HP a-msr, Руководство по настройке

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To do… Use the command… Remarks
6. Specify the RTS threshold
length.
rts-threshold size
Optional.
By default, the RTS threshold is
2346 bytes.
7. Set the maximum number of
retransmission attempts for
frames larger than the RTS
threshold.
long-retry threshold count
Optional.
By default, the long retry
threshold is 4.
8. Specify the maximum number
of attempts to transmit a frame
shorter than the RTS threshold.
short-retry threshold count
Optional.
By default, the short retry
threshold is 7.
9. Specify the interval for which
a frame received by an AP
can stay in the buffer memory.
max-rx-duration interval
Optional.
By default, the interval for which a
frame received by an AP can stay
in the buffer memory is 2000
milliseconds.
Configuring 802.11n
As the next generation wireless LAN technology, 802.11n supports both 2.4GHz and 5GHz bands. It
provides higher-speed services to customers by using the following methods:
1.
Increasing bandwidth: 802.11n can bond two adjacent 20-MHz channels together to form a 40-MHz
channel. During data forwarding, the two 20-MHz channels can either work separately with one
channel acting as the primary channel and the other acting as the secondary channel; or both can
work together as a 40-MHz channel. This provides a simple way of doubling the data rate.
2.
Improving channel usage through these methods:
 802.11n introduces the A-MPDU frame format. By using only one PHY header, each A-MPDU can
accommodate multiple MPDUs which have their PHY headers removed. This reduces the overhead in
transmission and the number of ACK frames to be used, and improves network throughput.

Similar with MPDU aggregation, multiple MSDU can be aggregated into a single A-MSDU. This
reduces the MAC header overhead and improves MAC layer forwarding efficiency.
 To improve physical layer performance, 802.11n introduces the short GI function, which shortens the GI
interval of 800 us in 802.11a/g to 400 us. This can increase the data rate by 10 percent.
To configure 802.11n:
To do… Use the command… Remarks
1. Enter system view.
system-view —
2. Enter radio interface view.
interface wlan-radio
interface-number
—
3. Enter radio view.
radio radio-number type dot11gn —
4. Specify the bandwidth mode
for the radio.
channel band-width { 20 | 40 }
Optional.
By default, the 802.11gn radio
operates in 20 MHz mode.