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integral router/DSL/cable modem ” so that you can add more ports to
your network while it grows. (And it will grow.)




Security
Unless you work for the government or handle sensitive data on your com-
puter, you probably aren™t overly concerned about the privacy of the informa-
tion stored on your home network. Usually it™s not an issue, anyway, because
someone would have to break into your house to access your network. But if
you have a wireless network, the radio signals transmitted by your wireless
network don™t automatically stop at the outside walls of your house. In fact, a
neighbor or even someone driving by on the street in front of your house can
use a computer and a wireless networking adapter to grab information right
off your computer, including deleting your files, inserting viruses, using your
computer to send spam, and so on ” unless you take steps to protect your
network.

The security technology that comes standard with all Wi-Fi equipment is
Wired Equivalent Privacy (WEP). Perhaps the most well-publicized aspect
of Wi-Fi wireless networking is the fact that the WEP security feature of Wi-Fi
networks can be hacked (broken into electronically). Hackers have success-
fully retrieved secret WEP keys used to encrypt data on Wi-Fi networks. With
these keys, the hacker can decrypt the packets of data transmitted over a
wireless network. The significance of this problem might have been overblown
96 Part II: Making Plans

in the media because changing keys regularly greatly reduces the risk of a
successful WEP attack. Nonetheless, many business and government agen-
cies have prohibited implementation of wireless networks that rely only on
WEP to protect the privacy of data.

In October 2002, the Wi-Fi Alliance announced a new, replacement security
technology for WEP: Wi-Fi Protected Access (WPA). WPA is based on an IEEE
standards effort that™s not yet fully adopted. This technology, which makes
cracking a network™s encryption key much more difficult, is designed to work
in the products on the market today and is expected to first appear in Wi-Fi
certified products during the first quarter of 2003. Most vendors are expected
to offer free firmware and software updates for Wi-Fi certified products cur-
rently in use.

Although WEP isn™t as secure as WPA, you take a much greater security risk if
you don™t use WEP at all. See Chapter 10 for a full discussion of how to set up
basic security for your wireless home network.

In addition to encryption features such as WEP (or WPA), many AP manufac-
turers have added a variety of security features often described loosely as
firewall protection. One of the most common security features is typically
described as a MAC filter because it enables you to set up a list of Media
Access Control (MAC) addresses that are permitted to access the network.
(The manufacturer of each networking device assigns a unique MAC address
to the device at the factory.) A MAC filter can prevent network access by
devices not on a predetermined list of MAC addresses.

Don™t depend on the MAC filter feature as the sole form of security for your
wireless home network. A determined hacker can discover the MAC address
of one of your computers and then use software to masquerade as that MAC
address. The AP would permit the hacker to join the network. This is a spoof
attack.

Other useful firewall features to look for when buying an AP include

Network Address Translation (NAT), which we discuss earlier in this
chapter
Virtual Private Network (VPN) pass-through that allows wireless net-
work users secure access to corporate networks
Monitoring software that logs and alerts you to computers from the
Internet attempting to access your network
Utilities that enable you to log content that™s transmitted over the net-
work as well as to block access to given Web sites

We talk a lot more about security in Chapter 10. We encourage you to read
Chapter 10 so that you™ll be well prepared for the process when you™re ready
to install your equipment.
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Chapter 5: Choosing Wireless Home Networking Equipment


Range and Coverage Issues
An AP™s functional range (the maximum distance from the access point at
which a device on the wireless network can receive a useable signal) and
coverage (the breadth of areas in your home where you have an adequate
radio signal) are important criteria when selecting an AP. Wi-Fi equipment is
designed to have a range of up to 100 meters when used outdoors without any
obstructions between the two radios. Coverage depends on the type of
antenna used.

Just like it™s hard to know how good a book is until you read it, it™s hard to
know how good an AP is until you install it. Buying an AP is definitely the
type of thing for which you do your research ahead of time and hope that you
make the right choice. Buying ten APs and returning the nine that you don™t
want is simply impractical. (Well, maybe not impractical, but rather rude.)
The key range and coverage issues, such as power output, antenna gain, or
receive sensitivity (which we cover in Chapter 2) aren™t well labeled on retail
boxes. Nor are these issues truly comparable among devices, either, because
of the same lack of consistent information. Because many of these devices
are manufactured by using the same chipsets, performance usually doesn™t
vary extensively from one AP to another. However, that is a broad generaliza-
tion, and some APs do perform badly. Our advice: Read the reviews and be
forewarned!

In Chapter 2, we tell you about the differences in range between 802.11b/g
systems and 802.11a systems, with the latter having slightly less range, all
other things being equal. Of the many good reasons to go for 802.11a sys-
tems, a big one is the lack of interference in the 5 GHz frequency range. And if
you have range issues, we help you figure out how to boost that range (and
your throughput) in Chapter 18.




Manageability
When it comes to installing, setting up, and maintaining your wireless net-
work, you™ll rely a lot on your device™s user interface, so check reviews for
this aspect of the product. In the next sections, we discuss the many different
ways to control and manage your devices.



Web-based configuration
APs, wireless clients, and other wireless devices from all vendors ship with
several utility software programs that help you set up and configure the device.
An important selling feature of any wireless device is its setup process. The
98 Part II: Making Plans

ideal setup procedure can be accomplished quickly and efficiently. Most
available APs and devices can be configured either through the wired
Ethernet port or through a USB port.

The best setup program varieties enable you to configure the device by con-
necting through the Ethernet port and accessing an embedded set of Web
(HyperText Markup Language; HTML) pages. Look for an AP with one of
these. This type of setup program ” often described as Web-based ” can be
run from any computer that™s connected to the device™s Ethernet port and
that has a Web browser. Whether you™re using Windows, the Mac OS, or
Linux, you™ll be able to access any device that uses a Web-based configura-
tion program.



Software programming
When shopping for an AP, look for one with an automated setup process.
Several AP manufacturers provide setup software that walks you step by step
through the entire process of setting up the AP and connecting to your net-
work. The Windows variety of automated setup programs are typically called
wizards. If you™re new to wireless technology, a setup wizard or other variety
of automated setup program will help you get up and running with minimum
effort.

Versions of Windows starting with Windows XP and versions of the Mac OS
starting with Mac OS 9 are more wireless aware than earlier versions of these
operating systems. Automated setup programs are typically quick and easy
to use when written to run on either Windows XP or Mac OS 9 or later.




Performing firmware updates
Most firmware updates come in the form of a Never turn off the computer or the AP while
downloadable program that you run on a com- the firmware update is in progress.
puter connected to the AP (or other device) by
If something does go wrong, look through
a cable (usually Ethernet but sometimes USB).
the AP documentation for instructions on
Make sure that you carefully read and follow
how to reset the modem back to its factory
the instructions that accompany the download-
settings.
able file. Updating the firmware incorrectly can
lead to real headaches. Here are a few tips:
Make sure that you make a backup of your
current firmware before performing the
update.
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Chapter 5: Choosing Wireless Home Networking Equipment

Even if an AP comes with a setup wizard, it will also ship with configuration
software that permits you to manually configure all the available AP settings.
For maximum flexibility, this configuration software should be Web based
(see the preceding section).



Telnetting to your device
When all else fails, you can rely on some good old, stand-by backdoors in
computing. With your computer, it™s the command prompt interface. With
your wireless device, it™s telnetting, which sounds very Scandinavian but isn™t
even close. Telnet is a terminal emulation program for TCP/IP networks such
as the Internet; a terminal emulation program emulates what you would see if
you were sitting at a terminal attached to the device that you want to
manage. The Telnet program runs on your computer and links your PC to a
device on the network: in this case, your AP. You can then enter commands
through the Telnet program, and they will be executed as if you were entering
them directly into the AP or through the manufacturer™s Web-based program.

To start a Telnet session, you enter the IP address of the device and log in by
entering a valid username and password. You will then be presented with a
screen that is decidedly old-fashioned, but you can get the job done here. In
order to telnet to a device, you might have to connect with it via a serial inter-
face cable or a null modem cable like a cross-over Ethernet cable (an Ethernet
cable with certain wires reversed). Danny recently had to use Telnet to manage
a dialup router that he had just purchased on eBay because the software pro-
vided with the router wouldn™t support XP . . . but he could get in via telnetting.

Windows ships with a free Telnet program: HyperTerminal. If you find that
your software won™t work and you need to get to the device, ask Technical
Support whether you can telnet to the device (and leave the skis at home).



Upgradeable firmware
Wireless networking technology is still evolving. As a result, many features of
Wi-Fi access points are implemented in updateable chips known as firmware.
Before you decide which AP to buy, determine whether you™ll be able to get
feature updates and fixes from the vendor and whether you can perform the
updates by upgrading the firmware (see the nearby sidebar “Performing
firmware updates” for some pointers). Check also for updated management
software to match up with the new or improved features included in the
updated firmware.
100 Part II: Making Plans

You might feel that frequent firmware updates are evidence of faulty product
design. Acknowledging that wireless technology will continue to be improved,
buying a product that can be upgraded to keep pace with these changes with-
out the need to purchase new equipment can save you money in the long run.




Price
Although we can™t say much directly about price (except that the least expen-
sive item is rarely the one that you want), we should mention other things
that can add to the price of an item. Check out which cables are provided
(yes, wireless devices need cables, too!). In an effort to trim costs, some (not
many) companies don™t provide an Ethernet cable for your AP (which you
need for initial setup).

Also, before you buy, check out some of the online price comparison sites,
like CNET (shopper.cnet.com) or Yahoo! Shopping (shopping.yahoo.com).
Internet specials pop up all the time.




Warranties
There™s nothing worse than a device that dies one day after the warranty
expires. The good news is that because most of these devices are solid state,
they work for a long time unless you abuse them by dropping them on the
floor or something drastic. In our experience, if your device is going to fail for
build reasons, it will do so within the first 30 days or so.

You™ll encounter a rather large variance among vendors of warranty sched-
ules. Some are only one-year long, but some are lifetime in length. Most are
limited in some fashion, like covering parts and labor but not shipping.

When purchasing from a store, be sure to ask about its return policy for the
first month or so. A lot of stores give you 14 days to return items, and after
that, purchases have to be returned to the manufacturer directly, which is a
huge pain in the rumpus, as Pat would say. If you only have 14 days, get the
device installed quickly so that you can find any problems right away.

Extended service warranties are also often available through computer retail-
ers. (We never buy these because by the time that the period of the extended
warranty expires, they™re simply not worth their price given the plummeting
cost of the items.) If you purchase one of these warranties, however, make
sure that you have a clear understanding of the types of problems covered as
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Chapter 5: Choosing Wireless Home Networking Equipment

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