Overlay topologies are now popular with many emerging peer-to-peer (P2P) systems, to efficiently locate and retrieve information. In contrast, the focus of this work is to use overlay topologies for transporting real-time streams on an Internet-scale. We aim to build an overlay communication system, for routing real-time data to potentially many thousands of subscribers with their own quality-of-service (QoS) requirements. In past work, we have analyzed the use of k-ary n-cube topologies for routing QoS-sensitive data. The basis for our work stems from the interconnection networks found in parallel communication architectures, such as the SGI Origin 2/3000. However, overlay networks addressed by our work are more scalable and dynamic than those found in traditional parallel computing platforms. We must address the issue of end-hosts joining and leaving the system at arbitrary times. While we have previously analyzed the optimal size and shape of an overlay, given the number of physica...