P2P streaming and in particular P2P support for IP-TV are becoming not only hot research topics, but also available systems and services like [1–5].Fundamental to support live streaming is the guarantee of a low distribu- tion delay of the information to all peers. This is strictly related to the overlay characteristics and the scheduling that distribute chunks to peers.The community has been divided on whether structured systems, i.e., an overlay with known and controlled topological properties like a tree or a hy- percube, or unstructured systems based on general meshes are better for this scope. The advantage of structured systems lies in the possibility of finding de- terministic scheduling that achieve optimal performance, but they are normally fragile in face of churn (coming and leaving of nodes), require signaling for the overlay maintenance, and can be complex to manage. Unstructured systems, instead, are robust and easy to manage. Overlay maintenance only requires con- nectivity: each node autonomously search and contact its own neighbors. Their disadvantage has been so far the impossibility of finding a distributed scheduling algorithm that is optimal and robust under normal operating conditions.
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