Opportunistic networking is a new communication paradigm. Content Distribution in opportunistic networks is challenging due to intermittent connectivity, short connection durations and a highly dynamic topology. Research is needed to develop new applications and protocols that can distribute content in opportunistic networks. This thesis explores and evaluates approaches to developing mobile P2...

While several mechanisms for maintaining consistency in single proxy caches exist today, not as much research has addressed ways in which such techniques may be extended to a cluster of proxy caches. If such techniques are not developed and deployed carefully, the overheads involved in maintaining cache consistency in large-scale systems such as Content Distribution Networks (CDNs) increases by...

In wireless networks, it is often assumed that all nodes cooperate to relay packets for each other. Although this is a plausible model for military or mission based networks, it is unrealistic for commercial networks and future pervasive computing environments. We address the issue of noncooperation between nodes in the context of content distribution in mobile infostation networks. All nodes h...

We have measured the performance of two commercial content distribution networks (CDNs), one operated by Akamai and one operated by Digital Island. Although there are differences in the implementation of these services, both CDNs redirect requests by using DNS. In this paper, we describe our simple measurement technique for a DNS-based CDN, our data for the two commercial services, and our inte...

Traditional content distribution networks, such as Akamai, are well-suited for static web services that routinely experience large traffic volumes. They are unsuited for active content, i.e., content generated by scripts from databases, and web sites that are unlikely to receive significant number of requests. However, a few such sites will invariably experience their “fifteen minutes of fame”,...

-This paper develops simple cost models for provisioning content distribution networks that use the simple and highly scalable bandwidth skimming protocol for streaming. New insight is obtained into (1) how cost-effective proxy servers are in multicast streaming systems, (2) the most effective streaming protocol, and (3) the optimal proxy content, as a function of the system configuration and w...

The current paradigm of Content Distribution Networks (CDN) deployment requires heavy infrastructure investment since a large number of servers have to be deployed over a wide area. To overcome this difficulty, we propose a new paradigm where future CDNs are to be deployed over a leased server infrastructure. This paradigm shift changes the object placement problem in current CDNs to a combined...

The efficient distribution of stored information has become a major concern in the Internet. Since the web workload characteristics shows that more than 60% of network traffic is caused by image documents, how to efficiently distribute image documents from servers to end clients is an important issue. Proxy cache is an efficient solution to reduce network traffic. And it has been shown that an ...

CDNs can provide scalable service that can meet aggregate user demand while improving the performance and quality of delivery. Several issues arise in the architecture of the CDNs. In this paper, we consider the routing of the user requests to the most suitable surrogates or CDNs. We model the problem as a delay-constrained routing problem and develop a near-optimal routing algorithm. We evalua...

Recently the Internet has witnessed the emergence of content distribution networks (CDNs). In this paper we study the problem of optimally replicating objects in CDN servers. In our model, each Internet Autonomous System (AS) is a node with nite storage capacity for replicating objects. The optimization problem is to replicate objects so that when clients fetch objects from the nearest CDN serv...