DSL loop qualification by using noise margin

This paper through the results of experimental research collected in real system under commercial exploitation investigates the significance of recommended ratio for one of physical layer parameter — SNR margin for the needs of loop qualification for IPTV over xDSL. At the beginning of this paper, a short definition and recommended value for SNR margin is given. In the rest of the paper the measured values of this parameter for 500 xDSL lines and made discussions the practical importance of this parameter for loop qualification are also given.