|Key to Instructions
To help readers follow the
instructions in this article, we used two
is used to identify the names of
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and instructions users should type into
ould you like to access the
Internet, your printer and your other computers,
including laptops, without stringing wires
throughout your office or home? The solution is a
wireless local area network (WLAN) and we’ll tell
you how easy it is to install one yourself at a
WLANs replace conventional
wires with devices called wireless access points
that plug into any electrical wall socket. WLAN
hardware contains miniature transmitters and
antennae that send and receive radio signals to
and from your computers and other peripherals.
In order to determine how many access points
you will need and where they should be placed,
sketch the layout of your home or office.
Consumer-grade access points have an average
effective indoor range of up to 150 feet, though
thick concrete walls, metal wall studs and
appliances can reduce that range. A small office
may need just one access point, which can cost as
little as $70. Powerful commercial devices, which
provide coverage of extended areas, either indoor
or outdoor, cost as much as several thousand
You also will need to install in
each computer, printer and peripheral a wireless
network interface card (NIC), which contains a
transmitter and antenna to send and receive
signals from an access point. Wireless NICs cost
from $40 to several hundred dollars. A $40 model
is adequate for a home or small office WLAN.
SELECT THE STANDARD
When you shop for
wireless equipment, you will be asked which of
three industry WLAN industry standards you plan to
employ—802.11b, 802.11a or 802.11g. All wireless
equipment uses one or more of these standard
specifications. The 802.11b designation was the
first to be deployed and is the most widely used.
The “a” standard was introduced next but is not
widely used because it isn’t compatible with “b”
devices. The “g” standard is the newest and the
most versatile; it’s compatible with both “a” and
“b” (see “ ABGs of WLAN ”).
ABGs of WLAN
There are three WLAN
specifications: 802.11b, 802.11a and
802.11g. Therefore, it is important to
make sure your hardware is compatible.
You need to check the letter
following 802.11—that is, b ,
a or g . The “b”
designation came first and is the most
widely used standard. The “a” standard
was next. However, it is not widely
used, primarily because of its
incompatibility with “b” devices.
In 2003 the “g” standard was
introduced, and it is
“backward-compatible” with “b” but not
“a.” The “g” has an effective indoor
range of about 150 feet and almost five
times the transmission output of a “b”
and costs only a few dollars
more—clearly a wise choice for a small
The “g” standard
not only sends digital music as
effectively as “b,” but it also sends
video and increases the rate of file
transfers (text, graphics and digital
photographs) over the wireless network.
The 802.11g is capable of operating
faster than most high-speed Internet
connections. As a result don’t expect to
see any increase when using “g.”
example, we will use equipment designed for the
“g” standard, a Linksys Wireless Access Point
Router, which costs about $70, and two Ethernet
cables, costing about $5 each.
the WLAN takes no more than an hour or so. Follow
along with us as we provide the steps.
Linksys does multiple tasks. As a wireless access
point it creates the connection to your network.
Its four ports also let you connect wired devices.
And as a router it allows the office network
(wireless and wired) to share a high-speed cable
or DSL Internet connection; a dial-up connection
is not recommended because it is too slow.
Since the Linksys provides both wired and
wireless local area network (LAN) access, you also
can plug a desktop computer into it for a wired
Even though our example is
hardware-specific, the guidance we present can be
followed with slight modifications when using
We will prepare
laptop wireless equipment first.
Step 1. Many new laptops come with a NIC
already installed. If your laptop lacks it, you
will need to install one by following the
instructions provided by the vendor. Usually you
can slide the credit-card-sized NIC into the
laptop’s PC-card slot. You’ll also have to load
the wireless software, which will be provided on a
CD-ROM with the NIC, onto the laptop.
Step 2. Plug one end of the first
Ethernet cable into the network port on the
desktop PC. You usually can find the slot on the
back of the computer (it looks like an oversize
Step 3. Plug the other end into any one
of the four ports labeled LAN on the wireless
access point router (see exhibit 1 ,
below). Nearly all new desktop computers have
built-in network ports. If yours is more than a
few years old and doesn’t have them, you may need
to install an Ethernet 10/100 NIC into one of the
Step 4. To allow multiple wired and
wireless users to access your high-speed Internet
connection simultaneously, plug one end of the
second Ethernet cable into your DSL or cable modem
and the other end into the Internet port on the
access point router. Be sure to review the
policies of your Internet service provider (ISP)
to determine the maximum number of concurrent
users allowed on your Internet connection.
Step 5. Plug in the access point router,
wait a few minutes and then turn on the PC and
laptop. To verify connectivity between the PC and
the access point router, check to be sure the tiny
light-emitting diode lights are illuminated;
they’re usually situated on the network port on
the back of your desktop PC. If they aren’t
illuminated, you probably failed to connect the
desktop PC to the access point router or to turn
on the computer or access point router.
The laptop now is configured. Next we prepare
the network devices, which need two pieces of
information to communicate: an Internet protocol
(IP) address on the network (four sets of numbers)
and a subnet mask. Some network devices are
configured automatically, but doing it manually is
not difficult, although, as you’ll see, it
involves many steps.
Step 6. Start with the access point
router; in this case it’s the Linksys. To access
the configuration interface, fire up the PC’s Web
browser and type in the address bar 192.168.1.1
—the default LAN IP address for the Linksys. If
you’re using an alternative brand, follow the
documentation. You will be prompted for a username
and password. Since the Linksys has no default
username, leave this field blank. Type the
password, admin , click on OK and
a Setup Configuration Screen will
appear (see exhibit 2 ).
Step 7. The screen has several parameters
and each must be configured:
Internet Connection Type.
This is the type of configuration you
want for your wide area network (WAN) port. If you
are using a high-speed Internet connection and
have not leased a fixed or static IP address from
your ISP, leave this field at “Automatic
Configuration-DHCP.” Your ISP will automatically
supply the access point’s WAN interface with an IP
address and other configuration parameters.
If you have leased a static IP address, ask
your ISP for the WAN IP address, the subnet mask,
the default gateway and domain name system (DNS)
servers’ IP addresses. Select Static IP and enter
Router Name. Pick an
identifier of your choosing.
Host Name. Call the
ISP’s customer support line to determine whether
you need a Host Name. If not, leave this field
Domain Name. Leave
MTU. This specifies
the largest packet that can be retrieved from the
Internet. Leave this setting at AUTO
Local IP Address.
Leave the default IP address unchanged
unless you have a sound understanding of IP
Subnet Mask. If you
left the IP address unchanged, leave the subnet
mask unchanged at 255.255.255.0 .
DHCP Server. Leave
this setting at Enabled .
Starting IP Address.
We suggest using the default
Starting IP Address .
Maximum Number of DHCP Users.
This shows the maximum number of
computers the DHCP server should assign addresses
to. The default for Linksys is 50, but the maximum
is 253. You may change it to accommodate the
number of computers accessing your network.
Client Lease Time.
We recommend using the default
Client Lease Time .
Static DNS 1–3. The
domain name system is the method the Internet uses
to translate Web site names into IP addresses. You
can enter up to three here if you know the IP
addresses, or your ISP will provide one for you.
Otherwise, leave these fields at 0
and your computers will use your ISP’s
WINS. If you are
using a Windows Internet naming service (a small
office or home probably would not), then fill in
its IP address; otherwise leave the fields at
Time Zone. Set your
Step 8. When completed, the setup screen
should resemble exhibit 2 , above. After
you’ve entered the appropriate data in all of the
required fields, click on Save Settings
at the bottom of the screen.
Step 9. Then click on the
Advanced Routing subtab in the
upper right-hand portion of the setup screen. This
generates a screen ( exhibit 3 ) that
allows you to enable network address translation
(NAT) so that your laptop can communicate on the
Internet using the access point router’s public IP
access point router will substitute its public IP
address for your laptop’s private IP address.
Select Gateway as the
Operating Mode and you will not
need to enter any Static Routing
information. Click on Save
Step 10. Next, click on the
Wireless tab at the top of your
screen ( exhibit 4 ) to set the basic
wireless settings and security features.
The screen has
Wireless Network Mode.
This identifies the networking standards
available to your network. Leave this field at
Mixed so that both 802.11g and
802.11b devices can communicate with your wireless
router. If you have only “g” devices, selecting
802.11g may provide slightly
better performance than setting it at
Wireless Network Name (SSID).
The initials SSID stand for service set
identifier, the public identifier for your access
point. Wireless workstations use the SSID to find
and connect to your WLAN. You can keep the default
SSID at linksys or change it to
another value such as your name. This name will
pop up in the taskbar in Windows XP when your
client computer senses the presence of an access
This is the specific communications
channel your access point will use to broadcast
its radio signals. Use the default channel
Wireless SSID Broadcast.
This determines whether your access point
will broadcast the SSID. Check the Enable
Step 11. Next, click on the
Wireless Security submenu tab
at the top of the screen to open the screen shown
in exhibit 5 . The screen has several
parameters that must be set. They are
Security Mode. Set
it at WEP (wired equivalent
privacy), the most basic standard security mode,
or if you are content with no security, select
Default Transmit Key.
Leave the default key setting at
Choose between the 64- and the 128-bit
encryption key. We suggest using the more secure
Passphrase. Select a
random set of characters of your choosing used to
create a random WEP key. We used cpa .
Keys 1–4. Select any
of four keys generated from the encryption
algorithm. You can choose one (we chose
Key 1 for our example) and
enter it in the wireless NIC configuration
settings for each device. See the installation
instructions provided by your NIC vendor on how to
enter your WEP key on each device.
Step 12. We will now create a password
and configure the administration settings for the
wireless access point router. To do that, click on
the Administration tab so your
screen looks like exhibit 6 .
In the two
fields provided, create a password and re-enter it
to confirm. Keep the password in a safe place; if
you forget it, you must reset the router by
pressing and holding the RESET
button on the back for 10 seconds, which
will change all of your settings back to their
factory default settings.
For increased security, leave
Remote Management at
(Universal Plug and Play) services
Finally, click on Save
Your wireless access
point now is configured and you can close the Web
Step 13. Finally, you have to configure
your laptop to join the network. Go to the
laptop’s Control panel (
Start , Settings
, Control Panel ) and
click on the Network Connections
icon. Then right-click on your wireless
NIC’s icon and select Properties
to open the Wireless Network
Connection Properties screen (
exhibit 7 ).
Wireless Networks to configure
your NIC, which tells your laptop which wireless
network to connect to. If there are no other
access points within range of your laptop, you
will see only your access point’s SSID listed. If
there are multiple access points within range (for
example, your next-door neighbor’s WLAN), you will
need to select your network (in this case it’s
Linksys) in the Available networks
If you enabled WEP on
your wireless access point router, you’ll need to
configure a WEP key on your laptop by selecting
your network ( Linksys , in our
example) in the Available networks
window and clicking on Configure
to produce the Wireless Network
Properties window ( exhibit 8 ).
Step 14. Click on Association
to configure your security parameters as
shown in exhibit 8 and select Open
in the Network Authentication
box. Since we are using WEP
, select WEP in the Data
encryption box and uncheck the
The key is provided for me automatically
box. Enter your WEP key in the
Network key and Confirm
network key boxes. This key was
generated in the access point configuration (see
exhibit 5 ). Since we are using
Key 1 in this example, we will
leave the Key index (
advanced ) field at 1.
If you selected one of the other three
keys, change the Key index field
accordingly. Finally, click on OK
to return to the Wireless Network
Connection Properties screen (
exhibit 7 ). Make sure your network is
first in the Preferred Networks
list (the lower box in exhibit 7 )
and then click on OK . Because
you have enabled your wireless access point to act
as a DHCP server, you will not need to configure
any other network properties. Your laptop now is
To test your WLAN, access the
Internet from your laptop and walk around in your
transmission range. You now can enjoy the
convenience and flexibility of wireless networking
in your office or home.
BRYCE H. PETERSON, master’s
in information systems management (MISM), is an
associate in the risk advisory services practice
at KPMG LLP in Phoenix. His e-mail address is
firstname.lastname@example.org . WILLIAM G. HENINGER,
CPA, PhD, is an assistant professor at Brigham
Young University, Provo, Utah. His e-mail address
. CRAIG J. LINDSTROM, MS, Microsoft Certified
Systems Engineer + Internet (MCSE+I), Cisco
Certified Network Associate (CCNA), is an
assistant professor at Brigham Young University.
His e-mail address is email@example.com
. MARSHALL B. ROMNEY, CPA, CFE, PhD, is the
John and Nancy Hardy Professor of accounting and
information systems at Brigham Young University.
His e-mail address is firstname.lastname@example.org .