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How does Packet Loss Concealment improve voice quality?
A. Cisco Packet Loss Concealment technology decreases the voice sampling rate to 10 ms of the voicepayload to smooth gaps in the voice stream.
B. Packet Loss Concealment intelligently analyzes missing packets and generates a reasonablereplacement 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 generatinga reasonable replacement packet to improve the voice quality.
Correct Answer: B
Explanation/Reference:
Explanation: Packet loss concealment is a technology designed to minimize the practical effect of lostpackets in VOIP. PLC mitigates against the effects of packet loss, which is the failure of one or moretransmitted packets to arrive at their destination, by artificially regenerating the packet received prior to thelost one, followed by insertion of the duplicated packet into the gap. The digital value of the dropped packetis estimated by interpolation and an artificially generated packet inserted on that basis.http://www.cisco.com/en/US/partner/tech/tk652/tk698/technologies_tech_note09186a00800f6cf8.shtml
