Towards Scalable and Affordable Content Distribution Services

Content Distribution Networks (CDNs) are based on a static infrastructure, and caching and replication in CDNs are performed in a static manner. We argue that it is necessary to design future CDNs in such a way that they are scalable to reach enough customers, their costs are kept low, and they provide a Quality-of-Service that satisfies the client requirements. To reach these goals, more flexibility is needed in CDNs. Flexibility will enable CDNs to perform faster and better decisions for caching and replication, and it will reduce the amount of manual intervention that is necessary to manage and maintain the CDN. In this paper, we discuss the application of Peer-to-Peer mechanisms in CDNs that support advanced caching and replication strategies and their combination with a dynamic QoS management hierarchy to reach the needed flexibility in CDNs.