Allen-Bradley 1783-WAPAK9, Руководство пользователя

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Rockwell Automation Publication 1783-UM006A-EN-P - May 2014 249
Configuring Radio Settings Chapter 7
Access Points Send Multicast
and Management Frames at
Highest Basic Rate Access points running recent Cisco IOS versions are transmitting multicast and
management frames at the highest configured basic rate, and is a situation that
can cause reliability problems.
Access points running LWAPP or autonomous IOS can transmit multicast and
management frames at the lowest configured basic rate. This provides for good
coverage at the cell's edge, especially for unacknowledged multicast transmissions
where multicast wireless transmissions fail to be received.
Because multicast frames are not retransmitted at the MAC layer, stations at the
edge of the cell can fail to receive them successfully. If reliable reception is a goal,
then multicasts can be transmitted at a low data rate. If support for high data rate
multicasts is required, then shrink the cell size and to disable all lower data rates.
Depending on your specific requirements, you can take the following action:
•
If you need to transmit the multicast data with the greatest reliability and
if there is no need for great multicast bandwidth, then configure a single
basic rate, one that is low enough to reach the edges of the wireless cells.
•
If you need to transmit the multicast data at a certain data rate to achieve a
certain throughput, then configure that rate as the highest basic rate. You
can also set a lower basic rate for coverage of non-multicast clients.
Beginning in privileged EXEC mode, follow these steps to configure the radio
data rates:
1.
Enter global configuration mode.
configure terminal
2.
Enter interface configuration mode for the radio interface.
The 2.4 GHz radio and 2.4 GHz N radio is radio 0, and the 5 GHz radio
and 5 GHz N radios radio
interface dot11radio {0 | 1}