Netgear WGPS606 사용자 설명서

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Reference Manual for the NETGEAR 54 Mbps Wireless USB Print Server with 4-Port Switch 
Wireless Networking Basics
B-9
Draft 1, 01 Feb 05
Enhanced data privacy
Robust key management
Data origin authentication
Data integrity protection 
Starting August of 2003, all new Wi-Fi certified products had to support WPA. NETGEAR 
implemented WPA on client and access point products and made this available in the second half 
of 2003. 
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. 
How Does WPA Compare to IEEE 802.11i? 
WPA is forward compatible with the IEEE 802.11i security specification. WPA is a subset of 
802.11i and uses certain pieces of the 802.11i were ready to bring to market, such as 802.1x and 
TKIP. The main pieces of 802.11i that are not included in WPA are secure IBSS (Ad-Hoc mode), 
secure fast handoff (for specialized 802.11 VoIP phones), as well as enhanced encryption protocols 
such as AES-CCMP. These features require hardware upgrades and as of January 2005 are now 
becoming widely available.