Introduction To Wpa; Wep Encryption; Rts/Cts - ZyXEL Communications G-4100 V2 User Manual

G-4100 v2 User's Guide
Adjacent channels partially overlap however. To avoid interference due to overlap, your AP
should be on a channel at least five channels away from a channel that an adjacent AP is using.
For example, if your region has 11 channels and an adjacent AP is using channel 1, then you
need to select a channel between 6 and 11.

23.2.4 Introduction to WPA

Wi-Fi Protected Access (WPA) is a subset of the IEEE 802.11i standard. Key differences
between WPA and WEP are user authentication and improved data encryption. WPA applies
IEEE 802.1x and Extensible Authentication Protocol (EAP) to authenticate wireless clients
using an external RADIUS database. You cannot use the ZyXEL Device's built-in
authentication for WPA authentication purposes since the built-in authentication uses EAP-
MD5, which cannot be used to generate keys.
WPA improves data encryption by using Temporal Key Integrity Protocol (TKIP), Message
Integrity Check (MIC) and IEEE 802.1x. Temporal Key Integrity Protocol (TKIP) uses 128-bit
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
extended initialization vector (IV) with sequencing rules, and a re-keying mechanism.

23.2.5 WEP Encryption

WEP (Wired Equivalent Privacy) encrypts data frames before transmitting over the wireless
network. WEP encryption scrambles the data transmitted between the wireless stations and the
access points to keep network communications private. It encrypts unicast and multicast
communications in a network. Both the wireless stations and the access points must use the
same WEP key for data encryption and decryption.
WEP degrades performance.

23.2.6 RTS/CTS

A hidden node occurs when two stations are within range of the same access point, but are not
within range of each other. The following figure illustrates a hidden node. Both stations (STA)
are within range of the access point (AP) or wireless gateway, but out-of-range of each other,
so they cannot "hear" each other, that is they do not know if the channel is currently being
used. Therefore, they are considered hidden from each other.
176 Chapter 23 Wireless LAN