The main properties of Distributed Hash Tables are scalability, robustness, fault-tolerance. In the XML context, structural paths may be indexed in a P2P architecture using Distributed Hash Tables. However, evaluating structural twig-queries (i.e., queries with multiple branching paths) on a DHT is not very efficient as multiple DHT lookups are required. Moreover, the DHT lookups are limited to exact match and thus not helpful for range queries. In this paper, we propose an indexing mechanism suitable for prefix based path indexing, structural twig-query and range query execution, inspired from classical DHT structures. Our design and implementation are based on a specific method of mapping paths into a particular DHT indexing space. We validate our architecture by several experiments that test the main functionalities of the system.
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