Cisco Systems 7970G, 7971G-GE manual Voice Quality Metrics

Chapter 8 Monitoring the Cisco Unified IP Phone Remotely

Streaming Statistics

		Table 8-5	Streaming Statistics Area Items (continued)
		Item		Description
		Max MOS LQK		Baseline or highest MOS LQK score observed from start of the voice
				stream.
				These codecs provide the following maximum MOS LQK score under
				normal conditions with no frame loss:
				• G.711 gives 4.5
				• G.729 A /AB gives 3.7
		MOS LQK Version		Version of the Cisco proprietary algorithm used to calculate MOS
				LQK scores.
		Cumulative Conceal Ratio		Total number of concealment frames divided by total number of
				speech frames received from start of the voice stream.
		Interval Conceal Ratio		Ratio of concealment frames to speech frames in preceding 3-second
				interval of active speech. If using voice activity detection (VAD), a
				longer interval might be required to accumulate 3 seconds of active
				speech.
		Max Conceal Ratio		Highest interval concealment ratio from start of the voice stream.
		Conceal Secs		Number of seconds that have concealment events (lost frames) from
				the start of the voice stream (includes severely concealed seconds).
		Severely Conceal Secs		Number of seconds that have more than 5 percent concealment events
				(lost frames) from the start of the voice stream.
		Latency1		Estimate of the network latency, expressed in milliseconds. Represents
				a running average of the round-trip delay, measured when RTCP
				receiver report blocks are received.
		Max Jitter		Maximum value of instantaneous jitter, in milliseconds.
		Sender Size		RTP packet size, in milliseconds, for the transmitted stream.
		Sender Reports Received1		Number of times RTCP Sender Reports have been received.
		Sender Report Time		Last time at which an RTCP Sender Report was received.
		Received1
		Rcvr Size		RTP packet size, in milliseconds, for the received stream.
		Rcvr Discarded		RTP packets received from network but discarded from jitter buffers.
		Rcvr Reports Received1		Number of times RTCP Receiver Reports have been received.
		Rcvr Report Time Received1		Last time at which an RTCP Receiver Report was received.
		Voice Quality Metrics
		MOS LQK		Score that is an objective estimate of the mean opinion score (MOS)
				for listening quality (LQK) that rates from 5 (excellent) to 1 (bad).
				This score is based on audible concealment events due to frame loss in
				the preceding 8-second interval of the voice stream. For more
				information, see the “Monitoring the Voice Quality of Calls” section
				on page 9-15.
				Note The MOS LQK score can vary based on the type of codec that
				the Cisco Unified IP Phone uses.
		Avg MOS LQK		Average MOS LQK score observed for the entire voice stream.
	Cisco Unified IP Phone 7970G/7971G-GE Administration Guide for Cisco Unified Communications Manager 7.0
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