Call Leg Media Quality Report

[Questo argomento è in fase di elaborazione.]  

Ultima modifica dell'argomento: 2012-08-31

The Call Leg Media Quality Report enables administrators to compare call volumes and call quality for audio calls made across the public switched telephone network (PSTN). This report also gives administrators the ability to focus on specific legs for these calls; for example, you can look only at call volume and quality between the Mediation Server and the PSTN gateway, or only at call volume and quality between the Mediation Server and the A/V Conferencing Server.

Accessing the Call Leg Media Quality Report

The Call Leg Media Quality Report is accessed from the Monitoring Reports home page.

Making the Best Use of the Call Leg Media Quality Report

When you first access the Call Leg Media Quality Report the report is sorted by poor call percentage, with the call leg having the highest percentage of poor calls listed first. In addition to that, however, the report also sorts by call volume: call legs which have more than 30 calls are sorted by poor call percentage, and then sorts the call legs that have 30 calls or fewer, also by call percentage. For example, suppose you have these call legs:

Endpoint 1 Endpoint 2 Call volume Poor call percentage

Server 1

Server 2

100

5.0%

Server 1

Server 3

20

21.0%

Server 1

Server 4

45

17.0%

Server 2

Server 3

10

33.0%

Server 2

Server 4

75

11.0%

Those calls will be sorted like this, with call legs having more than 30 calls sorted first:

Endpoint 1 Endpoint 2 Call volume Poor call percentage

Server 1

Server 4

45

17.0%

Server 2

Server 4

75

11.0%

Server 1

Server 2

100

5.0%

Server 2

Server 3

10

33.0%

Server 1

Server 3

20

21.0%

Filters

Filters provide a way for you to return a more finely-targeted set of data or to view the returned data in different ways. For example, the Call Media Quality Report enables you to filter on such things as call leg or the number of call legs to be returned by the report. In the latter case, you can choose to see the 10, 25, or 50 worst-performing call legs, based on poor call percentage.

The following table lists the filters that you can use with the Call Leg Media Quality Report.

Call Leg Media Quality Report Filters

Name Description

From

Start date/time for the time range. To view data by hours, enter both the start date and time as follows:

7/7/2012 1:00 PM

If you do not enter a start time, the report automatically begins at 12:00 AM on the specified day. To view data by day, enter just the date:

7/7/2012

To view by week or by month, enter a date that falls anywhere within the week or month that you want to view (you do not have to enter the first day of the week or month):

7/3/2012

Weeks always run from Sunday through Saturday.

To

End date/time for the time range. To view data by hours, enter both the end date and time as follows:

7/7/2012 1:00 PM

If you do not enter an end time, the report automatically ends at 12:00 AM on the specified day. To view data by day, enter just the date:

7/7/2012

To view by week or by month, enter a date that falls anywhere within the week or month that you want to view (you do not have to enter the first day of the week or month):

7/3/2012

Weeks always run from Sunday through Saturday.

Top N

Indicates the number of call legs (based on their poor call percentage) to be displayed in the report. For example, if you select 10 then the ten poorest-performing call legs are displayed. Select one of the following:

  • 10

  • 25

  • 50

The default value is 10.

Call Leg

Type of call leg to viewed. Select one of the following:

  • [All]

  • Mediation Server and Gateway

  • Mediation Server and A/V Conferencing Server

The default value is [All].

Metrics

The following table lists the information provided in the Call Leg Media Quality Report.

Metrics for the Call Leg Media Quality Report

Name Can you sort on this item? Description

Endpoint 1

No

Name of the first endpoint in the call.

Endpoint 2

No

Name of the second endpoint in the call.

Call volume

No

Total number of audio calls.

Poor call percentage

Yes

Total number of calls classified as poor. A poor call is any call which at least one of the measured metrics exceeded the allowed value (for example, a call that experienced excessive jitter).

Roundtrip (ms)

Yes

Average amount of (in milliseconds) required for a real-time transport protocol (RTP) packet to travel to another endpoint and then back. Round-trip times of 100 milliseconds or less are considered of acceptable quality.

High round-trip values can be caused by international call routing, a routing misconfiguration, or an overloaded media server. High round-trip times result in difficulties with two-way, real-time audio conversations.

Degradation (MOS)

Yes

Average amount of mean opinion score (MOS) degradation experienced during a call. Degradation values can range from a low of 0.0 to a high of 5.0. A value of 0.5 or less represents acceptable degradation. Historically, mean options scores were calculated by having users rate the quality of a call on a scale of 1-to-5. In Lync Server, the Monitoring Server uses a set of algorithms to predict how users would have rated a call.

High degradation values can be caused by congestion, lack of bandwidth, wireless congestion or interference, or an overloaded media server or endpoint. High degradation results in distorted or lost audio.

Packet loss

Yes

Average rate of RTP packet loss. (Packet loss occurs when RTP packets, a protocol used for transmitting audio and video across the Internet, failed to reach their destination.) High loss rates are generally caused by congestion, lack of bandwidth, wireless congestion or interference, or an overloaded media server. Packet loss typically results in distorted or lost audio.

Jitter

Yes

Average jitter detected between RTP packet arrivals. (Jitter is a measure of the "shakiness" of a call.) High jitter values are typically caused by congestion or an overloaded media server, and result in distorted or lost audio.

Healer concealed ratio

Yes

Average ratio of concealed audio samples to the total to the total number of samples. (A concealed audio sample is a technique used to smooth out the abrupt transition that would usually be caused by dropped network packets.) High values indicate significant levels of loss concealment applied caused by packet loss or jitter, and results in distorted or lost audio.

Healer stretched ratio

Yes

Average ratio of stretched audio samples to the total to the total number of samples. (Stretched audio is audio that has been expanded to help maintain call quality when a dropped network packet has been detected.) High values indicate significant levels of sample stretching caused by jitter, and result in audio sounding robotic or distorted.

Healer compressed ratio

Yes

Average ratio of compressed audio samples to the total number of samples. (Compressed audio is audio that has been compressed to help maintain call quality when a dropped network packet has been detected.) High values indicate significant levels of sample compression caused by jitter, and result in audio sounding accelerated or distorted.

Trend

No

Links to the Server Media Quality Trend Report for the specified call leg.