Plan requirement
| Subscription | Any plan |
Our status page shows a call quality score from 1 to 5. Here is what the number means and why it never reaches 5.
What MOS is
MOS stands for Mean Opinion Score. It rates how a call sounded on a scale from 1 to 5. Nobody is asked to listen and score: the figure is calculated from packet loss, jitter and delay using the E-model in the telephony standard ITU-T G.107.
One number instead of three technical measurements, which is why it is the figure worth watching.
How to read it
| From 4.0 | Callers are satisfied. ITU-T G.107 puts this at the "satisfied" boundary. This is where we want to be. |
| Around 3.6 | The same table's edge of "many users dissatisfied". This is where complaints start. |
| Below that | Choppy audio and words dropping out. People notice without being asked. |
| 3.5 to 4.2 | Where calls at most VoIP providers actually land. A range, not an industry average: no standards body publishes a mean. |
Why the scale never reaches 5
It cannot. Feed the E-model a flawless connection, with no packet loss, no delay and no noise, and it returns 4.41. Everything above that is arithmetic no phone call reaches.
So a dial sitting at 4.2 is not "84 percent of the way there". It is near the top of what a telephone line can do.
What the number covers
It is one average across every trunk we run, over the past 24 hours. Deliberately not per customer: the status page answers whether the platform is healthy, not how your calls went yesterday.
If you want to know how your own calls are doing, that is a different question with a different answer. Ask us and we will look at your traffic.
What moves it
Packet loss, jitter and delay, in that order of impact. On our side that is carrier and platform quality. On yours it is the local network: a saturated uplink, a switch without priority for voice, or wifi in a building that has more access points than it needs.
Comments
0 comments
Article is closed for comments.