On hierarchical DHT systems – An analytical approach for optimal designs

In this work, we study hierarchical DHT-based Peer-to-Peer (P2P) systems. We present an analytical model for two-tier architectures deploying a DHT at the top-level overlay and varying organizations at the lower level. Based on this model, we determine the optimal operating point of the analyzed architectures, i.e., the optimal ratio between peers at the top level and peers at the lower level. This allows us to compare the analyzed system designs and to decide which one is most suited for typical heterogeneous environments such as mobile P2P settings.