Internet Speed (Speed Test) Measurement Items and Their Impact on Softphone Call Quality

Question

I am curious about the standard values for the measured items (download / upload / latency / jitter / packet loss) after performing a speed test on the softphone of Matrix Cloud, which can check the network. 
I would like to know what values indicate that the network is slow or has issues.

Answer

I will provide approximate figures for a typical high-speed internet environment.

Among the measurement items, Packet Loss, Latency, and Jitter have the most significant impact on internet access quality and call quality.

In particular, the Jitter value has a considerable effect on call quality. A high Jitter value can negatively affect call quality.

Thank you.