Relay node selection in large-scale VoIP overlay networks

Relay path selection is one of the critical components of VoIP overlay systems. This paper looks at the choice of relay nodes and its impact on the performance of VoIP overlay paths in interdomain environment. We model the network at the autonomous system level and simulate different scenarios of relay path selection. For the optimal relay path performance, we recommend to select relay nodes whose distances are less than or equal to three hops away from the sources. Our analysis shows that the performance of relay paths in existing methods is influenced by the density of the relay nodes. There is a trade-off between delay and hop overlap performance objectives. We propose new algorithm for selecting relay nodes. Initial results show that the proposed method can improve performance.