National University Of Ireland
ITU-T recommendation G.107 introduced the Emodel, a repeatable way to assess if a network is prepared to carry a VoIP call or not. Various studies show that the Emodel is complex with many factors to be used in monitoring purposes. Consequently, simplified versions of the E-model have been proposed to simplify the calculations and focus on the most important factors required for monitoring the call quality. In this paper, the authors propose simple correction to a simplified E-model; they show how to calculate the correction coefficients for 4 common codecs (G.711, G.723.1, G.726 and G.729A) and then they show that its predictions better match PESQ scores by implementing it in a monitoring application.