The Common Problems on the Peer-to-Peer Multicast Overlay Networks

Peer-to-peer overlay, a more promising topology construction, promotes the development of Application Layer Multicast. There have been many studies on the overlay construction and improve the multicast performance. Most of these studies focused on the building period of overlay network or multicast tree. After the overlay construction is established, it will remains stable unless churn of overlay (peers leaving and joining). It is not flexible in the heterogeneous and variable Internet environment. In this paper we analyzed three overlay constructions of the P2P-based ALM from single-tree, multi-tree to mesh, some key problems affecting the multicast performance are considered including the tradeoff between depth and out-degree, the available ratio of leaf nodes, and the influence on the churn of overlay.