Fast but economical: A simulative comparison of structured peer-to-peer systems

In the past many proposals for structured peer-to-peer protocols have been published. They differ in properties like overlay topology and routing table maintenance. Furthermore, each protocol exhibits various parameters e.g. to adjust the size of the routing table or stabilization intervals, making it difficult to choose an optimal protocol and parameter set for a given scenario (e.g. churn rate, number of nodes). For this purpose, we developed the overlay simulation framework OverSim and implemented six well known structured overlay protocols. In this paper we first compare these protocols among each other. Furthermore, we study several recursive and iterative routing variants and show the effect of routing table redundancy and lookup parallelism on routing latency and bandwidth costs. For each overlay protocol we identify an optimal parameter set for a typical peer-to-peer scenario. Finally, we show how overlay protocols adapt to variations in churn rate and network size. Our results show considerable advantages of the protocols Kademlia and Bamboo, while De Bruijn based protocols reveal a lack of stability under churn.