This paper describes an extensible core software element of a distributed, peer-to-peer system, which provides several facilities in order to help the implementation of collaborative, Web-based, distributed information storing and retrieval applications based on a decentralized P2P model. Moreover, after an architectural introduction of the core distributed software module, the Core Node, this paper describes a real application, named DART Node, based on it and designed and implemented within the DART (Distributed Agent-based Retrieval Tools) project, which carries out the idea of the design and implementation of a distributed, semantic and collaborative Web search engine, including mobile devices integration use cases.
