CONTENTS

 1     Introduction
 2     Loss (a-b) to avoid instability during set-up, clear-down and changes in a connection
 3     Unweighted loss (a-b) on established connections
 4     Echo loss (a-b) on established connections
Annex A – Measurement of stability loss (a-b) and echo loss (a-b)
Annex B – Explanation of terms associated with the path a-t-b
        B.1     Return loss
        B.2     Balance return loss
        B.3     Transmission loss of the path a-t-b
        B.4     Stability and echo losses
        B.5     Overall loudness rating of the echo path (talker echo loudness rating, TELR)
        B.6     Summary of useful terms
References