Wireless Home Networking - Index of

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Part I: Wireless Networking Fundamentals
You may run into gear using one of two older standards. For the most part,
manufacturers aren’t making gear using these systems anymore (at least not
for the home — some industrial and commercial network gear still on the
market use these systems), but you will still hear about these systems as you
explore wireless networking:
� 802.11a: Wireless networks that use the Institute for Electrical and
Electronics Engineers (IEEE) 802.11a standard use the 5 GHz radio
frequency band. Equipment of this type is among the fastest wireless
networking equipment widely available to consumers.
� 802.11b: Wireless home networks that use the 802.11b standard use the
2.4 GHz radio band. This standard is the most popular in terms of number
of installed networks and number of users.
Following are the two major wireless systems that have pretty much replaced
802.11b and 802.11a:
� 802.11g: The current member of the 802.11 wireless family to hit the
mainstream, 802.11g has rapidly taken over the market. In many ways,
802.11g offers the best of both worlds — backward compatibility with
the older 802.11b networks discussed in the next section (they too operate
over the 2.4 GHz radio frequency band) and the speed of the older
802.11a networks also discussed in that section. And the cost of 802.11g
has dropped so precipitously that it’s now less expensive than the older
and slower 802.11b. (You can buy an 802.11g network adapter for less
than $20 and a home router for less than $50.) For these reasons,
802.11g has become the de facto solution that most users now buy.
� 802.11n (draft standard): 802.11g is still the default, but it is rapidly
being replaced by a newer and faster system called 802.11n. 802.11n
(like 802.11g before it) is backward compatible, which means that older
802.11b and 802.11g systems can work just fine on an 802.11n network.
802.11n systems can also support the 5 GHz frequencies (though not all
do; more on this in Chapter 3), and may therefore be backward compatible
with 802.11a as well. A lot of new technology in 802.11n extends the
range of the network and increases the speed as well — 802.11n can be
as much as five times faster than 802.11g or 802.11a networks.
You’ll note the words draft standard in the preceding description of 802.11n.
The group that ratifies the technical specifications of wireless networks (the
IEEE, discussed in Chapter 3) has not completely finished agreeing on the
802.11n system standard. What they have in place (and what manufacturers
are building their systems around) is a draft of the final standard that’s about
99 percent of the way there (the final isn’t expected to be ratified until 2009).
Normally we would recommend that people wait for a final standard to be in
place, but 802.11n is so far along (and working so well) that we don’t hesitate
to recommend it for folks who could use the extra range or speed.