Rev.1 - YML653
www.netcomm.com.au
NP7032 - Wireless LAN PC Card
Page 19
Advanced
The Advanced screen shows the advanced settings of the Wireless LAN Card Utility, and it
includes Preamble Type, Fragmentation Threshold, and RTS / CTS Threshold.
Preamble Type:
The preamble is to limit the packet size of the data transmitted.
It is recommended that the short preamble is selected when the
link quality is bad, thereby preventing wasted time when
resending any lost packets. The default setting is Auto.
Fragmentation Threshold: This option controls the way the transmitting packets will be
fragmented. If a packet is larger, in octets, than the threshold, the
packet will be split up, or fragmented, prior to being transmitted.
Once a packet is
fragmented, if a
portion of the
original packet is
corrupted in transit,
only the corrupted
portion needs to be
retransmitted.
Throughput is
generally lower for
fragmented packets,
however, because the
packet header
consumes RF
bandwidth.
It is recommended to
fragment the packet when the link quality is bad, so as to reduce
the time taken to resend a lost packet.
RTS/CTS Threshold
Defines a threshold for the number of packets that can be
received before the NetComm NP7032 - Wireless LAN PC Card
will issue a Request to Send (RTS) packet. The RTS packet is
used to avoid data collisions on the WLAN. There are some
trade-offs to consider when setting this parameter. A small RTS
threshold will cause RTS packets to be sent more often, thereby
consuming bandwidth and reducing the apparent throughput of
the WLAN. The more often RTS packets are sent, however, the
quicker the WLAN can recover from interference or data
collisions. Refer to the IEEE 802.11b standard for more
information on the RTS/CTS mechanism.
