
it more and more — you can leverage these tools to tweak your network. For
example, you can have your spouse or a friend sit in the living room watching
the link test results while you move the access point to different spots in the
home office. Or you can use the link test with a laptop to find portions of
your house that have weak signals and then use these results to decide
where to install a second access point.