Analyzing and modifying Chord´s stabilization algorithm to handle high churn rates

Peer-to-peer (P2P) networks offer reliable and efficient services in different application scenarios. In particular, structured P2P protocols (like Chord (L. Stoica et al., 2001)) have to handle changes in the overlay topology fast and with as little signaling overhead as possible. This paper analyzes the ability of the Chord protocol to keep the network structure up to date, even in environments with high churn rates, i.e. nodes joining and leaving the network frequently. High churn rates occur, e.g., in mobile environments, where participants have to deal with the limited resources of their mobile devices, such as short battery lifetimes or high communication costs. In this paper, we analyze different design parameters and their influence on the stability of Chord-based network structures. We also present several modifications to the basic Chord stabilization scheme, resulting in a much more stable overlay topology.