ASR, ACD and PDD: Reading VoIP Route Quality Metrics Honestly

Definitions

• ASR (Answer Seizure Ratio) = answered calls ÷ call attempts.
• ACD (Average Call Duration) = connected minutes ÷ answered calls.
• PDD (Post-Dial Delay) = time between sending the call and hearing ringing or answer.
• NER (Network Effectiveness Ratio) — like ASR but counts busy and no-answer as network successes; useful to separate route faults from called-party behaviour.

Why the numbers mislead

• ASR depends on your list quality, calling hours and consent rates as much as the route — the same route can show very different ASR for two customers.
• Very high ASR with very short ACD can mean false answer supervision: calls are marked answered when they reached a recording or ringback.
• Short tests are noisy. Compare routes on the same numbers, at the same time of day, with enough calls to see a pattern.

A fair comparison

• Split one list randomly across the routes you are comparing.
• Run at the same time windows and pacing.
• Compare ASR, ACD, PDD, audio complaints and caller-ID presentation together, not one metric alone.

At CallCenterBoost

No ASR, ACD or PDD figure is published or guaranteed for any route. Route quality is something you verify on your own traffic through route testing.