Robustness of a P2P community management system based on two-level hierarchical DHT overlays

The popularity of community-centric applications has rapidly grown during the recent years. In this paper, we evaluate the robustness of a P2P community management system, where communities are established as autonomous DHT overlays that are advertised in a global DHT overlay. The evaluation is based on the experimental measurements conducted using a DHT-based protocol with two DHT algorithms called Kademlia and Chord. The robustness of the P2P community management system was evaluated with different levels of churn and node activity, in terms of nodes´ look-up success ratio, network traffic load and average hop count. The P2P community management system was also compared against a flat DHT structure where all the community related activities are performed in a single DHT overlay. The evaluation results suggest that the P2P community management system performs very well in an environment with high level of churn, the performance improvement being especially significant with Chord.