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Networking Fundamentals
Wired Equivalent
Privacy (WEP)
a data encryption
protocol that makes
a wireless network
as secure as a wired
network.
Wi-Fi Protected
Access (WPA)
a protocol that
combines the authen-
tication method with
encryption.
802.1x Encryption
The second feature of the 802.1x standard is a way to hide the contents of
network packets. Since the packets are broadcast through the open air, anyone
could capture the packets and inspect the contents using a protocol analyzer
or packet sniffer. A wireless network encryption key is used as part of the
mathematical equation (algorithm) to encrypt data that is to be transmitted over
a wireless network. There will be more about encryption keys in
Chapter 15⎯Network Security.
The packets are encrypted using any one of a number of encryption software
protocols. To make the encryption process unique to a particular network system,
a key is used. You can think of a key as a string of alphanumeric characters that
feed the random character generator used to encrypt the contents of each packet.
The only way to crack the encryption would be to guess or steal the encryption
key. The encryption key can be provided by a security service, manufactured into
a hardware device, or created by the network administrator.
Look at Figure 4-28, which shows the
Association
page of the
WLAN properties
dialog box in Windows XP. Notice that the wireless network has been identifi ed
as WLAN and the data encryption protocol selected is WEP. The acronym WEP
represents Wired Equivalent Privacy. You can see by its name that the Wired
Equivalent Privacy (WEP) protocol is intended to make a wireless network as
secure as a wired network.
Below the
Data encryption
option is an option labeled
Network
key. The
administrator enters the network key into the text box and then enters the key
once more in the option labeled
Confi rm network
key. This procedure is repeated
at other network clients and servers on the wireless network. Each computer
must use the same key to be able to exchange encrypted data with each other.
WPA
The Wi-Fi Alliance introduced Wi-Fi Protected Access (WPA) as an
improvement to overcome the weakness of WEP. You can think of WPA as an
enhancement to WEP. WPA uses the most desirable features of the Temporal
Figure 4-28.
Windows XP
WLAN
properties,
Association
page.
Wireless network
name
Wired Equivalent
Privacy (WEP) has
been chosen for
encryption
The administrator
enters a key here