K-overlay: A Kautz Tree Structure for Video on Demand System

In order to improve scalability and reduce maintenance overhead for Peer-to-Peer system, several architecture with constant degree and optimal diameter are proposed. However, the expected topology doesn´t effectively utilize the bandwidth capacity of peers. In this work, we propose K-overlay, an overlay scheme based on unbalanced Kautz graph with logd_n diameter and constant in-degree. We define the degree of a digraph as the maximum number of arcs arriving at or leaving from any vertex. The diameter of a graph is the number of arc traversals that is sufficient to reach any vertex from any other vertex. K-overlay structure is based on two-fold mechanism. (1) Organization of peers in concentric circles to maximize the outgoing bandwidth of peers (2) Content delivery through parent as well as neighboring peers. Through formal analysis and comprehensive simulations, we show that our proposed architecture achieves optimal diameter and good connectivity as compared to existing overlay architecture like P2Cast.