A complete content production and delivery system in a controlled multimedia network

Cloud providers give storage access and efficient content placement and delivery services to content providers by optimizing cloud-based content delivery. The cost-efficient model should not only consider the content delivery cost but also the storage cost associated with the cloud network. In this article, a novel cloud-based content delivery model is proposed that uses shared storage models for cost optimization in content delivery. Shared storages are placed in different areas of the content delivery network and an efficient replica placement strategy is employed using optimization techniques. Different content delivery schemes are used in proposed model for different situations and overall content delivery cost is optimized. Experimental results show better performance and lesser cost in terms of storage, traffic and latency and also satisfy Quality-of-Service (QoS) and Quality-of-Experience (QoE) in content delivery using PSO when compared to ACO and GA.

Over the last years, the content delivery network (CDN) market has been witnessing globally an increase in the development of cloud-based CDNs, as they constitute a viable and cost-effective alternative to traditional commercial CDNs. Towards that direction, Social-Aware Virtual Network Embedding (SAViNE) for wireless content delivery within the OpenLab project aims at establishing, assessing, and prototyping a novel framework for deploying a CDN over the wireless cloud. Specifically, the goal of SAViNE is to provide experimental validation of the efficiency of social network analysis (SNA) - inspired surrogate server placement strategies, devised for fostering content delivery. The proposed framework has been integrated with the OpenLab experimental facilities, providing a run-time environment for CDN deployment, operation, and performance evaluation over the wireless environment. The framework’s feasibility and scalability is experimentally validated. The study is complemented with repeatability evaluation of experimental measurements, related to the resulting CDN’s operational efficiency.

Recognizing content delivery and caching as an increasingly important topic in future wireless networks, this workshop aims at bringing together experts from different communities, including networking, communications, computer science, operation research, and machine learning, to shed light on the latest developments in the field. The 1st edition of the workshop achieved this goal, as the 8 accepted papers and one keynote speech covered many aspects of efficient caching and content delivery, ranging from coding techniques for caching assisted content delivery to cache management policies and methods.

Broadband network technologies have improved the bandwidth of the edge of the Internet but its core is still a bottleneck for large file transfers. Content Delivery Networks (CDNs), built at the edge of the Internet, are able to reduce the workload of network backbones but their scalability and network reach is often limited, especially in case of QoS-bound delivery services. By using the emerging CDN internetworking, a CDN can dynamically exploit resources of other cooperating CDNs to face peak loads and temporary malfunctions without violating QoS levels negotiated with content providers. This paper proposes an architectural schema and an algorithm to minimize transfer time of large files taking into account the SLA constraints agreed between the CDN in charge of content delivery and the content provider, while respecting the maximum budget that the CDN can pay to peer CDNs to ensure its revenue. The experimental analysis confirms the benefits of applying the proposed algorithm in CDN internetworking to enforce SLA guarantees of CDN services.

Content delivery over Internet is optimized for low use perceived latency by designing specialized Content Distribution Network (CDN). Content servers are connected through a content switch the distributes client requests among them to achieve load balancing across the servers. The content switch is located one-hop away from the servers. Server load balancing is one factor in achieveing low user perceived latency and improving operational efficiency. Traffic engineering is another factor that is generally and integrated with serverload balancing for CDN optimization. In this thesis we propose a request routing algorithm for a CDN that was designed to integrate server selection and traffic engineering functions in the request routing system. The CDN employs MPLS in the network for traffic engineering. The proposed algorithm optimizes content delivery for user perceived latency by achieving server load balancing and network traffic loan manaement among alternative paths. It also improves operational efficiency of the CDN by eliminating bottleneck paths and increasing utilization of underutilized servers and paths.

The Internet has become along the years a pervasive network interconnecting billions of users and is now playing the role of collector for a multitude of tasks, ranging from professional activities to personal interactions. From a technical standpoint, novel architectures, e.g., cloud-based services and content delivery networks, innovative devices, e.g., smartphones and connected wearables, and security threats, e.g., DDoS attacks, are posing new challenges in understanding network dynamics. In such complex scenario, network measurements play a central role to guide traffic management, improve network design, and evaluate application requirements. In addition, increasing importance is devoted to the quality of experience provided to final users, which requires thorough investigations on both the transport network and the design of Internet services. In this thesis, we stress the importance of users' centrality by focusing on the traffic they exchange with the network. To do so, we design methodologies complementing passive and active measurements, as well as post-processing techniques belonging to the machine learning and statistics domains. Traffic exchanged by Internet users can be classified in three macro-groups: (i) Outbound, produced by users' devices and pushed to the network; (ii) unsolicited, part of malicious attacks threatening users' security; and (iii) inbound, directed to users' devices and retrieved from remote servers. For each of the above categories, we address specific research topics consisting in the benchmarking of personal cloud storage services, the automatic identification of Internet threats, and the assessment of quality of experience in the Web domain, respectively. Results comprise several contributions in the scope of each research topic. In short, they shed light on (i) the interplay among design choices of cloud storage services, which severely impact the performance provided to end users; (ii) the feasibility of designing a general purpose classifier to detect malicious attacks, without chasing threat specificities; and (iii) the relevance of appropriate means to evaluate the perceived quality of Web pages delivery, strengthening the need of users' feedbacks for a factual assessment.

Today’s content delivery networks (CDNs) use large sets of globally distributed servers, advanced routing techniques, and dynamic server selection to provide users with low delay, reliable access to Web, and streaming content. These strategies allow CDNs to extend their reach and performance into large numbers of networks around the globe. However, nearly 20% of Internet users reside in China, where local regulations and network policies make it challenging for global CDNs to serve foreign content from servers in China and limit the effectiveness of their traditional strategies for low-latency content delivery. Recently, a number of China-specific CDNs have partnered with global CDNs to provide service in the country. However, little is known about how CDNs in China are implemented, nor their impact on performance. In this paper, we are the first to investigate the impact of China’s unique policy and networking environment on CDN implementations and deployments. We find that deployments inside China exhibit different client-mapping behavior than global ones, namely, through static server selection for clients given a customer site, and through region-specific clients partitioning and mapping rather than using live network information. We also show that ignoring these properties can significantly impact server selection quality. Our results can be useful for optimization of CDNs in China.

Real-time content delivery (RTCD) systems have become a prominent aspect of telecommunications as evidence by popularity of news-casting, real-time event subscription / publication and live media streaming. Unlike conventional content delivery systems, RTCDs need to deliver processed information to users in real time. This may require the network to handle some of the processing closer to the users to efficiently use the bandwidth consumed by the applications. The combination of Network Function Virtualization (NFV) and service chaining is a promising solution to address this challenge. Our work applies a service chaining algorithm to place NFV modules of an RTCD application in a Software Defined Infrastructure (SDI), where virtualized Customer Premise Edges (vCPEs), possessing scarce resources, are employed. We suggest containers to efficiently pack VNFs into vCPEs. Our objective is to maximize the total number of chains that can be serviced in the RTCD application. To optimally chain the NFV modules, a heuristic algorithm is proposed and evaluated. Using simulations, we show that our algorithm with the help of vCPEs can support higher number of users while providing high-level service quality.

With the trend of cloud computing, more and more web applications move their content to external storage services to reduce the cost of hardware and maintenance. In this paper, a novel architecture called CloudEdge for Content Delivery Network (CDN) with the storage service in cloud computing is introduced. This architecture could not only keep the loosely coupled integration between storage service and web applications but also provide better content manipulation features such as edge network content delivery, caching, secured access control, the variations of content objects generated on demand, and post-process on content objects.

Contents Delivery Networks (CDNs) have been introduced to deliver efficiently very large content to user with low cost. For this, various content delivery schemes such as the uncooperative pull-based scheme, the cooperative push-based scheme, and the cooperative pull-based scheme, have been studied in CDNs. However, these schemes hold the problems such as temporary service interruption, the increases of the average delivery time of content and the bottlenecks to the Internet backbone. In this paper, we propose the content delivery scheme called the cooperative hybrid-based scheme that enables efficient operation of limited resources. Through simulation, we confirmed the service without temporary interruption, the average delivery time of content improved by up to 8%, and the bottlenecks to the Internet backbone between ISPs reduced by up to 66%.

Social Welfare Implications of Different Cache Deployment Scenarios

Increasing over-the-top video consumption makes the delivery of content unsustainable in the current Internet. The Internet Service Providers (ISP) have a hard time competing on value-added services with content providers and content delivery networks (CDN). We propose a new model of collaboration between content delivery actors where CDNs can deploy their software in Internet Service Providers' infrastruc-ures as NFV modules. As the ISP network state has to be kept private, a high-level SLA is used to negotiate both computing resources and connectivity, leaving it up to the ISP to optimize server placement and routes. The contribution of this paper is to formalize this problem as a Service Function Chaining Embedding problem, and to propose an algorithm to optimize the Service Function Chain to improve embedding probability and decrease consumed bandwidth in the process.

With the rapid growth of internet traffic, the traditional host-to-host TCP/IP architecture is subject to many service limitations faced with content-oriented applications. Various novel network architectures have been proposed to solve these limitations, among which Information-Centric Networking (ICN) is one of the most prominent. ICN features the decoupling of content (service) from the physical devices storing (providing) it through location-independent naming, and offers inherent enhancement to network performance, such as multicast and in-network caching. ICN in-network caching has been extensively studied, and we believe that it may also be the main incentive for ISPs to deploy ICN. A CDN (content delivery network) is a typical content-oriented network paradigm that aims to provide the fast delivery of content. In this paper, we leverage the advantages of the in-network caching of ICN to enhance the content delivery efficiency of CDN by integrating ICN as a service. First, we present our design of a content delivery network enhanced with ICN, called IECDN. Additionally, we formulate a mathematical model to optimize the performance of our proposed design and conduct a series of evaluations. The results indicate that our proposed design provides significant performance gains while reducing bandwidth consumption and shows better resilience to traffic surge.

Recently, large-volume contents distributed by a content delivery network (CDN) on the Internet increase the load of content delivery servers and networks, which may degrade the quality of service. To overcome this problem, some mirror servers providing the same content are located on a network, and a request is navigated to one of the mirror servers. It is important to locate the mirror servers on the appropriate place in a network, as it affects the performance of the CDN. In this paper, we address the server location problem, which determines the location of the mirror servers satisfying the following two constraints: the number of the paths to the servers in a link is small, and the number of the nodes whose nearest mirror server is the same is small. The former constraint corresponds to the alleviation of the network load, and the latter constraint corresponds to the alleviation of the server load. First, we prove that this new server location problem is NP-complete. Next, we present a heuristic algorithm and evaluate it by applying to some actual network topologies. The results show that the algorithm can determine a good server location.

Modern websites use Content Delivery Networks (CDNs) to speed up the delivery of static content. However, we show that DNS-based selection of CDN servers can be refined to fully deliver on the speedup of CDNs. We propose DNS-Proxy (dp), a client-side process that shares load-balancing functionality with CDNs by choosing from among resolved CDN servers based on last mile network performance. Our measurement study of CDN infrastructure deployed by five major CDN providers shows that dp reduces webpage load time by 29% on average. If dp has already resolved the domain, the reduction in webpage load time is as much as 40%. Finally, dp reduces the load time of individual static Web objects by as much as 43%. We argue that dp enables a more effective use of existing content delivery infrastructure and represents a complementary strategy to a continual increase of geographic content availability.