HP M210 Configuration And Administration Manual page 58

Note
If SGI is enabled on the M210 but a wireless client does not support SGI, the client will be able
to communicate with the M210 at a data rate that is about 10% slower than SGI-enabled
clients.
Select one of the following options:
•
Yes (default): AP transmits data using a 400 ns guard interval when communicating with
clients that also support the short guard interval.
•
No: The AP transmits data using an 800 ns guard interval.
STBC mode
This setting is available only if the selected radio mode includes 802.1 1n.
Space Time Block Coding (STBC) is an 802.1 1n technique that improves the reliability of data
transmissions. The data stream is transmitted on multiple antennas so the receiving system has a
better chance of detecting at least one of the data streams. Enabling STBC results in a lower
but more stable throughput.
Select one of the following options:
•
On: AP transmits the same data stream on multiple antennas at the same time.
•
Off: The AP does not transmit the same data on multiple antennas.
Protection
The protection feature provides rules to guarantee that 802.1 1n and 802.1 1g transmissions do
not cause interference with legacy stations or applications. By default, these protection
mechanisms are enabled (Auto). With protection enabled, protection mechanisms will be
invoked if legacy devices are within range of the AP.
You can disable these protection mechanisms (Off). When protection is off, however, legacy
clients or APs within range can be affected by 802.1 1n transmissions. Protection is also
available when the mode is 802.1 1b/g. When protection is enabled in this mode, it protects
802.1 1b clients and APs from 802.1 1g transmissions.
Note
This setting does not affect the ability of the client to associate with the AP.
Beacon interval
Beacon frames are transmitted by an AP at regular intervals to announce the existence of the
wireless network. The default behavior is to send a beacon frame once every 100 milliseconds
(10 per second).
Enter a value from 20 to 2000 milliseconds.
DTIM period
Specify a DTIM period from 1 to 255 beacons.
The Delivery Traffic Information Map (DTIM) message is an element included in some beacon
frames. It indicates which wireless clients, currently sleeping in low-power mode, have data
buffered on the AP awaiting pickup.
The DTIM period you specify indicates how often the clients served by this AP should check for
buffered data still on the AP awaiting pickup.
58 Wireless configuration