Cisco 8831NR Administration Manual page 145

Troubleshooting and Maintenance
• Security
You can reset a conference phone at any time after the conference phone has started up.
To reset the device, press Apps > Admin Settings > Reset Settings, then select one of the following settings
to reset back to factory defaults:
• All
• Network
• Security
Quality Report Tool
The Quality Report Tool (QRT) is a voice quality and general problem-reporting tool for the conference
phone. The QRT feature is installed as part of Cisco Unified Communications Manager.
You can configure users' conference phones with QRT. When you do so, users can report problems with
conference phone calls by pressing the QRT softkey. This softkey is available only when the conference phone
is in the Connected, Connected Conference, Connected Transfer, or OnHook states.
When a user presses the QRT softkey, a list of problem categories appears. The user selects the appropriate
problem category and this feedback is logged in an XML file. Actual information logged depends on the user
selection and whether the destination device is a conference phone.
For more information about using QRT, see the Cisco Unified Communications Manager Features and
Services Guide.
Voice Quality Monitoring
To measure the voice quality of calls that are sent and received within the network, conference phones use
these statistical metrics that are based on concealment events. The DSP plays concealment frames to mask
frame loss in the voice packet stream.
• Concealment Ratio metrics: Show the ratio of concealment frames over total speech frames. An interval
• Concealed Second metrics: Show the number of seconds in which the DSP plays concealment frames
• MOS-LQK metrics: Use a numeric score to estimate the relative voice listening quality. The conference
MOS LQK scores are produced by a Cisco proprietary algorithm that is an implementation of P.VTQ, an ITU
provisional standard.
conceal ratio is calculated every 3 seconds.
due to lost frames. A severely "concealed second" is a second in which the DSP plays more than five
percent concealment frames.
phone calculates the mean opinion score (MOS) for listening quality (LQK) based audible concealment
events due to frame loss in the preceding 8 seconds, and includes perceptual weighting factors such as
codec type and frame size.
Cisco Unified IP Conference Phone 8831 and 8831NR Administration Guide
Quality Report Tool
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