Configuring 802.11N - H3C MSR Series Configuration Manual

Step
12. Set the maximum number of
retransmission attempts for
frames larger than the RTS
threshold.
13. Specify the maximum number of
attempts to transmit a frame
shorter than the RTS threshold.
14. Specify the interval for the AP to
hold received packets.
15. Configure collision avoidance

Configuring 802.11n

The following matrix shows the feature and router compatibility:
Featur MSR80
e 0
Available
for
MSR800
802.11n
-W and
MSR800
-10-W.
As the next generation wireless LAN technology, 802.11n supports both 2.4-GHz and 5-GHz bands.
It provides higher throughput by using the following methods:
•
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 work separately with
one acting as the primary channel and the other acting as the secondary channel or working
together as a 40-MHz channel. This provides a simple way of doubling the data rate.
•
Improving channel utilization through the following ways:
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 ns in 802.11a/g to 400 ns. This can increase the data rate by
10 percent.
Command
long-retry threshold count
short-retry threshold count
max-rx-duration interval
•
Specify the request to
send (RTS) threshold
length.
rts-threshold size
•
Specify a collision
avoidance mechanism.
protection-mode
{ cts-to-self | rts-cts }
MSR MSR90 MSR
900 0-E 930
Available
for MSR
930-W,
Availabl
MSR
e for
No 930-W-G
MSR90
U, and
0-E-W.
MSR
930-W-G
T.
16
Remarks
Optional.
By default, the long retry threshold
is 4.
Optional.
By default, the short retry
threshold is 7.
Optional.
By default, the interval is 2000
milliseconds.
•
Optional.
By default, the RTS threshold
is 2346 bytes.
•
Optional.
By default, the collision
avoidance mechanism is
CTS-to-Self.
MSR
MSR 20
20-1X
Available
Available
for
for routers
routers
with a
with a
SIC_WLA
SIC_WLA
N module
N module
that
that
supports
supports
802.11n
802.11n
MSR 30 MSR 50
Available
Available
for
for
routers
routers
with a
with a
SIC_WL
SIC_WLA
AN
N module
module
that
that
supports
supports
802.11n
802.11n