DRing: A Layered Scheme for Range Queries over DHTs

Traditional DHT structures provide very poor support for range queries, since uniform hashing destroys data locality. Several schemes have been proposed to overcome this issue, but they fail to combine load balancing, low message overhead, and low latency in search operations. In this article we present DRing, an efficient layered solution that directly supports range queries over a ring-like DHT structure. We improve load balancing by using only the nodes that store data, and by updating neighbour information through an optimistic approach. DRing produces low overhead and low latency in environments where queries significantly outnumber data insertion operations. We analyze DRing through simulation and show that our solution does not rely on data distribution.