User’s Manual for the NETGEAR Super AG Wireless USB 2.0 Adapter WG111U

Enhanced data privacy

Robust key management

Data origin authentication

Data integrity protection

Starting in August of 2003, all new Wi-Fi certified products had to support WPA and all existing Wi-Fi certified products had one year to comply with the new standard or lose their Wi-Fi certification. NETGEAR has implemented WPA on client and access point products. As of August 2004, all Wi-Fi certified products must support WPA.

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 don't 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.

Wireless Networking Basics

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NETGEAR WG111U user manual How Does WPA Compare to WEP?