Organizing XML Documents on a Peer-to-Peer Network by Collaborative Clustering

In this chapter we address the problem of clustering XML documents in a collaborative distributed environment. We developed a clustering framework for XML sources distributed on a P2P network. XML documents are modeled based on a transactional representation which uses both XML structure and content information. The clustering method employs a centroid-based partitional scheme suitably adapted to work on a P2P network. Each peer is enabled to compute a clustering solution over its local repository and to exchange the resulting cluster representatives with the other peers. The exchanged cluster representatives are hence used to compute the global clustering solution in a collaborative way. Effectiveness and efficiency of the framework were evaluated on real XML document collections varying the number of peers. Experimental results have shown significant improvements of our collaborative distributed algorithm with respect to the centralized clustering setting in terms of execution time, achieving clustering solutions that still remain accurate with a moderately low number of nodes in the network.