A Content Distribution Network (CDN) is an overlay network where servers replicate contents and distribute client’s requests with the aim at reducing delay, server load and network congestion, hence improving the quality of service (QoS) perceived by end clients. Because of server constraints and costs involved in the replication process, it is not reasonable to replicate the contents over the ...

In this paper, we discuss and compare several policies to place replicas in tree networks subject to server capacity. The client requests are known beforehand, while the number and location of the servers are to be determined. The standard approach in the literature is to enforce that all requests of a client be served by a single server in the tree (Single). One major contribution of this pape...

The online video service need the support of CDN(Content Delivery Networks). Compared with traditional CDNs, it can save a lot of cost by using cloud-based storage nodes to deliver the video content. To guarantee end users’ QoS, CDN should pre-deploy the content files of online video service to the edge nodes which are close to the users. Existed researches have shown that the cost of building ...

Data replication is typically used to improve access performance and data availability in Data Grid systems. To date, research on data replication in Grid systems has focused on infrastructures for replication and mechanisms for creating/deleting replicas. The important problem of choosing suitable locations to place replicas in Data Grids has not been well studied. In this paper, we address th...

A new model describing dependencies among system components as a directed graph is presented and used to solve a novel replica placement problem in data centers. A criterion for optimizing replica placements is formalized and explained. In this work, the optimization goal is to choose placements in which correlated failure events disable as few replicas as possible. A fast optimization algorith...

In complex systems, such as data centers, component failure is ubiquitous. Studies have shown that many complex systems do not effectively mitigate the impact of correlated failures. A model for handling correlated failure based upon hierarchical dependencies between multiple points of failure is presented. The dependency model is generic in the sense that it makes no assumptions concerning the...

In this paper, a mathematical model for data object replication in ad hoc networks is formulated. The derived model is general, flexible and adaptable to cater for various applications in ad hoc networks. We propose a game theoretical technique in which players (mobile hosts) continuously compete in a non-cooperative environment to improve data accessibility by replicating data objects. The tec...

Caching and replication have emerged as the two primary techniques for reducing the delay experienced by end-users when downloading web pages. Even though these techniques may benefit from each other, previous research work tends to focus on either one of them separately. In particular, caching has been studied mostly in the context of proxy server systems, while replication is the technology b...

Content Distribution Networks have been attracted a great deal of attraction in recent years. Replica placement problems (RPPs) as one of the key technologies in the Content Distribution Networks have been widely studied. In this paper, we propose an optimization model with server storage capacity constraints for the RPPs. Furthermore, part of the objective function is represented as a Multiple...

Content distribution networks (CDN) have been increasingly used as the scalable solution to deliver high-quality multimedia content. However, despite the promising concept, current self-organizing content distribution networks (using realtime replica placement) lack placement and retrieval algorithms that are both intelligent and scalable. In this paper we present an architecture and relating a...