Unified CM call quality grades in Webex
Call Management Records (CMRs) and Call Detail Records (CDRs) are the records that are produced by the Unified CM system. Call quality rating is only possible for endpoints that enable call monitoring records (CMRs). A call might be rated as good, acceptable, or poor based on the information that is contained in a CDR.
The following criteria are considered while assigning grades to calls:
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Concealment—Voice communications, along with all other types of data, are transmitted across IP networks, which have a maximum capacity that is predetermined. In the event that there is congestion, it’s possible that this system will lose data at a higher rate. The audio that is made at the endpoint and utilized to conceal the effect of packet loss in a voice packet stream is referred to as concealment.
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Severely Concealed Seconds (SCS)— The number of seconds that pass before a considerable quantity of concealment (defined as lasting longer than 50 milliseconds) is spotted. If the amount of concealment that is seen is larger than 50 milliseconds, which is approximately equivalent to 5 percent, then the quality of the audio may be diminished.
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Severely Concealed Seconds Ratio (SCSR)—The percentage of the whole call that is devoted to SCS.
SCSR(%)=(SCS/duration)*100
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Long call— A call that is longer than twenty seconds in duration.
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Short call— A call that is terminated within the first twenty seconds.
The SCSR % is used to determine how each call is assessed. Different threshold values are applied to the SCSR % for long calls and short calls respectively. The table that follows presents information on call grades that is based on the SCSR percentage ranges.
Grade |
SCSR Threshold Values |
|
---|---|---|
Long Call SCSR Ranges |
Short Call SCSR Ranges |
|
Good |
Less than 3% |
Less than 20% |
Acceptable |
3%-7% |
20%-30% |
Poor |
Greater than 7% |
Greater than 30% |
If the SCSR for a call that lasts ten seconds is ten percent, then the call is of a satisfactory quality.
When the SCSR for a call that lasts for 120 seconds is 8%, it might be considered to be of low quality.