ZyXEL Communications P-660HW-TX Manual De Usuario

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P-660HW-Tx v2 Series Support Notes
 
String" passed through the WEP encryption algorithm. Access is denied by 
anyone who does not have an assigned key. WEP comes in 40/64-bit and 
128-bit encryption key lengths. Note, WEP has shown to have fundamental 
flaws in its key generation processing. 
 
3. What is WPA? 
Wi-Fi Protected Access (WPA) is a subset of the IEEE 802.11i security 
specification draft. Key differences between WAP and WEP are user 
authentication and improved data encryption. WAP applies IEEE 802.1x 
Extensible Authentication Protocol (EAP) to authenticate wireless clients using 
an external RADIUS database. You can not use the P-660HW-Tx v2's local 
user database for WPA authentication purpose since the local user database 
uses MD5 EAP which can not to generate keys. 
WPA improves data encryption by using Temporal Key Integrity Protocol 
(TKIP), Message Integrity Check and IEEE 802.1x. Temporal Key Integrity 
Protocol uses 128-bits keys that are dynamically generated and distributed by 
the authentication server. It includes a per-packet key mixing function, a 
Message Integrity Check (MIC) named Michael, an extend initialization vector 
(IV) with sequencing rules and a re-keying mechanism. 
If you do not have an external RADIUS server, you should use WPA-PSK 
(WPA Pre-Share Key) that only requires a single (identical) password entered 
into each access point, wireless gateway and wireless client. As long as the 
passwords match, a client will be granted access to a WLAN. You can refer to 
the User Guide for more information about it. 
 
4. What is the difference between 40-bit and 64-bit WEP? 
40 bit WEP and 64 bit WEP are the same encryption level and can interoperate. 
The lower level of WEP encryption uses a 40 bit (10 Hex character) as "secret 
key" (set by user), and a 24 bit "Initialization Vector" (not under user control) 
(40+24=64). Some vendors refer to this level of WEP as 40 bit, others as 64 
bit. 
 
5. What is a WEP key? 
A WEP key is a user defined string of characters used to encrypt and decrypt 
data. 
 
6. Will 128-bit WEP communicate with 64-bit WEP? 
No. 128-bit WEP will not communicate with 64-bit WEP. Although 128 bit WEP 
also uses a 24 bit Initialization Vector, but it uses a 104 bit as secret key. Users 
need to use the same encryption level in order to make a connection. 
                                     
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