scope:

This document is intended for use as the North American standard for mapping measurements made with In-Service, Non-intrusive Measurement Devices (INMDs) to the parameters used in customer opinion models for voice services. This standard includes mathematical algorithms which perform this mapping and allow customer opinion ratings to be determined from INMD measurements. This will allow INMD measurements to be used to evaluate the performance of telecommunications connections and services and to detect speech level, noise, and echo anomalies on telecommunications connections. Although other impairments affect voice transmission, only loss, noise, and echo are studied here. The algorithms specified here are applicable to metallic loop systems terminated in modern electronic telephones, as well as other equivalent network connections and terminal equipment.

It is the intention of this standard to use and align with the relevant ITU-T Recommendation.

This alignment effort consists of adopting ITU-T Recommendation P.562.