Advanced Setup - CNET CWR-500 User Manual

6.1 Advanced setup

These settings are only for more technically advanced users who have a sufficient
knowledge about wireless LAN. These settings should not be changed unless you
know what effect the changes will have on your device.
Authentication Type: Open system or share key.
Open system: The default authentication service that simply announces the
desire to associate with another station or access point. A station can authenticate
with any other station or access point using open system authentication if the
receiving station designates open system authentication.
Share key: The optional authentication that involves a more rigorous exchange
of frames, ensuring that the requesting station is authentic. For a station to use
shared key authentication, it must implement WEP.
Fragment Threshold: Fragment threshold defines a threshold above, which the
wireless packet will be split up, or fragmented. For a fragmented packet, if
transmission of part of it were to be interfered with, only the portion that was
successfully transmitted would need to be resent. Throughput will generally be lower
for fragmented packets, since the fixed packet overhead consumes a higher portion of
the RF bandwidth.
RTS Threshold: The RTS threshold sets an upper threshold at which point the device
will issue an RTS packet. The RTS (Request to Send) packet is used for the purpose of
avoiding data collisions on the wireless LAN. There are several trade offs to consider
when setting this parameter. Setting this parameter to a small value causes RTS
packets to be sent more often, consuming more of the available bandwidth, therefore
reducing the apparent throughput of other network packets. However, the more often
RTS packets are sent, the quicker the system can recover from interference or
collisions. Refer to the IEEE 802.11 standard for more information on the RTS/CTS
mechanism.
Beacon Interval: This 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).
Data Rate: The actual rate at which data transmission occurs varies according to the
strength of signal transmitting the data. Distance and environment can affect the
strength of the signal that can be transmitted and received. The signal strength
determines the type of modulation technique used to encode data, which affects the
volume of data (i.e. the number of bits) that can be encoded in a given space of the
carrier signal. The IEEE 802.11b standard specifies that WLAN devices adapt the rate