Optimizing Voice-over-IP Speech Quality Using Path Diversity

In last few years, voice over Internet protocol (VoIP) has been gaining popularity as an alternative to traditional telephone by transmitting voice signals as packets over the Internet and private IP-based networks. However, voice packets experience loss, delay, and delay variation, which requires buffering, playout scheduling and loss concealment at the receiver. In this paper, we give an overview of a VoIP application and show how playout scheduling and loss concealment are jointly used to optimize perceived speech quality. We use this optimization criterion to design a histogram-based playout scheduling algorithm. Then, we identify the limitations of the VoIP application for this scheme and propose improvement using path diversity approach that can be implemented via a service overlay network (SON). We present simulations results that show significant improvement of VoIP quality by using this approach