Which QoS mechanisms can you use on a converged network to improve VoIP quality?
(Select three)

A.
The use of a queuing method that will give VoIP traffic strict priority over other traffic.

B.
The use of RTP header compression for the VoIP traffic.

C.
The proper classification and marking of the traffic as close to the source as possible.

D.
The use of 802.1QinQ trunking for VoIP traffic.

E.
The use of WRED.

Explanation:
In order to optimize the quality of VOIP calls, QoS should be implemented to ensure that
VOIP traffic is prioritized over other traffic types.
By providing a strict queue for VOIP traffic, you will ensure that voice calls take precedence
over the other traffic types.
In order to properly provide for QoS across the network, the voice traffic should be marked to
give priority as close to the source as possible. This will ensure that the traffic is prioritized
end to end.
Finally, WRED (Weighted Random Early Detection) could be configured to prevent
congestion. WRED can be used to selectively drop less important traffic types, instead of
dropping the voice packets when links become busy.
Incorrect Answers:
B: Compression can be used to lower the bandwidth required to transmit VOIP calls, but it
will not help with improving the voice quality. In general, compression of any kind lowers the
quality of VOIP.
D)
The trunking method used will have no bearing on the VOIP quality.