ZyXEL Communications NBG6503 User Manual page 217

Preamble Type
Preamble is used to signal that data is coming to the receiver. Short and long refer to the length of
the synchronization field in a packet.
Short preamble increases performance as less time sending preamble means more time for sending
data. All IEEE 802.11 compliant wireless adapters support long preamble, but not all support short
preamble.
Use long preamble if you are unsure what preamble mode other wireless devices on the network
support, and to provide more reliable communications in busy wireless networks.
Use short preamble if you are sure all wireless devices on the network support it, and to provide
more efficient communications.
Use the dynamic setting to automatically use short preamble when all wireless devices on the
network support it, otherwise the NBG uses long preamble.
Note: The wireless devices MUST use the same preamble mode in order to communicate.
Wireless Security Overview
Wireless security is vital to your network to protect wireless communication between wireless
clients, access points and the wired network.
Wireless security methods available on the NBG are data encryption, wireless client authentication,
restricting access by device MAC address and hiding the NBG identity.
The following figure shows the relative effectiveness of these wireless security methods available on
your NBG.
Table 82 Wireless Security Levels
SECURITY
LEVEL
Least
Secure
Most Secure
Note: You must enable the same wireless security settings on the NBG and on all wireless
clients that you want to associate with it.
Appendix D Wireless LANs
SECURITY TYPE
Unique SSID (Default)
Unique SSID with Hide SSID Enabled
MAC Address Filtering
WEP Encryption
IEEE802.1x EAP with RADIUS Server Authentication
Wi-Fi Protected Access (WPA)
WPA2
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