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A Scalable P2P Platform for the Knowledge Grid
December 2005 (vol. 17 no. 12)
pp. 1721-1736
The Knowledge Grid needs to operate with a scalable platform to provide large-scale intelligent services. A key function of such a platform is to efficiently support various complex queries in a dynamic large-scale network environment. This paper proposes a platform to support index-based path queries by incorporating a semantic overlay with an underlying structured P2P network that provides object location and management services. Various distributed indexing structures can be dynamically formed by publishing semantic objects as indexing nodes. Queries are forwarded along the chains of semantic object pointers to search for objects. We investigate the deployment of a scalable distributed trie index for broadcast queries on key strings, propose a decentralized load balancing method for solving the problem of uneven load distribution incurred by heterogeneity of loads and node capacities and by the distributed trie index, and give an approach for improving the availability of the semantic overlay and its trie index. Experiments demonstrate the scalability of the proposed platform.

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Index Terms:
Index Terms- Peer-to-peer, semantic overlay, knowledge grid, path query, distributed trie index, load balancing, replication.
Hai Zhuge, Xiaoping Sun, Jie Liu, Erlin Yao, Xue Chen, "A Scalable P2P Platform for the Knowledge Grid," IEEE Transactions on Knowledge and Data Engineering, vol. 17, no. 12, pp. 1721-1736, Dec. 2005, doi:10.1109/TKDE.2005.190
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