Quality Metrics
Ref: ITU-T Recommendation E.425
NER
Network Efficiency Ratio
Direct Telecom Definition • Carrier Industry Standard
A metric measuring carrier network delivery performance by excluding subscriber-induced failures like user busy or no answer.
Technical Definition & Carrier Engineering Standards
Unlike ASR which counts user busy or rejected calls as failures, NER evaluates pure network routing integrity. It considers Answered calls, User Busy, Ringing No Answer, and Terminal Rejections as successful delivery attempts by the carrier network.
Standard Formula / Protocol Algorithm
NER (%) = ((Answered + User Busy + Ringing No Answer + Terminal Reject) / Total Seizures) × 100