Note:
ASR = (sum of answered calls) / (sum of call attempts) * 100
The answer-seizure ratio (ASR) measures network quality and call success rates. The ASR is the number of answered calls (i.e. the number of seizures resulting in an answer) divided by the total number of seizures times 100. The actual ASR calculation is based on CDRs.
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For reporting purposes, call attempts from Termination Customer Trunk Groups only count towards the A Leg CDR. Termination Vendor Trunk Groups only count towards the B Leg plus the A Leg with a 200OK.
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Example
A SIP Invite comes in a Termination Customer (A Leg) Trunk Group, B Leg call attempt to Vendor X fails, B Leg call attempt Vendor Y fails, B Leg call attempt to Vendor Z succeeds (e.g. a SIP 200OK response is provided). This Call flow generates one A leg CDR and two B leg CDRs.
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