Issue No. 11 - November (2006 vol. 17)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TPDS.2006.147
Xueyan Tang , School of Computer Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798
S.T. Chanson , Department of Computer Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong
Expiration-based consistency management is widely used to keep replicated contents up-to-date in the Internet. The effectiveness of replication can be characterized by the communication costs of client accesses and consistency management. Both costs depend on the locations of the replicas. This paper investigates the problem of placing replicas in a network where replica consistency is managed by the expiration-based scheme. Our objective is to minimize the total cost of client accesses and consistency management. By analyzing the communication cost of recursive validations for cascaded replicas, we prove that in the optimal placement scheme, the nodes not assigned replicas induce a connected subgraph that includes the origin server. Our results are generic in that they apply to any request arrival patterns. Based on the analysis, an O(D)-time algorithm is proposed to compute the optimal placement of the replicas, where D is the sum of the number of descendants over all nodes in the routing tree
computational complexity, data integrity, Internet, minimisation
Xueyan Tang and S. Chanson, "Analysis of Replica Placement under Expiration-Based Consistency Management," in IEEE Transactions on Parallel & Distributed Systems, vol. 17, no. 11, pp. 1253-1263, 2008.