SMC Networks SMCWBR11S-N, Руководство пользователя

Страница: 70 / 137

C
HAPTER
7
| Wireless Configuration
Advanced Settings
– 70 –
■
Auto — The unit enables its protection mechanism for 802.11b
clients when they are detected in the network. When 802.11b
clients are not detected, the protection mechanism is disabled.
■
On — Forces the unit to always use protection for 802.11b clients,
whether they are detected in the network or not. Note that enabling
b/g Protection can slow throughput for 802.11g/n clients by as
much as 50%.
■
Off — Forces the unit to never use protection for 802.11b clients.
This prevents 802.11b clients from connecting to the network.
◆
Beacon Interval — The rate at which beacon signals are transmitted
from the access point. The beacon signals allow wireless clients to
maintain contact with the access point. They may also carry power-
management information. (Range: 20-999 TUs; Default: 100 TUs)
◆ Data Beacon Rate (DTIM) — The rate at which stations in sleep
mode must wake up to receive broadcast/multicast transmissions.
Known also as the Delivery Traffic Indication Map (DTIM) interval, it
indicates how often the MAC layer forwards broadcast/multicast traffic,
which is necessary to wake up stations that are using Power Save
mode. The default value of one beacon indicates that the access point
will save all broadcast/multicast frames for the Basic Service Set (BSS)
and forward them after every beacon. Using smaller DTIM intervals
delivers broadcast/multicast frames in a more timely manner, causing
stations in Power Save mode to wake up more often and drain power
faster. Using higher DTIM values reduces the power used by stations in
Power Save mode, but delays the transmission of broadcast/multicast
frames. (Range: 1-255 beacons; Default: 1 beacon)
◆ Fragmentation Threshold – Configures the minimum packet size that
can be fragmented when passing through the access point.
Fragmentation of the PDUs (Package Data Unit) can increase the
reliability of transmissions because it increases the probability of a
successful transmission due to smaller frame size. If there is significant
interference present, or collisions due to high network utilization, try
setting the fragment size to send smaller fragments. This will speed up
the retransmission of smaller frames. However, it is more efficient to
set the fragment size larger if very little or no interference is present
because it requires overhead to send multiple frames. (Range: 256-
2346 bytes; Default: 2346 bytes)
◆ RTS Threshold — Sets the packet size threshold at which a Request to
Send (RTS) signal must be sent to a receiving station prior to the
sending station starting communications. The access point sends RTS
frames to a receiving station to negotiate the sending of a data frame.
After receiving an RTS frame, the station sends a CTS (clear to send)
frame to notify the sending station that it can start sending data.
If the RTS threshold is set to 0, the access point always sends RTS
signals. If set to 2347, the access point never sends RTS signals. If set
to any other value, and the packet size equals or exceeds the RTS