Wireless Application Notes; Wireless Introduction; Wep Configuration (Wired Equivalent Privacy) Introduction - ZyXEL Communications P-2812HNU-51c Support Notes

P-2812HNU-51C Support Notes

Wireless Application Notes

Wireless Introduction

WEP Configuration (Wired Equivalent Privacy) Introduction

The 802.11 standard describes the communication that occurs in the wireless LANs.
The Wired Equivalent Privacy (WEP) algorithm is used to protect wireless
communication from eavesdropping, because the wireless transmissions are easier
to intercept than transmissions over wired networks, and wireless is a shared
medium. Everything that is transmitted or received over a wireless network can be
intercepted.
The WEP relies on a secret key that is shared between a mobile station (e.g. a laptop
with a wireless Ethernet card) and an access point (i.e. a base station). The secret key
is used to encrypt packets before they are transmitted, and an integrity check is used
to ensure that packages are not modified during the transition. The standard does
not discuss how the shared key is established. In practice, most installations use a
single key that is shared between all mobile stations and access points APs.
The WEP employs the key encryption algorithm, Ron's Code 4 Pseudo Random
Number Generator (RC4 PRNG). The same key is used to encrypt and decrypt the
data.
The WEP has defenses against this attack. To avoid encrypting two cipher texts with
the same key stream, an Initialization Vector (IV) is used to augment the shared WEP
key (secret key) and produce a different RC4 key for each packet. The IV is also
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