Controller Based WLANs

Product and Software: This article applies to all Aruba controllers with ArubaOS 2.x and 3.x.

Multicast and broadcast packets are sent in the air without ack. Also, to ensure all stations can receive the packets, they are sent at either basic rate or min tx-rate, whichever is lower. This impacts b/g band because normally the basic rate for b/g band is 1 or 2 Mbps. This is not sufficient for some multicast applications, such as video streaming.

To improve multicast performance, tune the following parameters:
1)    Change the basic rate of b/g band to 5 or 6 Mbps. Remove 1 & 2 Mbps from g-tx-rate as well.
2)    In ArubaOS 3.x, under ssid profile, enable the bc/mc optimization feature as follows:

(test) (config) #wlan ssid-profile default
(test) (SSID Profile "default") #?
...
mcast-rate-opt          Choose the optimal rate for broadcast/multicast frames
...
(test) (SSID Profile "default") # mcast-rate-opt ?
<cr>

The bc/mc optimization feature has been explained in another KB article.