Optimal Unicast Path Selection Algorithm in the Overlay Multicast

In this paper, we present a two-layer overlay multicast framework for building an application-layer multicast(ALM) system model. The framework employs an optimal unicast path selection (OUPS) algorithm, which can select QoS-satisfied multicast tree path for stream applications. This algorithm is proposed to compute the QoS weight values of paths in overlay network, and to select optimal unicast path for ALM. This approach balances delay and bandwidth available requests using path weight adjuster. Compared to random unicast path selection algorithm, our approach achieves better minimized delay and maximized bandwidth available. Large-scale simulations demonstrate the efficiency and performance of the multicast framework The results can be used for a variety of live real-time distribution stream applications, such as IPTV, VOD and so on.