A corporation has a Cisco Unified Wireless Network that has been deployed for voice coverage. The wireless data rates have been tuned to mandatory rates of 18 Mbps and 36 Mbps. Some wireless clients have been experiencing drops streaming multicast video while moving throughout the building. What is the cause of the drop in video?
A. Clients are maintaining a 12Mbps rate and cannot receive the stream at 18Mbps.
B. Clients are not roaming due to coverage. This is causing the multicast data to drop due to the client re-associating often.
C. Clients are roaming at lower data rates and are not maintaining 36Mbps connectivity.
D. Clients are connected at 18Mbps; however, other clients are connecting at 12Mbps and are causing the multicast video to degrade.
https://www.cisco.com/c/en/us/support/docs/wireless/5500-series-wireless-controllers/116057-site-survey-guidelines-wlan-00.html#anc33
In general, Multicast/Broadcast frames are sent at the highest mandatory (basic) data rate. There is an exception if there are current associated clients that transmit at a rate lower than the highest mandatory rate. In this situation, the AP sends Multicast/Broadcast frames at the highest mandatory rate that is below or equal to all of the current client transmission rates.
For example, the highest mandatory rate is 24 Mbps and lowest mandatory is set to six (6) Mbps. If all clients on that BSSID transmit at 24 Mbps or higher, then use 24 Mbps to transmit multicast. But, if any one client rate shifts down to six (6) Mbps, then the transmission occurs at six (6) Mbps. Otherwise that client cannot receive it.
So, I think it’s not C.
Agree with Marcos, B is most possible.
Correct Answer is D
B for me