Assessment of VoIP quality over access networks

This paper assesses VoIP quality over access networks in Pakistan using a delay jitter measurement methodology for evaluating the perceptual quality of voice calls using the ITU-T G.107 speech quality E-model. Passive measurements for voice calls in the presence of background Internet data traffic for G.723.1 and G.729a codecs are carried out using a non-intrusive parametric model. The R-factor and resultant Mean Opinion Scores (MOS) were calculated at different link loads and congestion hot spots were identified. The study highlights the inadequacy of access networks for handling VoIP traffic at current in Pakistan and suggests alleviating congestion by increasing capacity in access networks.