Rosewill RNX-N400LX - Manual (Page 64)

Wireless Router RNX-N400LX User Manual
many more collisions. By lowering the RTS threshold, there may be fewer collisions, and
performance should improve. Basically, with a faster RTS threshold, the system can
recover from problems faster. RTS packets consume valuable bandwidth, however, so
setting this value too low will limit performance.
12. What is Beacon Interval?
In addition to data frames that carry information from higher layers, 802.11 includes
management and control frames that support data transfer. The beacon frame, which is a
type of management frame, provides the "heartbeat" of a wireless LAN, enabling stations
to establish and maintain communications in an orderly fashion. Beacon Interval
represents the amount of time between beacon transmissions. Before a station enters
power save mode, the station needs the beacon interval to know when to wake up to
receive the beacon (and learn whether there are buffered frames at the access point).
13. What is Preamble Type?
There are two preamble types defined in IEEE 802.11 specification. A long preamble
basically gives the decoder more time to process the preamble. All 802.11 devices
support a long preamble. The short preamble is designed to improve efficiency (for
example, for VoIP systems). The difference between the two is in the Synchronization
field. The long preamble is 128 bits, and the short is 56 bits.
14. What is SSID Broadcast?
Broadcast of SSID is done in access points by the beacon. This announces your access
point (including various bits of information about it) to the wireless world around it. By
disabling that feature, the SSID configured in the client must match the SSID of the
access point. Some wireless devices don't work properly if SSID isn't broadcast (for
example the D-link DWL-120 USB 802.11b adapter). Generally if your client hardware
supports operation with SSID disabled, it's not a bad idea to run that way to enhance
network security. However it's no replacement for WEP, MAC filtering or other
protections.
15. What is Wi-Fi Protected Access (WPA)?
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