TR-2007-18:Optimizing Acquaintance Selection in a PDMS
نویسندگان
چکیده
In a Peer Data Management System (PDMS), autonomous peers share semantically rich data. For queries to be translated across peers, a peer must provide a mapping to other peers in the PDMS; peers connected by such mappings are called acquaintances. To maximize query answering ability, a peer needs to optimize its choice of acquaintances. This paper introduces a novel framework for performing acquaintance selection. Our framework includes two selection schemes that effectively and efficiently estimate mapping quality. The “one-shot” scheme clusters peers and estimates the improvement in query answering based on cluster properties. The “two-hop” scheme, estimates using locally available information at multiple rounds. Our empirical study shows that both schemes effectively help acquaintance selection and scale to PDMSs with large number of peers.
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