Existing search mechanisms of DHT-based P2P systems allow every individual keyword to be mapped to a set of documents/nodes across the network that contains the keyword. Lookup time and Data traffic is increased. In this design proposes a decentralized semantic-aware metadata organization, called Smart Store, which exploits semantics of files metadata to judiciously aggregate correlated files into semantic-aware groups by using information retrieval tools. The key idea of Smart Store is to limit the search scope of a complex metadata query to a single or a minimal number of semantically correlated groups and avoid or alleviate brute-force search in the entire system. The decentralized design of Smart Store can improve system scalability and reduce query latency for Complex queries such as range and top-k queries. Bloom Filter to decrease space overhead and provide fast identification of stale versions by using Hashing queried items. A query in Smart-Store works as follows: initially, a user sends a query to a randomly chosen storage unit (i. e. , a leaf node of semantic R-tree). The chosen storage unit, called home unit for this request. Specifically, for a point query, the home unit servers. After obtaining query results, the home unit returns them to the user. To construct a semantic R-tree by leveraging three attributes, i. e. , file size, creation time, and last modification time.

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Smart-store Semantic R-tree Metadata Management Server Bloom Filter