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setup software. (Cat 5e cable is a standard Ethernet cable or patch cord
with what look like oversized phone jacks on each end. You can pick one
up at any computer store or RadioShack.)
If you™re not, you need to connect a Cat 5e cable between the AP and one
of the router™s Ethernet ports and then connect another cable from
another one of the router™s Ethernet ports to the computer on which
you are running the setup software.
4. Complete the installation of the setup software and when prompted,
enter the information that you collected in Step 1 (so have that infor-
mation handy).
5. Record the following access point parameters.
The following list covers AP parameters that you will most often
encounter and need to configure, but it is not comprehensive. (Read
more about them in the following section, “Configuring AP parameters.”)
You will need this information if you plan to follow the steps on modify-
ing AP configuration, which we cover in the later section, “Changing the
AP Configuration.” (What did you expect that section to be called?)
Other settings that you probably don™t need to change include the trans-
mission rate (which normally adjusts automatically to give the best
throughput), RTS/CTS protocol settings, the beacon interval, and the
fragmentation threshold.
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Chapter 6: Installing Wireless Access Points in Windows

• Service set identifier (SSID)
• Channel
• WEP keys
• Password
• MAC address
• Dynamic or static wide area network (WAN) IP address
• Local IP address
• Subnet mask
• PPPoE (Point-to-Point Protocol over Ethernet)




Figure 6-2:
It™s time to
connect the
AP or
Internet
gateway.



6. Complete the installation software and you™re finished.
After you complete the AP setup process, you should now have a work-
ing access point ready to communicate with another wireless device.



Configuring AP parameters
Here™s a little more meat on each of the access point parameters that you
captured in Step 5 of the preceding section.

Service set identifier (SSID): The SSID (sometimes called the network
name, network ID, or service area) can be any alphanumeric string,
including upper- and lowercase letters, up to 30 characters in length.
The AP manufacturer might set a default SSID at the factory, but you
112 Part III: Installing a Wireless Network

should change this setting. Assigning a unique SSID doesn™t really add
much security; nonetheless, establishing an identifier that is different
than the factory-supplied SSID makes it a little more difficult for intrud-
ers to access your wireless network. And if you have a nearby neighbor
with a wireless AP of the same type, you won™t get the two networks con-
fused. When you configure wireless stations, you need to use the same
SSID/network name that is assigned to the AP.
Channel: This is the radio channel over which the AP will communicate.
If you plan to use more than one AP in your home, you should assign a
different channel (over which the AP will communicate) for each AP to
avoid signal interference. If your network uses the IEEE 802.11b or IEEE
802.11g protocols, 11 channels, which are set at 5 MHz intervals, are
available in the United States. However, because the radio signals used
by the IEEE 802.11b standard spread across a 22 MHz-wide spectrum,
you can only use up to three channels (typically 1, 6, and 11) in a given
wireless network.
If you™re setting up an 802.11a AP, you have 11 channels from which to
choose. But because these channels are 20 MHz wide and do not over-
lap, you really have 11 channels with which to work, compared with only
3 with IEEE 802.11b or 802.11g. If you operate only one AP, all that really
matters is that all wireless devices on your network must be set to the
same channel. If you operate several APs, give them as much frequency
separation as possible to reduce the likelihood of mutual interference.
Table 6-1 contains the channel frequencies for the different wireless
standards.


Table 6-1 Channel Frequencies for Wireless Standards
2.4 GHz (802.11b/g) 5 GHz (802.11a)
Channel 1“2.412 GHz Channel 36“5.180 GHz
Channel 2“2.417 GHz Channel 40“5.200 GHz
Channel 3“2.422 GHz Channel 44“5.220 GHz
Channel 4“2.427 GHz Channel 48“5.240 GHz
Channel 5“2.432 GHz Channel 52“5.260 GHz
Channel 6“2.437 GHz Channel 56“5.280 GHz
Channel 7“2.422 GHz Channel 60“5.300 GHz
Channel 8“2.447 GHz Channel 64“5.320 GHz
Channel 9“2.452 GHz
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Chapter 6: Installing Wireless Access Points in Windows


2.4 GHz (802.11b/g) 5 GHz (802.11a)
Channel 10“2.457 GHz
Channel 11“2.462 GHz
Channel 12“2.467 GHz
Channel 13“2.472 GHz
Channel 14“2.477 GHz (Japan only)
Notes
802.11b/g:
Channel 3 is default FCC, ETSI, Japan.
Channel 12 is for ETSI countries only.
For France, Channels 10“13 are applicable only.
802.11a:
These channels are valid only in US/Canada and Japan at this time.
Source: ORiNOCO



Some access points, such as some from ORiNOCO, offer an automatic
channel selection feature, which is cool. For instance, the ORiNOCO
AP-2000 Access Point selects its own frequency channel, based on inter-
ference situation, bandwidth usage, and adjacent channel use, using its
Auto Channel Select feature. This is beneficial when first deploying
your AP-2000 or adding an AP-2000 unit in an existing environment. For
instance, for the 5 GHz radio card (used for 802.11a), the default channel
is 52 (5.260 GHz). When a second AP-2000 unit is turned on in the vicin-
ity of the currently active AP-2000 device, the Auto Channel Select fea-
ture changes the frequency channel of the second unit so there is no
interference between the units. Multiple AP-2000 units can be turned on
simultaneously to establish proper channel selection. That™s pretty nice;
you might wonder why it™s necessary to pay more for more business-
class access points ” this is a good reason.
When you have multiple access points and set your 802.11a, b, or g
access points all to the same channel, sometimes roaming won™t work
when users move about the house, and the transmission of a single
access point blocks all others that are within range. As a result, perfor-
mance degrades significantly. (You notice this when your throughput, or
speed of file/data transfers, decreases noticeably.) Use different, widely
separated channels for b and g; you only have to use different channels
for a because they are non-overlapping.
WEP keys: You should always use Wired Equivalent Privacy (WEP)
encryption. Only a determined hacker with the proper equipment and
software will be able to crack the key. (By the time that you™re reading
this, newer encryption protocols such as Wi-Fi Protected Access [WPA]
might have been implemented that are nearly impossible to break.) If you
don™t use WEP or some other form of security, any nosy neighbor with a
laptop, wireless PC card, and range-extender antenna might be able to see
114 Part III: Installing a Wireless Network

and access your wireless home network. Whenever you use encryption,
all wireless stations in your house attached to the wireless home network
must use the same key. Sometimes the AP manufacturer will assign a
default WEP key. Always assign a new key to avoid a security breach.
Read Chapter 10 for great background info on WEP and WPA.
Password: Configuration software might require that you enter a pass-
word to make changes to the AP setup. The manufacturer might provide
a default password (see the user documentation). Use the default pass-
word when you first open the configuration pages, and then immediately
change the password to avoid a security breach. (Note: This is not the
same as the WEP key, which is also called a password by some user inter-
faces [UIs].)
MAC address: The Media Access Control (MAC) address is the physical
address of the radio in the AP. You should find this number printed on a
label attached to the device. You might need to know this value for trou-
bleshooting, so write it down. The AP™s Ethernet (RJ-45) connection to
the wired network also has a MAC address that is different than the MAC
address of the AP™s radio.
Dynamic or static wide area network (WAN) IP address: If your net-
work is connected to the Internet, it must have an IP address assigned
by your ISP. Most often, your ISP will dynamically assign this address.
Your router or Internet gateway should be configured to accept an IP
address dynamically assigned by a DHCP server. It is possible, but
unlikely, that your ISP will require a set (static) IP address.
Local IP address: In addition to a physical address (the MAC address),
the AP will also have its own network (IP) address. You need to know
this IP address to access the configuration pages using a Web browser.
Refer to the product documentation to determine this IP address. In
most cases, the IP address will be 192.168.xxx.xxx where xxx is between
1 and 254. It™s also possible an AP could choose a default IP that™s in use
by your cable/DSL router (or a computer that got its IP from the
cable/DSL router™s DHCP server). Either way, if an IP conflict arises, you
might have to keep the AP and cable/DSL routers on separate networks
while configuring the AP.
Subnet mask: In most cases, this value will be set at the factory to 255.
255.255.0. If you™re using an IP addressing scheme of the type described in
the preceding paragraph, 255.255.255.0 is the correct number to use. This
number, together with the IP address, establishes the subnet on which
this AP will reside. Network devices with addresses on the same subnet
can communicate directly without the aid of a router. You really don™t
need to understand how the numbering scheme works except to know
that the AP and all the wireless devices that will access your wireless net-
work must have the same subnet mask.
PPPoE: Most DSL ISPs use of Point-to-Point Protocol over Ethernet
(PPPoE). The values that you need to record are the user name
(or user ID) and password.
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Chapter 6: Installing Wireless Access Points in Windows


Changing the AP Configuration
Each brand of AP has its own configuration software that you can use to
modify the AP™s settings. Some products provide several methods of configu-
ration. The most common types of configuration tools for home/small office
APs are

Software-based: Some APs come with access point setup software that
you run on a workstation to set up the AP over a wireless connection, a
USB cable, or an Ethernet cable.
Web-based: Many of the newer lines of APs intended for home and small
office use have a series of HyperText Markup Language (HTML; Web)
forms stored in firmware. You can access these forms by using a Web
browser over a wireless connection or over a network cable in order to
configure each AP.

To access your AP™s management pages with a Web browser, you need to know
the local IP address for the AP. If you didn™t make note of the IP address when
you initially set up the AP, refer to the AP™s user guide to find this address. It
will be a number similar to 192.168.2.1. If you™re using an Internet gateway, you
can also run winipcfg (on Windows 9x/Me machines) or ipconfig (Windows
NT, 2000, XP), as we describe in Chapter 7. The Internet gateway™s IP address is
the same as the default gateway.

When you know the AP™s IP address, run your Web browser software, type
the IP address in the Address line, and then press Enter or click the Go
button. You™ll probably see a screen that requests a password. This is the
password that you established during initial setup for the purpose of prevent-
ing unauthorized individuals from making changes to your wireless AP™s con-
figuration. After you enter this password, the AP utility will display an AP
management screen. If you™re not using a Web-based tool, you need to open
up the application that you initially installed to make any changes.

Within the AP™s management utility, you can modify all the AP™s settings such
as the SSID, the channel, and WEP encryption key. The details of how to make
these changes vary from manufacturer to manufacturer. Typically, the AP
management utility also enables you to perform other AP management opera-
tions, such as resetting the AP, upgrading its firmware, and configuring any
built-in firewall settings.

AP manufacturers periodically post software on their Web site that you
can use to update the AP™s firmware that™s stored in the circuitry inside
the device. If you decide to install a firmware upgrade, follow the provided
instructions very carefully. Note: Do not turn off the AP or your computer
while the update is taking place.
116 Part III: Installing a Wireless Network

The best practice is to modify AP settings only from a computer that™s directly
connected to the network or the AP by a network cable. If you must make
changes over a wireless connection, think through the order that you will
make changes, or you could orphan the client computer. For example, if you
want to change the wireless network™s WEP key, change the key on the AP first
and make sure that you write it down. As soon as you save the change to the
AP, the wireless connection will effectively be lost. No data will pass between
the client and the AP, so you will no longer be able to access the AP over the
wireless connection. To re-establish a useful connection, you must change the
key on the client computer to the same key that you entered on the AP.
Chapter 7
Setting Up Your Windows PCs for
Wireless Networking
In This Chapter
Installing wireless network interface adapters
Windows XP™s Wireless Zero Configuration
Going wireless with Pocket PC 2002




I n this chapter, we describe the installation and configuration of wireless

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