Voice over LTE

Rich MOS


Qrystal 5.0 provides a methodology for learning about the complex relationships between network events and flow quality by drawing rich representations of them. It combines highly detailed information from media and control plane.

  • To precisely monitor VoLTE quality Qrystal collects R-Rating values for each 5-second time slice on the media plane – all streams, both directions. Those R-ratings are translated into precise MOS values (reflecting the use of wideband or narrowband codecs).


What you get is a very rich picture of voice and video quality: the probably most detailed information available about network performance and user experience.


That is, why we call those MOS values Rich MOS. Rich MOS value are interpreted against the more detailed R-factor scale and against the background of 400 metrics we collect with every 5-second time slice.

  • The finished picture sparks an immediate understanding.
  • On the first view you get the real-time essence of media quality.
  • If an alarm is triggered, it possible to get down to root cause with a few clicks.