摘要：In recent years, people are recognizing that the quality in VoIP application should be evaluated according to the QoE (Quality of Experience). The main goal of this paper is to analyze the different factors on the impact of voice quality for VoIP networks. Our contributions are thus threefold: First, we establish a new VoIP simulation platform. The network simulation software is WANem, the voice communication protocol is implemented by Open Phone. This simulation system is more ‘real’ than other researcher’s system. Secondly, we analyze the factors that affect the voice quality of VoIP networks. Thirdly, we use the VoIP networks simulation platform to test the network performance impact on the quality of voice service. Through the experiment result, we can conclude that in order to get the better voice quality, we use the iLBC codec when the VoIP network is exist packet loss. And use the AMR 12.2 kb/s when the VoIP network is exist time delay
关键词：VoIP Networks;Quality of Experience (QoE); Perceptual Evaluation of Speech Quality (PESQ);Network Packet Loss
