Important Notes on Measurements
This section provides some important notes on the calculation of certain groups of performance monitoring parameters.
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A minimum of 5 calls since device startup is required to calculate current performance monitoring parameters. |
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A minimum of 5 calls in the last interval is required to calculate history performance monitoring parameters. |
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For devices in High Availability (HA) mode - upon a switchover, the value of the sipRecSessionsCount performance monitoring parameters are reset ("null"). |
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Average Call Duration (ACD), Answer Seizure Ratio (ASR), Network Effectiveness Ratio (NER), and Post Dial Delay (PDD) statistics:
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For devices in HA mode - upon a switchover, the value of these performance monitoring parameters are reset ("null"). |
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A minimum of 10 calls is required in the last 5 minutes to calculate these realtime performance monitoring parameters. |
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A minimum of 10 calls is required in the last interval to calculate these history performance monitoring parameters. |
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(ASR, NER and PDD only) When these performance monitoring parameters are per entity (e.g., IP Group or SRD), only outbound calls to these entities are considered in the calculation. |
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When these performance monitoring parameters are per entity (e.g., IP Group or SRD), both inbound and outbound calls to these entities are considered in the calculation. |
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Only connected calls are considered for calculation. |
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The default value is "null" (if there are less than 10 calls per last collection interval) because 0 means all calls ended immediately and can cause important routing decisions accordingly. |
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These statistics are updated once every minute. |
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Example of how ASR statistics is calculated: |
The calculation of real-time weighted NER performance monitoring is a weighted average of 5 values ("cell values"). Each "cell value" represents the ratio of answered calls/seizure calls for 1 minute. If we assume that the current time is 15:06:
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Cell
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1
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2
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3
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4
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5
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Time
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15:00 -15:01
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15:01 -15:02
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15:03 -15:04
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15:04 -15:05
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15:05 -15:06
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Ratio
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70%
40 seizured calls
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80%
15 seizured calls
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100%
25 seizured calls
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100%
10 seizured calls
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100%
10 seizured calls
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Therefore, ASR PMs value = (70*40+80*15+100*25+100*10+100*10)/(100 calls) = 85%
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Active Sessions statistics (activeSessions, activeSessionsAvg, activeSessionsMax):
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These performance monitoring parameters report a "null" value if both SDR syslog and SDR local storage options are disabled. The historical intervals where SDR is disabled are reported as "null" as well. Sessions started before enabling SDR are not included in the report. |
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Short calls statistics (shortCallsCounter):
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A minimum of 10 calls is required in the last interval to calculate this history performance monitoring parameter. |
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The call is considered a short call if its duration is less than or equal to the value configured by the [ShortCallSeconds] parameter. |
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Long calls statistics (longCallsCounter):
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A minimum of 10 calls is required in the last interval to calculate this history performance monitoring parameter. |
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The call is considered a long call if its duration is greater than or equal to the value configured by the [LongCallMinutes] parameter. |
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User-Defined Failures statistics (e.g., userDefinedFailuresIn):
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These performance monitoring parameters only count original responses; not responses that you may have manipulated using Message Manipulation rules. For example, if you have configured a user-defined performance monitoring parameter to count SIP 408 responses and you have a Message Manipulation rule that changes SIP 403 responses into SIP 408, the count excludes these manipulated responses. |
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These performance monitoring parameters consider incoming SIP CANCEL messages as SIP 487 responses. |
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These performance monitoring parameters don't count SIP BYE requests. |
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To save memory resources, these performance monitoring parameters are not initialized until you have configured the first user-defined performance parameter (in the User Defined Failure PM table). If you delete all configured user-defined parameters, all their performance monitoring values are also removed from memory (i.e., "element not found" if you try searching for them). If you add, for example, "User-Defined1", then "User-Defined2" but then modify "User-Defined2"'s condition or delete it and then add it again, "User-Defined2"’s value is preserved. |
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High-Availability systems: CALL_START and CALL_CONNECT counter Performance Monitoring parameters (real-time and history), which are already counted (incremented) on the Active device are not incremented again when they are recovered after an HA switchover. |