BOOT CAMP 286 (05/08/03)
Wireless Networking part 6
We’ve reached the final instalment in this short series on
wireless networking and this week’s topics are security and using Wi-Fi
Wireless networks are vulnerable because Wi-Fi components are
sold with their encryption systems switched off. Readily available software utilities like
‘packet sniffers’ can reveal PC and network ‘identities’, which is about the
only protection an unencrypted wireless network has.
Wi-Fi uses the WEP or Wired Equivalent Privacy encryption
system, which implies that it provides the same degree of security as a
conventional cabled network. In fact WEP has been shown to have a number of
loopholes but it is sufficiently robust for the majority of home and small
office users, moreover it is very easy to setup and use and should have no
impact on performance.
Enabling WEP is easy; the first step is to generate a ‘key’,
which is an alphanumeric code that each of the Wi-Fi Client PCs needs to access
the wireless router and unscramble data The key generator is usually found on
the wireless router’s setup menu, which is usually accessed from a web browser
on one of the PCs in the network.
The procedure varies but usually all you have to do is open
Internet Explorer and enter the wireless router’s IP in the Address window. It
usually looks something like http://192.168.000.100
(the last three digits may be different); a password dialogue box should open,
key in your PIN and select the WEP or Encryption menu. There you should find the
code generator box, on most models you have to enter a ‘passphrase’. This is a
random code, made up by you, consisting of the numbers 0 to 9 and letters A to
F. The length of the passphrase determines the level of encryption; typically a
10-character passphrase is needed for basic 64-bit encryption, whilst a
26-character passphrase is used for more secure 128-bit encryption. Click the ‘Create’ button and one or more
keys will be displayed. Note them down, save the changes and exit the
Next go to the Wi-Fi adaptor configuration utility on one of
your Client PCs and enable 64 or 128-bit encryption then enter the key. Exit the
dialogue box and reboot and usually that’s all there is to it, though as we’ve
said before, whenever you make any changes to network configuration it’s a good
idea to shut down and reboot the whole system, starting with the router.
Wireless ‘hotspots’ are springing up all over the place, in
hotels, airport lounges, coffee shops, exhibitions and conference centres.
Hotspots are public access points from where you can surf the Internet or send
and receive emails from your Wi-Fi enabled laptop or portable PC.
Some Hotspots are free to use others require the user to sign
up or subscribe to the service and pay a flat fee or for the time they are
online or the amount of data they download. In short it is all very new and a
bit chaotic but if you are out and about with your Wi-Fi laptop it’s worth
giving it a try.
First find your hotspot. This may require a little research,
try visiting the web sites of any establishments you’ll be visiting; ask around
in hotels and airport lounges and keep an eye open for fellow wireless surfers.
Some Hotspots are clearly signposted and you might strike lucky and find a
helpful member of staff who can explain how the system works (but don’t bank on
If you suspect there’s a hotspot nearby it’s worth switching
on your laptop and opening your Wi-Fi configuration utility (see alto Tip of the
Week). Most have signal strength meter or ‘Site Survey’ tool, which show if
there is any active wireless networks in the vicinity and displays their SSID
(Service Set Identifier). Open your web browser and see if it logs on to the
hotspot’s welcome or signup page.
If not you may need to make some changes to your Wi-Fi
adaptor and PC in order to get a connection. In some cases you will need to know
the Hotspot’s SSID which has to be entered or selected in the wireless adaptor’s
configuration utility. WEP encryption should be disabled and make sure the
adaptor is set for Infrastructure mode. If you are using Windows 9x (98/SE/ME),
in Control Panel select Networking then the TCP/IP properties for your wireless
adaptor. On the IP tab ensure that it is set to ‘Obtain IP address
One final low-tech tip for aspiring ‘hotspotters’; make sure
your portable PC’s batteries are fully charged, or carry a spare. Web browsing
and wireless adaptors will increase your laptop’s power consumption and can
significantly reduce running times.
Next week – Shareware and Freeware
Common network configuration whereby all data passes through
a central exchange or ‘router’.
Internet Protocol – unique numeric code or ‘address’ assigned
to all devices connected to a network or the Internet
Software tool used to monitor, capture and decode data moving
around a network
TIP OF THE WEEK
Finding a Wi-Fi Hotspot and configuring your PC to access it
can be a time consuming business so this freeware utility, from leading Hotspot
operator Boingo, is well worth having. It’s a collection of tools and includes a
wireless network ‘sniffer’ that shows details any nearby active networks, plus a
configuration manager for storing the settings for several hotspots. It works
with most popular Wi-Fi adaptors but check first on the compatibility page,
which you’ll find, along with the link to the software download at: www.boingo.com/