Overnesia: an Overlay Network for Virtual Super-Peers

Unstructured P2P networks have been widely used to implement resource location systems that support complex queries semantics. Unfortunately these systems usually rely on blind search algorithms, based on flooding, which generate a significant amount of duplicate messages. An effective way to minimize the cost of query flooding in unstructured P2P networks is the use of super-peers. On the other hand, overloads or unavailability of super-peers have clearly a critical impact on the connectivity of the overlay. These issues may be addressed using the replication of super-peers, for both load balancing and fault-tolerance purposes. This paper proposes a novel algorithm to construct Overnesia, an overlay network connecting replicated super-peers. The paper also proposes techniques to perform query routing based on the unique properties of that overlay, in such a way that query processing load is distributed among replicas.