User Guide

Table Of Contents
Bridge GUI Guide: Network Configuration
75
3.3.4.9 BSS RTS and Fragmentation Thresholds
The
RTS Threshold allows you to configure the maximum size
of the frames the BSS sends without using the RTS/CTS
protocol. Frame sizes over the specified threshold cause the
BSS to first send a
Request to Send message and then receive
a
Clear to Send message from the destination device before
transmitting the frame.
The
RTS Threshold is measured in bytes. A value of zero (0)
disables the function (the default), or whole values between
1
and
2345 are accepted.
The smaller the
RTS Threshold, the more RTS/CTS traffic is
generated at the expense of data throughput. On large busy
networks, however, RTS/CTS speeds recovery from radio
interference and transmission collisions, and a relatively small
RTS Threshold may be necessary to achieve significant
improvements.
The
Frag. Threshold allows you to configure the maximum size
of the frames the BSS sends whole. Frame sizes larger than
the specified threshold are broken into smaller frames before
they are transmitted. An acknowledgement is sent for each
frame received, and if no acknowledgement is sent the frame is
retransmitted.
The
Frag. Threshold is measured in bytes. A value of zero (0)
disables the function (the default), or whole values between
256 and 2345 are accepted.
Fragmentation becomes an advantage in networks that are:
experiencing collision rates higher than five percent
subject to heavy interference or multipath distortion
serving highly mobile network devices
A relatively small fragmentation threshold results in smaller,
more numerous frames. Smaller frames reduce collisions and
make for more reliable transmissions, but they also use more
bandwidth. A larger fragmentation threshold results in fewer
frames being transmitted and acknowledged and so can
provide for faster throughput, but larger frames can also
decrease the reliability with which transmissions are received.
You can configure RTS and fragmentation thresholds only in
Advanced View.