Quality Metrics
Ref: ITU-T Recommendation P.800 / P.862 PESQ
MOS
Mean Opinion Score
Direct Telecom Definition • Carrier Industry Standard
A standardized numerical rating from 1 (poor) to 5 (excellent) expressing the perceived audio voice quality of a telecom call.
Technical Definition & Carrier Engineering Standards
MOS measures speech intelligibility, acoustic clarity, jitter, and packet loss in VoIP transmissions. Tier-1 carrier routes aim for a minimum MOS score of 4.1 to 4.3 over G.711u/a codecs and HD voice G.722.
Standard Formula / Protocol Algorithm
R-Factor = 94.2 - Id - Ie + A, where MOS = 1 + 0.035R + R(R-60)(100-R)·7·10⁻⁶