Quality of Service & Media Handling Flashcards

Which DSCP value is recommended by Cisco and widely used for marking VoIP RTP media traffic to ensure priority queuing?

Answer: EF (Expedited Forwarding, DSCP 46)

EF (Expedited Forwarding, DSCP 46) is the standard DSCP marking for real-time voice RTP traffic, ensuring it receives lowest latency and jitter in network queues.

In AudioCodes Mediant, which parameter configures the DSCP value applied to outgoing RTP packets?

Answer: Premium Service Class Media (PremiumServiceClassMedia)

The PremiumServiceClassMedia parameter sets the DSCP/ToS value stamped on outgoing RTP media packets, enabling QoS prioritization in the network.

What is the primary purpose of a jitter buffer in VoIP media processing?

Answer: To absorb network delay variation and deliver audio packets to the codec at a steady rate

A jitter buffer temporarily stores arriving RTP packets to smooth out variable network delays, providing a steady stream of audio samples to the decoder.

AudioCodes Mediant supports which type of jitter buffer that automatically adjusts its depth based on network conditions?

Answer: Adaptive jitter buffer

The adaptive jitter buffer dynamically increases or decreases its depth in real time based on measured network jitter, balancing latency against packet loss concealment.

What is Packet Loss Concealment (PLC) in AudioCodes media processing?

Answer: An algorithm that synthesizes substitute audio when RTP packets are lost, reducing perceived quality degradation

PLC generates plausible substitute audio frames when packets are missing, minimizing the audible impact of network packet loss on voice quality.

Which MOS (Mean Opinion Score) threshold is typically considered the minimum acceptable quality for enterprise VoIP calls?

Answer: 3.6

A MOS score of 3.6 or above is generally considered the minimum acceptable voice quality threshold for enterprise VoIP deployments.