标题：Data set replica placement strategy based on fuzzy evaluation in the cloud
作者：Wu, Xiuguo; Guan, Hongjun
作者机构：[Wu, Xiuguo; Guan, Hongjun] Shandong Univ Finance & Econ, Sch Management Sci & Engn, Jinan 250014, Peoples R China.
来源：JOURNAL OF INTELLIGENT & FUZZY SYSTEMS
关键词：Cloud; replica placement; analytic hierarchy process (AHP); fuzzy; Qos
摘要：Replication technology can efficiently enhance data availability and thereby increase system reliability in cloud storage system. However, one urgent challenge is how to select the correct replica hosting sites, as different data center configurations lead to entirely different storage service quality. Additionally, users usually have individual requirements; some may care more about reliability while others are more likely to be concerned about cost. This paper investigates choosing the most suitable replica storage sites using an analytic hierarchy process (AHP) model by applying fuzzy comprehensive evaluation to candidate data centers for different kinds of users. First, a novel four-dimensional Qos (quality of service) model of cloud storage service is proposed. Then, a Qos preference-aware algorithm is introduced to deal with individual Qos sensitivity (IQS) constraints. In order to evaluate the candidate replica storage sites and select the best choices from among them, an algorithm based on fuzzy comprehensive evaluation is designed and implemented. Corresponding simulation results indicate that the strategy is suitable to serve various IQS users very well with better effectiveness and practicality.