内容分发网络中带容量和能力约束的副本放置问题研究

Study of Replica Placement Problems with Storage and Service Ability Constraints in Content Distribution Networks

副本放置问题是内容分发网络中的一项关键技术,已有的副本放置模型未考虑服务器的负载能力,本文研究考虑了基于内容分发网络服务器存储容量约束与服务能力约束的副本放置问题,建立了双约束的副本放置模型,设计了贪婪算法,把两阶段的模型求解转化成求解一系列的单服务器节点的最小费用流模型,获得了副本放置策略和用户请求重定向策略,并分析了算法的复杂性。

Replica placement is one of the key techniques in Content Distritbution Networks.Most of the past research papers ignored the sevice ablility of the edge servers.In our paper,a model with storage limit and service ability limit is proposed.We transfer the two level model into a series of Minimal Cost Flows Problems（MCFP） with single server.Greedy algorithm is used to solve the model and get user redirection schemes.The analysis of complexity of algorithm is given.