Wireless Home Networking - Index of

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Part V: The Part of Tens
deck of cards) for communities. While you can buy a couple for yourself, they
want to sell these to whole neighborhoods so you and your friends can build
your own wireless mesh network. At its most basic level, a repeater simply
regenerates a wireless network signal to extend the range of the existing wireless
LAN. You set the two devices to the same channel with the same service
set identifier (SSID), thus effectively broadening the collective footprint of
the signal.
If you have throughput performance issues because of interference or reach,
putting an AP into repeating mode may help extend the reach of your network.
However, it’s not clear that adding a repeater helps actual throughput in all
situations, unfortunately. Some testing labs have cited issues with throughput
at the main AP because of interference from the new repeating AP (which
is broadcasting on the same channel). Others note that the repeater must
receive and retransmit each frame (or burst of data) on the same RF channel,
which effectively doubles the number of frames that are sent. This effectively
cuts throughput in half. Some vendors have dealt with this through software
and claim that it’s not an issue.
It’s hard at this juncture to make a blanket statement about the basic effectiveness
of installing an AP in repeater mode, particularly versus the option
of running a high-quality Ethernet cable to a second AP set on a different
channel. If you can do the latter, that’s preferable.
When you’re using the bridging and repeating functions of APs and bridges,
we recommend that you use products from the same manufacturer at both
ends of the bridge, to minimize any issues between vendors. Most companies
support this functionality only between their own products and not across
multiple vendors’ products.
Check Your Cordless Phone Frequencies
The wireless frequencies at 2.4 GHz and 5.2 GHz are unlicensed (as we define
in Part I of this book), which means that you, as the buyer of an AP and
operator of a wireless broadcasting capability, don’t need to get permission
from the FCC to use these frequencies as long as you stay within certain
power and usage limitations as set by federal guidelines. It also means that
you don’t have to pay any money to use the airwaves — because no license
is required, it doesn’t cost anything.
Many consumer manufacturers have taken advantage of free radio spectrums
and created various products for these unlicensed frequencies, such as
cordless phones, wireless A/V connection systems, RF remote controls, and
wireless cameras.