In this paper, the problems of redundant traffic and redundant replicas tor efficient object replication in P2P overlay are studies. Firstly, a hierarchical and topology-aware P2P overlay is developed with κ-Medoids ...In this paper, the problems of redundant traffic and redundant replicas tor efficient object replication in P2P overlay are studies. Firstly, a hierarchical and topology-aware P2P overlay is developed with κ-Medoids partition algorithm to achieve the minimal physical distance of all super peer pairs. Secondly, a new idea of placing at most one replica in a cluster of physically adjacent nodes is introduced to achieve scattered distribution of replicas. Lastly, an efficient replicas-query algorithm based on multiple hash functions is proposed. Theoretical analysis and simulation experiment on several performance metrics are given, and it is verified that the method in this paper can efficiently disseminate replicas across the network, increase query-hit ratio, and decrease redundant messages and storage spaces required.展开更多
A novel technique called the bitmap lattice index(BLI) is proposed, which combines the advantages of a wireless broadcasting environment with a road network. Existing road networks are based on the on-demand method: a...A novel technique called the bitmap lattice index(BLI) is proposed, which combines the advantages of a wireless broadcasting environment with a road network. Existing road networks are based on the on-demand method: a server's workload increases as the query request increases when a server sends a client information. To solve this problem, we propose the BLI. The BLI denotes an object and a node as 0 and 1 in the Hilbert curve(HC) map. The BLI can identify the position of a node and an object through bit information; it can also reduce the broadcasting frequency of a server by reducing the size of the index, thereby decreasing the access latency and query processing times. Moreover, the BLI is highly effective for data filtering, as it can identify the positions of both an object and a node. In a road network, if filtering is done via the Euclidean distance, it may result in an error. To prevent this, we add another validation procedure. The experiment is conducted by applying the BLI to kNN query, and the technique is assessed by a performance evaluation experiment.展开更多
基金Supported by the National Natural Science Foundation of China （ No. 60903195 ） and the Key Technological Problems Tackling Project of Wuhan （ No. 200750499172）.
文摘In this paper, the problems of redundant traffic and redundant replicas tor efficient object replication in P2P overlay are studies. Firstly, a hierarchical and topology-aware P2P overlay is developed with κ-Medoids partition algorithm to achieve the minimal physical distance of all super peer pairs. Secondly, a new idea of placing at most one replica in a cluster of physically adjacent nodes is introduced to achieve scattered distribution of replicas. Lastly, an efficient replicas-query algorithm based on multiple hash functions is proposed. Theoretical analysis and simulation experiment on several performance metrics are given, and it is verified that the method in this paper can efficiently disseminate replicas across the network, increase query-hit ratio, and decrease redundant messages and storage spaces required.
基金supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF2013R1A1A1004593, 2013R1A1A1A05012348)
文摘A novel technique called the bitmap lattice index(BLI) is proposed, which combines the advantages of a wireless broadcasting environment with a road network. Existing road networks are based on the on-demand method: a server's workload increases as the query request increases when a server sends a client information. To solve this problem, we propose the BLI. The BLI denotes an object and a node as 0 and 1 in the Hilbert curve(HC) map. The BLI can identify the position of a node and an object through bit information; it can also reduce the broadcasting frequency of a server by reducing the size of the index, thereby decreasing the access latency and query processing times. Moreover, the BLI is highly effective for data filtering, as it can identify the positions of both an object and a node. In a road network, if filtering is done via the Euclidean distance, it may result in an error. To prevent this, we add another validation procedure. The experiment is conducted by applying the BLI to kNN query, and the technique is assessed by a performance evaluation experiment.
