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To date e‐Learning material has usually been accessed and delivered through a central web server. As the number of users, the amount of information, the frequency of accesses and the volume of data increase, together with the introduction of multimedia streaming applications, a decentralized content distribution architecture is necessary. In this paper we propose the adaptation of the well‐known scalable Content Distribution Networks (CDN) schema for media streaming supported e‐Learning using a novel architecture named COMODIN SCDN (COoperative Media On‐Demand on the InterNet ‐ Streaming Content Distribution Network). COMODIN SCDN utilises surrogates as edge content delivery nodes, incorporates a redirection mechanism able to route requesting clients to the closest copy of the content, encompasses distributed content delivery and management mechanisms to improve the speed, reliability, and scalability of user access to prevent flash‐crowds. Preliminary results in testbeds have shown that COMODIN SCDN increases the efficacy of information distribution through intra and inter‐campus area netwoks. This overlay network will provide learners and educators a scalable, balanced and expeditious access to e‐Learning contents.

In this paper we present a CDN‐based system, namely the COMODIN system, which is a media on‐demand platform for synchronous cooperative work which supports an explicitly‐formed cooperative group of distributed users with the following integrated functionalities: request of an archived multimedia session, sharing of its playback, and collaboration through questioning. The server‐side architecture of the COMODIN system is organized into two integrated planes: the Base plane, which consists of a streaming CDN providing media streaming, and the Collaborative plane, which provides the collaborative playback service. At the client‐side, the system centers on a Java‐based application which interfaces the cooperative group of users.

This paper examines the design and evaluation of a TV on Demand (TVoD) system, consisting of a globally accessible storage architecture where all TV content broadcast over a period of time is made available for streaming. The proposed architecture consists of idle Internet Service Provider (ISP) servers that can be rented and released dynamically as the client load dictates. This paper examines issues of resource management and content placement within this Video Content Distribution Network (VCDN). The existing placement algorithm is computationally expensive and in some cases, infeasible to execute within any reasonable length of time. This work proposes a number of new placement heuristics each of which attempts intelligently to reduce the search space so that only the best proxies are considered for replica placement. An extensive evaluation of these placement algorithms is carried out to identify a good placement algorithm without being computationally expensive.

Streaming audio/video contents over the Internet requires large network bandwidth and timely delivery of media data. A streaming session is generally long and also needs a large I/O bandwidth at the streaming server. A streaming server, however, has limited network and I/O bandwidth. For this reason, a streaming server alone cannot scale a streaming service well. An entire audio/video media file often cannot be cached due to intellectual property right concerns of the content owners, security reasons, and also due to its large size. This makes a streaming service hard to scale using conventional proxy servers. Media file compression using variable‐bit‐rate (VBR) encoding is necessary to get constant quality video playback although it produces traffic bursts. Traffic bursts either waste network bandwidth or cause hiccups in the playback. Large network latency and jitter also cause long start‐up delay and unwanted pauses in the playback, respectively. In this paper, we propose a proxy based constant‐bit‐rate (CBR)‐transmission scheme for VBR‐encoded videos and a scalable streaming scheme that uses a CBRtransmission scheme to stream stored videos over the Internet. Our CBR‐streaming scheme allows a server to transmit a VBRencoded video at a constant bit rate, close to its mean encoding bit rate, and deals with the network latency and jitter issues efficiently in order to provide quick and hiccup free playback without caching an entire media file. Our scalable streaming scheme also allows many clients to share a server stream. We use prefix buffers at the proxy to cache the prefixes of popular videos, to minimize the start‐up delay and to enable near mean bit rate streaming from the server as well as from the proxy. We use smoothing buffers at the proxy not only to eliminate jitter and traffic burst effects but also to enable many clients to share the same server stream. We present simulation results to demonstrate the effectiveness of our streaming scheme.

The purpose of this paper is to articulate whether consumers’ use of music via streaming service benefits niche products and diversified consumption of music. It examines does winner take all or is long tail achieved in the digital music market.

To investigate the degree of concentration in the digital music sales, this study measures multiple concentration metrics using the top 100 songs for 245 weeks listed on the Korean music ranking chart.

Conflicting results are found between the analyses based on short-run and long-run data. When sales distributions are compared weekly or monthly, the results show that streaming services have a less concentrated sales distribution than download services. However, the result becomes the opposite in the long-run analysis (i.e. one year).

This study proposes that the non-technological drivers such as the beneficial addiction of music consumption can be a crucial driver affecting the usage concentration in music industry, coupled with the royalty policy of access-based services.

The selection, integration and management of digital collections will be affected by current changes in the way audio visual content is delivered on the Internet. Describes a technology shift in audio visual content delivery, which pushes content to the “edge” of the Internet, thereby reducing bandwidth loads and improving user experience. Strategies that will allow information professionals to exploit this change are relevant to librarians and archivists who might otherwise opt for a centralized model of content distribution.

Information-centric networking (ICN) is an innovative paradigm for the future internet architecture. This paper aims to provide a view on how academic video lectures can exploit the ICN paradigm. It discusses the design of academic video lectures over named data networking (NDN) (an ICN architecture) and speculates their future development. To the best of author’s knowledge, a similar study has not been presented.

The paper is a visionary essay that introduces the background, elaborates the basic concepts and presents the author’s views and insights into academic video lectures that exploit the latest development of NDN approach and its applications.

The ICN paradigm is closely related to the levels of automation and large-scale uptake of multimedia applications that provide video lectures. Academic video lectures over NDN have: improved efficiency, better scalability with respect to information/bandwidth demand and better robustness in challenging communication scenarios. A framework of academic video lectures over NDN must take into account various key issues such as naming (name resolution), optimized routing, resource control, congestion control, security and privacy. The size of the network in which academic video lectures are distributed, the content location dynamics and the popularity of the stored video lectures will determine which routing scheme must be selected. If semantic information is included into academic video lectures, the network dynamically may assist video (streaming) lecture service by permitting the network to locate the proper version of the requested video lecture that can be better delivered to e-learners and/or select the appropriate network paths.

The paper helps researchers already working on video lectures in finding a direction for designing and deploying platforms that will provide content-centric academic video lectures.

The paper pioneers the investigation of academic video lecture distribution in ICN and presents an in-depth view to its potentials and research trends.

Video distribution over the internet leads to heated net‐neutrality related debates between network operators and over‐the‐top application providers. The purpose of this paper is to analyze this debate from a new perspective that takes into account all of the assets that companies try to exploit in the so‐called battle for eyeballs in video distribution.

The systematic value chain analysis is used to determine the points along the value chain where net neutrality interacts with video distribution. The inputs to the analysis are the existing and proposed policy measures for net neutrality in Europe and in the USA, and a number of net neutrality incidents that have led to discussions earlier.

The paper finds that the current and proposed policy measures aimed at net neutrality each contribute to a certain extent to their intended effects. However, the analysis also shows that they are likely to lead to new debates in other parts of the value chain, as players try to compensate the loss of influence or revenue streams by rearranging the ways in which they exploit their assets.

Further and new debates are expected in the areas of peering and interconnection, distribution of resources between over‐the‐top and managed services and the role of devices with tightly linked search engines, recommendation systems and app stores.

The new perspectives offered by our value‐chain based analysis are valuable for policy makers who aim to promote net neutrality and simultaneously stimulate competition and innovation throughout the value chain.

This paper aims to argue on the efficiency of Quality of Service (QoS)-based adaptive streaming with regards to perceived quality Quality of Experience (QoE). Although QoS parameters are extensively used even by high-end adaptive streaming algorithms, achieved QoE fails to justify their use in real-time streaming videos with high motion. While subjective measurements of video quality are difficult to be applied at runtime, objective QoE assessment can be easier to automate. For end-to-end QoS optimization of live streaming of high-motion video, objective QoE is a more applicable approach. This paper contributes to the understanding of how specific QoS parameters affect objective QoE measurements on real-time high-motion video streaming.

The paper approached the question through real-life and extensive experimentation using the Skype adaptive mechanisms. Two Skype terminals were connected through a QoS impairment box. A reference video was used as input to one Skype terminal and streamed on one direction. The impairment box was stressing the stream with different conditions. Received video was stored and compared against the reference video.

After the experimental analysis, the paper concludes that adaptive mechanisms based on QoS-related heuristics fail to follow unexpected changes to stream requirements. High-motion videos are an example of this variability, which makes the perceived quality sensitive to jitter more than to packet loss. More specifically, Skype seems to use if-else heuristics to decide its behavior to QoS changes. The weaknesses to high-motion videos seem to lie on this rigidity.

Due to the testbed developed, the results may be different if experiments are run over networks with simultaneous streams and a variety of other traffic patterns. Finally, other streaming clients and algorithms would contribute to a more reliable generalization.

The paper motivates video streaming engineers to emphasize their efforts toward QoE and end-to-end optimization.

The paper identifies the need of a generic adaptive streaming algorithm able to accommodate a big range of video characteristics. The effect of QoS variability to high-motion video streaming helps in modeling and design.

The purpose of this paper is to explore the impact of the internet as an emerging video distribution platform and to analyze the corresponding emerging economic and legal issues.

The paper describes the historical evolution of the business model for the television business and, using a layered model of communications, identifies issues that accompany the growth of the internet as both a complement and a competitor to existing distribution platforms.

As video is increasingly distributed using the internet, a new business model is developing that possesses characteristics such as, unbundled content, irrelevance of geographic exclusivity, irrelevance of structured time or structured release, and new business combinations, alliances, and ventures.

Public policy makers throughout the world are faced with the need to update, replace, and/or revise existing regulations that govern the relationships between and among traditional video distribution platforms, such as over‐the‐air and cable/satellite providers, as the internet emerges as a viable video distribution platform.

The paper provides a summary of key economic (such as the network‐affiliate relationship) and regulatory issues (such as leveraging economic power in the physical and logical layers into the applications and content layers and the extension of content regulation) that are developing as the internet emerges as a video distribution platform.