130
6.2.2 Wireless Advanced Setup
To achieve optimal wireless performance, it is necessary to tweak advance setting per requirements properly, not
necessary higher the better or lower.
The administrator can change the RTS threshold and fragmentation threshold settings for the system. Please click on
Wireless -> Advanced Setup
and follow the below setting.
Short Slot :
By default, it’s “
Enable
”
for
educing the slot time from the standard
20
microseconds
to the
9
microsecond
short slot time
Slot time is the amount of time a device waits after a collision before retransmitting a packet. Reducing the slot time
decreases the overall back-off, which increases throughput. Back-off, which is a multiple of the slot time, is the
random length of time a station waits before sending a packet on the LAN. For a sender and receiver own right of the
channel the shorter slot time help manage shorter wait time to re-transmit from collision because of hidden wireless
clients or other causes. When collision sources can be removed sooner and other senders attempting to send are
listening the channel(CSMA/CA) the owner of the channel should continue ownership and finish their transmission
and release the channel. Then, following ownership of the channel will be sooner for the new pair due to shorter slot
time. However, when long duration of existing collision sources and shorter slot time exist the owners might
experience subsequent collisions. When adjustment to longer slot time can’t improve performance then RTS/CTS
could supplement and help improve performance.
Extra Slot Time :
Slot time is in the range of
1~255
and set in unit of
microsecond
. The default value is
9
microsecond.
When you enable Short Slot and set Extra Slot time to “10”, the actual Slot Time=9+10 us.
When you disable Short Slot and set Extra Slot time to “10”, the actual Slot Time=20+10 us.
