Understanding Spearline Post Dial Delay (PDD)

Nobody likes delays. In the modern world of instant messaging, fast broadband speeds, and direct video conferencing, the last thing anyone wants is to wait. 

So what happens when a customer is waiting to contact your organization via their phone, and they don’t hear a ring tone until ten or twenty seconds after dialing? Well, for one thing, they can get extremely confused listening to that awkward silence.

This moment that a customer is impatiently waiting in and getting annoyed by is known as post dial delay (PDD).

What is post dial delay (PDD) ? 

The standard definition of PDD can be defined as: “the time or delay that occurs from the time a number has been dialed, until the caller or called party hears ringing.”

Bandwidth, a leading US carrier who offers communication APIs that allow companies to embed voice calling and messaging capability into their applications, says that “PDD occurs because each carrier can take a few seconds to acknowledge their ability to complete the call.”

Most carriers in the telecommunications industry consider anything under seven seconds as an acceptable amount of PDD, with most not troubleshooting it. Seven seconds might seem like nothing on paper, but for someone waiting on an instantaneous call, such as a call to an emergency number, this can seem like an eternity. 

The challenge for our customers

Unlike a standard call between two people, where your phone may ring before answering, our customers’ numbers are generally configured to answer straight away. An IVR welcome message is presented to the caller. 

This means that PDD in the strictest of definition, does not meet our customers’ needs, and any ringtones provided are often comfort ringtones designed to mask longer connection times. 

For this reason, Spearline calculates PDD a little differently in order to meet our customers’ requirements.

How does Spearline measure post dial delay?

Spearline replicates the exact flow your customer experiences when they place a call. Spearline places out a number of test calls, which are set to answer automatically. This means, in a typical test call flow, ringing won’t be heard.

To sum it up, the Spearline PDD test is a “call answer time” metric that includes any delay added by intermediary networks. The PDD test detects delays that cannot be identified by using the industry-standard PDD calculation.

If you would like to find out more about how the Spearline PDD calculation works, please take a look at our post dial delay test type page.

New to Spearline?

Spearline is a technology company that proactively tests toll, toll-free and premium-rate numbers for audio quality and connectivity globally. We support business sectors, such as contact centers, conferencing services, and other applications, in successfully connecting with their customers. If you are interested in benefiting from our platform, please get in touch with us.

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