Wireless Home Networking - Index of

Chapter 3: Bluetooth and Other Wireless Networks
Using other existing wires
Besides powerlines, your home will probably
also have a number of phone lines and coaxial
(cable TV) cables running through your walls.
These wires can also potentially be used to
extend the reach of your wireless network without
installing new Ethernet cables in your home.
We say potentially because although these
wires definitely can do this job, no companies
are currently shipping products to consumers
that would let you use the wires this way.
In the past, a system called HomePNA (for
Home Phoneline Networking Alliance) was
widely available and did much the same thing
that HomePlug and other powerline networking
systems did, only leveraging the phone lines in
your walls. Since the last edition of this book,
HomePNA networking solutions have become
unavailable in the consumer marketplace.
That’s too bad, because the technology has
been greatly improved and works well. The
companies behind the technology have, however,
focused on the phone company market,
rather than the consumer home networking
market. HomePNA gear is found in many of the
TV set-top boxes provided where phone companies
offer television services — the technology
is used to carry TV programming from a
master set-top box to satellite set-top boxes
throughout the home.
A similar technology, called MoCA (Multimedia
over Coax) is used to carry TV programming and
other data over the coaxial cables used for
cable and satellite TV distribution. Again, like
the current version of HomePNA, MoCA is a
telephone (or cable) company technology — it’s
installed inside set-top boxes and not sold in the
form of consumer equipment that can be purchased
at the local Best Buy.
We think that this will change over time, and we
hope that it does because phone lines and
coaxial cables are better suited for carrying
data than are powerlines. Keep your eyes
peeled on these group’s Web sites (www.homepna.org
and www.mocalliance.org) to see when
consumer products become available.
The big news in home control, however, is the introduction of wireless networking
into the mix. Wireless home control networks are designed around
extremely low-power and low-cost chips that can (eventually) be built right
into all sorts of appliances and electrical devices in the home.
Home control networks are low-speed networks. Because home control networks
don’t need to be concerned with carrying a big fat stream of highdefinition
data or the 80 megabyte Windows update du jour, they can get
away with relatively puny data rates in the name of cost savings (it doesn’t
take a lot of bandwidth to say “dim the lights in the hall”).
In another effort to trim expenses, home control networks are short range
(the chips can be smaller and cheaper if they don’t transmit as much power
as, for example, an 802.11n chip). This may seem a bit counterintuitive —
after all, home control systems won’t work well if you can’t reach the devices
in your home that you want to control — but these networks overcome the
issue of short range by using a mesh topology. Mesh means that each radio in
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