HyPeer: Structured overlay with flexible-choice routing

The various designs of peer-to-peer distributed hash tables (DHTs) differ mostly in their performance and the properties they provide. They usually rely on a single greedy routing strategy aiming at achieving short communication paths. In this paper, we propose a new peer-to-peer DHT overlay design, HyPeer, that uses the “flexible-choice routing” principle to support multiple routing strategies, each driven by a different objective: fault tolerance, load balance, low latency. Our overlay is loosely based on a hypercube structure providing redundant paths that can be selectively followed at runtime according to the desired goal. HyPeer approximates a hypercube by extending a ring-based DHT overlay and controlling the placement of nodes when they join the network. Experimental evaluation confirms that HyPeer succeeds in improving the routing performance according to our three design objectives, while only slightly increasing the average path length.