Network Effectiveness Ratio (NER) measures the ability of a network to deliver a call successfully. NER differs from ASR as it does not take into account busy signals, ring -> no answer, and other call failures due to user behavior.
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Note:
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NER % Formula = (completions / attempts_ner) * 100 Formatting: NNN.NN% (same as ASR field).
completions = A SIP Dialog that contains a SIP 200 OK Final Response.
attempts_ner = For Termination Vendor and Origination Customer Trunk Groups, any SIP Final Response outside the range of 400 - 499 is considered as an NER attempt using the B-Leg CDR only. For Termination Customer and Origination Vendor Trunk Groups any SIP Final Response outside the range of 400 - 499 is considered as an NER attempt using the A-Leg CDR only.