User`s manual

P-660 Series Support Notes

126

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.

WEP has defensed against this attack. To avoid encrypting two cipher texts with the

same key stream, an Initialisation Vector (IV) is used to augment the shared WEP key

(secret key) and produce a different RC4 key for each packets, the IV is also included

in the package. WEP key (secret key) are available in two types, 64-bits and 128-bits.

Many times you will see them referenced as 40-bits and 104-bits instead. The reason

for this misnomer is that the WEP key (40/104 bits ) is concatenated with the

initialisation vector ( 24 bits ) resulting in a 64/128 bits total key size.

WiFi Protected Access (WPA) is the new security standard adopted by the WiFi

Alliance consortium. WPA uses Temporal Key Integrity Protocol (TKIP). TKIP is

designed to allow WEP to be upgraded. This means that all the main building blocks

of WEP are present, but corrective measures have been added to address security

problems. WPA (TKIP) provides much stronger security than WEP, addressing all the

weaknesses and allowing compatibility and upgrades with older equipment.

802.11 WEP uses IV and base key to generate streaming encryption keys for data

encryption this includes weak IV which could be compromised by a cracker if he have

collected enough transmitted data frame.

TKIP uses IV and base key to hash a new key for every packet