Connection Quality Indicator – CBA Live Assist Help Center

Introduction

When you create a client application based on the SDK you can implement connection quality callbacks. During a call the application can receive callbacks on the quality of the network.
The Call object has a new method to support this:

/**
* Callback for when the quality of the connection from the remote end
* of the call changes.
*
* @param connectionQuality a number between 0 and 100 representing the
* current connection quality, where 100 is perfect
*/
onConnectionQualityChanged: function(connectionQuality) {
console.log("onConnectionQualityChanged: The remote stream
quality is now: " + connectionQuality);
}

Mechanism

The connection quality call-back returns a computed quality score out of 100.
Currently connection-quality is computed using the measured packet-loss on the received audio stream:
Calculation is based on standard E-model quality measure.

R=||100.0 - 95.0xloss/loss+10||

The SDK starts collecting metrics as soon as the remote media stream is received. The metrics are collected every 5s, so the 1st quality callback will fire roughly 5s after the remote media stream callback has been established.
The callback will then be fired every time a different quality value is calculated, so if the quality is perfect then there will be an initial quality callback with a value of 100 (after 5s), and then no further callback until the quality degrades.
Audio Quality is non-linear: 2% more loss does not mean audio is 2% worse
Summary of our testing:
Loss = 0% --- R = 100 (best it can be)
Loss = 4% --- R = 73 (poor but serviceable audio)
Loss = 8% --- R = 58 (audio unserviceable)