Netgear WGU624 Guide D’Exploitation

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Reference Manual for the Double 108 Mbps Wireless Firewall Router WGU624
Wireless Networking Basics
D-9
M-10153-01
The IEEE introduced the WEP as an optional security measure to secure 802.11b (Wi-Fi) WLANs, 
but inherent weaknesses in the standard soon became obvious. In response to this situation, the 
Wi-Fi Alliance announced a new security architecture in October 2002 that remedies the 
shortcomings of WEP. This standard, formerly known as Safe Secure Network (SSN), is designed 
to work with existing 802.11 products and offers forward compatibility with 802.11i, the new 
wireless security architecture being defined in the IEEE. 
WPA offers the following benefits: 
Enhanced data privacy
Robust key management
Data origin authentication
Data integrity protection 
How Does WPA Compare to WEP?
WEP is a data encryption method and is not intended as a user authentication mechanism. WPA 
user authentication is implemented using 802.1x and the Extensible Authentication Protocol 
(EAP). Support for 802.1x authentication is required in WPA. In the 802.11 standard, 802.1x 
authentication was optional. For details on EAP specifically, refer to IETF's RFC 2284. 
With 802.11 WEP, all access points and client wireless adapters on a particular wireless LAN must 
use the same encryption key. A major problem with the 802.11 standard is that the keys are 
cumbersome to change. If you do not update the WEP keys often, an unauthorized person with a 
sniffing tool can monitor your network for less than a day and decode the encrypted messages. 
Products based on the 802.11 standard alone offer system administrators no effective method to 
update the keys.
For 802.11, WEP encryption is optional. For WPA, encryption using Temporal Key Integrity 
Protocol (TKIP) is required. TKIP replaces WEP with a new encryption algorithm that is stronger 
than the WEP algorithm, but that uses the calculation facilities present on existing wireless devices 
to perform encryption operations. TKIP provides important data encryption enhancements 
including a per-packet key mixing function, a message integrity check (MIC) named Michael, an 
extended initialization vector (IV) with sequencing rules, and a re-keying mechanism. Through 
these enhancements, TKIP addresses all of known WEP vulnerabilities.