Peer-to-Peer Distribution Architectures Providing Uniform Download Rates

Abstract

Peer-to-peer (P2P) networks have proved to be a powerful and highly scalable alternative to traditional client-server architectures for content distribution. They offer the technical means to efficiently distribute data to millions of clients simultaneously with very low infrastructural cost. Previous studies of content distribution architectures have primarily focused on homogeneous systems where the bandwidth capacities of all peers are similar, or simple heterogeneous scenarios where different classes of peers with symmetric bandwidth try to minimize the average download duration. In this paper, we study the problem of content distribution under the assumption that peers have heterogeneous and asymmetric bandwidth (typical for ADSL connections), with the objective to provide uniform download rates to all peers—a desirable property for distributing streaming content. We discuss architectures that fulfill this goal and achieve optimal utilization of the aggregate uplink capacity of the peers. We develop analytical models that provide insight on their performance in various configurations, and we compare them to architectures with non-uniform rates. Our results indicate that heterogeneous and asymmetric peers can achieve uniform download rates with little additional complexity and no performance penalty.