How does Packet Loss Concealment improve voice quality?

A.
Cisco Packet Loss Concealment technology decreases the voice sampling rate to 10 ms of the voice payload to smooth gaps in the voice stream.

B.
Packet Loss Concealment intelligently analyzes missing packets and generates a reasonable replacement packet to improve the voice quality.

C.
Packet Loss Concealment will buffer 20 to 50 ms of a voice stream to minimize lost or out-of- order voice packets.

D.
Packet Loss Concealment will compensate for packet loss rates between 1 and 5 percent by generating a reasonable replacement packet to improve the voice quality.

Explanation:

Packet loss concealment is a technology designed to minimize the practical effect of lost packets in VOIP. PLC mitigates against the effects of packet loss, which is the failure of one or more transmitted packets to arrive at their destination, by artificially regenerating the packet received prior to the lost one, followed by insertion of the duplicated packet into the gap. The digital value of the dropped packet is estimated by interpolation and an artificially generated packet inserted on that basis.

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