Wired Equivalent Privacy (WEP) is a security protocol, specified in the IEEE
Wireless Fidelity (Wi-Fi) standard, 802.11b, that is designed to provide a
wireless local area network (WLAN) with a level of security and privacy
comparable to what is usually expected of a wired LAN.
A wired local area network (LAN) is generally protected by physical security
mechanisms (controlled access to a building, for example) that are effective
for a controlled physical environment, but may be ineffective for WLANs
because radio waves are not necessarily bound by the walls containing the
network.
WEP seeks to establish similar protection to that offered by the wired
network's physical security measures by encrypting data transmitted over the
WLAN. Data encryption protects the vulnerable wireless link between clients
and access points; once this measure has been taken, other typical LAN
security mechanisms such as password protection, end-to-end encryption,
virtual private networks (VPNs), and authentication can be put in place to
ensure privacy.
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