AN EFFICIENT DISTRIBUTED CONTROL LAW FOR LOAD BALANCING IN CONTENT DELIVERY NETWORKS (original) (raw)
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International Journal of Computer Applications, 2014
Content Delivery Networks (CDN) is the best for overcoming the inherited problems face by internet in modern days. The major idea at the basis of this technology is the delivery at edge points of the network, in proximity to the request areas, to advance the user's perceived performance while off-putting the overheads. Literature shows that in Content Delivery Network how this demanding problem of defining and implementing an effective law for load balancing is model. But this system has some drawback, like even if the queue length of server is low they redirect loads to another server to only balance the overall load. Due to this request processing overhead and delay increases. Algorithm model in paper can help to reduce this delay by putting one equilibrium point to request queue. In CDN, the source adjusts its rate using a modified Additive Increase and Multiplicative Decrease (AIMD) algorithm. AIMD has been demonstrated to be sufficient and essential of efficiency and fairness under certain general conditions.
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The Content Delivery Networks (CDN) paradigm is based on the idea to move third-party content closer to the users transparently. More specifically, content is replicated on servers closer to the users, and users requests are redirected to the best replica in a transparent way, so that the user perceives better content access service. In this paper we address the problem of dynamic replica placement and user requests redirection jointly. Our approach accounts for users demand variability and server constraints, and minimizes the costs paid by a CDN provider without degrading the quality of the user perceived access service. A non-linear integer programming formulation is given for the replica placement and user request redirection problems. The actual solution is obtained by mapping the non-linear integer problem into a series of mixed integer linear problems obtained by linearizing the non-linear constraints of the original problem. Preliminary numerical results show that the proposed solution is capable of effectively limiting the percentage of unsatisfied requests without over-replicating the contents over the CDN servers.
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The Content Delivery Networks (CDN) paradigm is based on the idea to transparently move third-party content closer to the users. More specifically, content is replicated on CDN servers which are located close to the final users, and user requests are redirected to the “best ” replica (e.g. the closest) in a transparent way, so that users perceive a better content access service. In this paper we address the problem of dynamic replica placement. Being dynamic, our solutions adaptively se-lect the number of replicas for each content and the repli-cas positions to account for traffic requests dynamics. The schemes we propose are designed to minimize the overall cost paid by the CDN provider (for replicas placement, re-moval, and maintenance) without degrading the quality of the users perceived access service. The contributions of the paper are twofold. First we introduce a centralized and distributed scheme for replica placement in a dynamic traffic scenario. Then, by means of a simula...
A Walk through Content Delivery Networks
Lecture Notes in Computer Science, 2004
Content Delivery Networks (CDN) aim at overcoming the inherent limitations of the Internet. The main concept at the basis of this technology is the delivery at edge points of the network, in proximity to the request areas, to improve the user's perceived performance while limiting the costs. This paper focuses on the main research areas in the field of CDN, pointing out the motivations, and analyzing the existing strategies for replica placement and management, server measurement, best fit replica selection and request redirection.
International journal of computer applications, 2015
The distributed system characterized by the distributed systems where server nodes can come up short forever with probability of nonzero, the framework execution can be evaluated by method for the administration quality, characterized as the likelihood of serving all the task lined in the distributed framework before all the failure of nodes. A Content delivery network or Content Distribution Network (CDN) is an expansive distributed systems of servers conveyed in various server farm crosswise over internet. The objective of CDN is to server with superior and accessibility. Complex component of CDN is request routing system i.e. demand for content to the suitable server focused around a particular set of parameters. Load-balancing issues emerge in numerous applications in any case; in particular, they assume an exceptional part in the operation of parallel and distributed registering systems. Load balancing manages parceling a project into littler assignments that can be executed simultaneously and mapping each of these assignments to computational sources such a processor or a machine. By creating methods that can outline tasks to processors in a manner that adjusts out the load, the aggregate handling time will be decreased with enhanced processor usage. The proposed framework will actualize the model focused around worldwide balancing that will similarly adjust the appeals in framework queue which additionally considers different delay modification plan and methods for backup with arbitrary crash of nodes or failure. This paper propose load balancing algorithm to improve stability, scalability, fault tolerance and delay adjustment.
Solving Replica Placement and Request Distribution in Content Distribution Networks
Electronic Notes in Discrete Mathematics, 2010
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 entire set of servers. In this work, exact and heuristic approaches are proposed to solve a dynamic and online problem that appears in CDN management, called the Replica Placement and Request Distribution Problem. The overall objective is to find the best servers to keep the replicas and to handle requests so that the traffic cost in the network is minimized without violating server and QoS constraints.
Optimal dynamic replica placement in Content Delivery Networks
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Content Delivery Networks (CDN) design entails the placement of server replicas to bring the content close to the users, together with an efficient and content aware request routing. In this paper we address the problem of dynamic replica placement to account for users demand variability while optimizing the costs paid by a CDN provider and the overall performance of the distributed replica servers architecture. We formulate the dynamic replica placement problem as a Semi Markov Decision Process accounting for the traffic conditions, the users level of satisfaction, as well as the costs paid to install, maintain or remove a replica from a site. The proposed model applies to general network topologies and considers realistic constraints on network and servers capacity. The optimal strategy derived by means of the decision model provides the ground for designing a centralized heuristic and is used as a benchmark for the heuristic evaluation. Simulation results show that the proposed heuristic has a behavior close to that of the optimal strategy and achieves very good performance in terms of low average distance from a user to the serving replica, low average number of replicas and high probability of being able to serve a request.