FlexStream: SDN-Based Framework for Programmable and Flexible Adaptive Video Streaming

With the tremendous increase in video traffic fueled by smartphones, tablets, 4G LTE networks, and other mobile devices and technologies, providing satisfactory services to end users in terms of playback quality and a fair share of network resources become challenging. As a result, an HTTP video streaming protocol was invented and widely adopted by most video providers today with the goal of maximizing the user’s quality of experience. However, despite the intensive efforts of major video providers such as YouTube and Netflix to improve their players, several studies as well as our measurements indicate that the players still suffer from several performance issues including instability and sub-optimality in the video bitrate, stalls in the playback, unfairness in sharing the available bandwidth, and inefficiency with regard to network utilization, considerably degrading the user’s QoE. These issues are frequently experienced when several players start competing over a common bottleneck. Interestingly, the root cause of these issues is the intermittent traffic pattern of the HTTP adaptive protocol that causes the players to over-estimate the available bandwidth and stream unsustainable video bitrates. In addition, the wireless network standards today do not allow the network to have a fine-grain control over individual devices which is necessary for providing resource usage coordination and global policy enforcement. We show that enabling such a network-side control would drive each device to fairly and efficiently utilize the network resources based on its current context, which would result in maximizing the overall viewing experience in the network and optimizing the bandwidth utilization. In this dissertation, we propose FlexStream, a flexible and programmable Software-Defined Network (SDN) based framework that solves all the adaptive streaming problems mentioned above. We develop FlexStream on top of the SDN-based framework that extends SDN functionality to mobile end devices, allowing for a fine-grained control and management of bandwidth based on real time context-awareness and specified policy. We demonstrate that FlexStream can be used to manage video delivery for a set of end devices over WiFi and cellular links and can effectively alleviate common problems such as player instability, playback stalls, large startup delay, and inappropriate bandwidth allocation. FlexStream offloads several tasks such as monitoring and policy enforcement to end-devices, while a network element (i.e., Global Controller), which has a global view of a network condition, is primarily employed to manage the resource allocation. This also alleviates the need for intrusive, large and costly traffic management solutions within the network, or modifications to servers that are not feasible in practice. We define an optimization method within the global controller for resource allocation to maximize video QoE considering context information, such as screen size and user priority. All features of FlexStream are implemented and validated on real mobile devices over real Wi-Fi and cellular networks. To the best of our knowledge, FlexStream is the first implementation of SDN-based control in a live cellular network that does not require any internal network support for SDN functionality

An Advanced A-V- Player to Support Scalable Personalised Interaction with Multi-Stream Video Content

PhDCurrent Audio-Video (A-V) players are limited to pausing, resuming, selecting and viewing a single video stream of a live broadcast event that is orchestrated by a professional director. The main objective of this research is to investigate how to create a new custom-built interactive A V player that enables viewers to personalise their own orchestrated views of live events from multiple simultaneous camera streams, via interacting with tracked moving objects, being able to zoom in and out of targeted objects, and being able to switch views based upon detected incidents in specific camera views. This involves research and development of a personalisation framework to create and maintain user profiles that are acquired implicitly and explicitly and modelling how this framework supports an evaluation of the effectiveness and usability of personalisation. Personalisation is considered from both an application oriented and a quality supervision oriented perspective within the proposed framework. Personalisation models can be individually or collaboratively linked with specific personalisation usage scenarios. The quality of different personalised interaction in terms of explicit evaluative metrics such as scalability and consistency can be monitored and measured using specific evaluation mechanisms.European Union's Seventh Framework Programme ([FP7/2007-2013]) under grant agreement No. ICT- 215248 and from Queen Mary University of London

Content and Context-Aware Interfaces for Smarter Media Control

Since the arrival of the computer at home during the '80s, the importance of the digital world in our daily lives has hugely increased. First centralized on a unique computer, the digital world spread over several devices that surround us: smartphones, tablets, cameras, music players, etc. However, despite the increasing number of devices around our digital lives, the way we interact with them has barely evolved. Digital devices are not aware of their surrounding environment, and they often use interfaces and mechanisms which are computer-oriented. The next step in the evolution of our digital life will be centered on a better integration of the digital world with the ecosystem of devices that surrounds it. In this work, we illustrate this upcoming evolution through the development and evaluation of original interfaces dedicated to the control of digital media. Based on our research, we organize these interfaces in three areas of improvement: unification, automation and familiarity. This thesis is divided in four main chapters. The first chapter presents the evolution of our digital world over the last 30 years. The next three chapters are centered on the three areas of improvement that we defined: unification, automation and familiarity. Unification corresponds to the fusion of digital worlds as a unique and coherent whole that devices should interact with. Automation consists in using information obtained from the user and her environment in order to simplify or automate the interaction with the digital world. Finally, familiarity allows benefiting of users' past experiences in order to create friendly and intuitive interfaces

The mobile information access experience - A user perspective

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Mobile technologies, such as mobile phones, smartphones and Palmtop computers, are in an upwards trend and earliest models of such devices are already available to end-users to communicate and access multimedia content on-the-move. As a logical outcome of this development in mobile technologies and devices, content provider companies have already started investing and piloting mobile multimedia content distribution and broadcasting technologies. Nevertheless, no matter how cutting-edge technology is and no matter how stylish the mobile devices are, the ultimate success of wireless communication technologies and devices are directly associated with the user adoption and embrace of these new equipment and technologies. In this perspective, since multimedia content, for mobile or not, is ultimately produced for the education and/or enjoyment of viewers, the user's perspective concerning the presentation quality is surely of equal importance as objective Quality of Service (QoS) technical parameters, to defining distributed multimedia quality. In order to comprehensively understand user experiences whilst accessing information using mobile devices and technologies, we investigate user-mobile device interaction and look into the surrounding issues in a uniform manner by combining multiple aspects: user initial device experience (Out-of-Box Experience), mobile information access in a real-world context, device impact on user information access and perceptually tailored multimedia content impact on user information assimilation and satisfaction. Accordingly, an extensive experimental investigation has been undertaken to see how user experiences varied based on device familiarity, device type, real-world context and variable locations. The findings has shown that the overall perception, and effectively the user information access experience, is affected and improved when multimedia content is tailored according to user device type and context. Thus highlights that the future of mobile computing necessitates two-faceted research, which should combine both a user as well as a technical perspective

Mobile telecommunication networks and mobile commerce : towards its applications in chinese market

La télécommunication mobile connecte les personnes de n'importe où à tout moment. La transmission de la voix et des données à travers les réseaux de télécommunication mobile permet d'envoyer des informations et de diriger des transactions d'une manière nouvelle. Cela crée un nouveau domaine d'affaires qui s'appelle du commerce mobile, une affaire étendue basée sur l'Internet avec de nombreux des caractéristiques uniques ajoutés. Comme un soutien fondamental du plate-forme, les réseaux de la télécommunication mobile joue un rôle essentiel dans le commerce mobile. Leurs caractéristiques techniques et le déploiement déterminent l'essence pour le commerce mobile. Dans cette mémoire, nous étudions et présentons les caractéristiques techniques des technologies communications mobiles du réseau 1G à 3G et au-delà. Nous étudions également les technologies WLAN et WAP qui sont courantes dans le commerce mobile en Chine et dans le monde. Le commerce mobile est en train de se développer, le nombre d'utilisateurs de téléphones mobiles sont de plus en plus en Chine et dans ce monde. Les utilisateurs mobiles énormes en Chine ainsi que la maturité des technologies 3G affichent un fort potentiel pour offrir et d'adopter plus les nouveaux services mobiles. Après réviser l'évolution du commerce mobile et l'histoire du succès i-mode au Japon, nous nous concentrons sur le mobile du marché chinois de manière à découvrir son marché, l'infrastructure du réseau mobile, et le modèle d'affaires. Fondé sur la base de notre enquête sur le commerce mobile chinois, nous présentons, selon notre jugement, les services mobiles et des applications que sont convenables pour la Chine. Parmi eux, nous pensons qu'il y a la tendance sur les services basés sur la localisation et services orientées de l'architectures. Cette tendance peut attirer plus d'attention à offrir de nouveaux services. En plus, elle peut offrir des services d'intégration et de personnalisation qui viennent de fournisseurs de services mobiles et des utilisateurs finaux. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Gestion intégrée et écosystémique, Principe de précaution, Communication entre acteurs, Risques sur l'environnement et la santé

Study, Analysis and Modeling of IP Multimedia systems on next generation networks providing mobile and fixed multimedia services

Not availabl

ARTiVIS Arts, real-time video and interactivity for sustainability

Dissertação para obtenção do Grau de Doutor em Media DigitaisPortuguese Foundation for Science and Technology (SFRH/BD/42555/2007