Atlantis Land A02-RA241-W54 - Manual (Page 82)

WIRELESS ROUTER ADSL2+
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When a data frame exceeds the RTS/CTS value you set (between 0 to 2432 bytes), the
station that wants to transmit this frame must first send an RTS (Request To Send) message
to the AP for permission to send it. The AP then responds with a CTS (Clear to Send)
message to all other stations within its range to notify them to defer their transmission. It also
reserves and confirms with the requesting station the time frame for the requested
transmission.
Stations can send frames smaller than the specified RTS/CTS directly to the AP without the
RTS (Request To Send)/CTS (Clear to Send) handshake.
You should only configure RTS/CTS if the possibility of hidden nodes exists on your network
and the “cost” of resending large frames is more than the extra network overhead involved in
the RTS (Request To Send)/CTS (Clear to Send) handshake.
If the RTS/CTS value is greater than the Fragmentation Threshold value (see next), then the
RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as data frames will
be fragmented before they reach RTS/CTS size.
Fragmentation Threshold
A Fragmentation Threshold is the maximum data fragment size (between 256 and 2432
bytes) that can be sent in the wireless network before the ADSL Router will fragment the
packet into smaller data frames.
A large Fragmentation Threshold is recommended for networks not prone to interference
while you should set a smaller threshold for busy networks or networks that are prone to
interference.
If the Fragmentation Threshold value is smaller than the RTS/CTS value (see previously) you
set then the RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as
data frames will be fragmented before they reach RTS/CTS size.
Levels of Security
Wireless security is vital to your network to protect wireless communication between wireless
stations, access points and the wired network.
The figure below shows the possible wireless security levels on your ADSL Router. The
highest security level relies on EAP (Extensible Authentication Protocol) for authentication
and utilizes dynamic WEP key exchange. It requires interaction with a RADIUS (Remote
Authentication Dial-In User Service) server either on the WAN or your LAN to provide
authentication service for wireless stations.
If you do not enable any wireless security on the ADSL Router, your network is accessible to
any wireless networking device that is within range.
Use the ADSL Router web configurator to configurator to set up your wireless LAN security
settings. Refer to the chapter on using the ADSL Router web configurator to see how to
access the web configurator.