Wholesale glossary

PDD (Post-Dial Delay)

Post-Dial Delay (PDD) is the time between the caller finishing dialling and hearing ringback. In wholesale, long or erratic PDD exposes re-origination detours: SIM boxes, OTT gateways and refiled call chains all add hops, and every hop adds delay before the call terminates.

Why it matters

Subscribers abandon after a few seconds of silence, so PDD directly erodes completion rates and perceived quality. For fraud teams, it is a footprint: honest direct routes do not stutter.

What practitioners watch

Benchmark per destination and watch the distribution, not just the mean. PDD spikes on routes sold as direct usually mean indirect handling. Correlate with ACD and ASR drift on the same corridor before escalating.

Related: Voice Transit Observatory · Traffic Management · NER