Multimedia delivery in the future internet

The term “Networked Media” implies that all kinds of media including text, image, 3D graphics, audio and video are produced, distributed, shared, managed and consumed on-line through various networks, like the Internet, Fiber, WiFi, WiMAX, GPRS, 3G and so on, in a convergent manner [1]. This white paper is the contribution of the Media Delivery Platform (MDP) cluster and aims to cover the Networked challenges of the Networked Media in the transition to the Future of the Internet. Internet has evolved and changed the way we work and live. End users of the Internet have been confronted with a bewildering range of media, services and applications and of technological innovations concerning media formats, wireless networks, terminal types and capabilities. And there is little evidence that the pace of this innovation is slowing. Today, over one billion of users access the Internet on regular basis, more than 100 million users have downloaded at least one (multi)media file and over 47 millions of them do so regularly, searching in more than 160 Exabytes1 of content. In the near future these numbers are expected to exponentially rise. It is expected that the Internet content will be increased by at least a factor of 6, rising to more than 990 Exabytes before 2012, fuelled mainly by the users themselves. Moreover, it is envisaged that in a near- to mid-term future, the Internet will provide the means to share and distribute (new) multimedia content and services with superior quality and striking flexibility, in a trusted and personalized way, improving citizens’ quality of life, working conditions, edutainment and safety. In this evolving environment, new transport protocols, new multimedia encoding schemes, cross-layer inthe network adaptation, machine-to-machine communication (including RFIDs), rich 3D content as well as community networks and the use of peer-to-peer (P2P) overlays are expected to generate new models of interaction and cooperation, and be able to support enhanced perceived quality-of-experience (PQoE) and innovative applications “on the move”, like virtual collaboration environments, personalised services/ media, virtual sport groups, on-line gaming, edutainment. In this context, the interaction with content combined with interactive/multimedia search capabilities across distributed repositories, opportunistic P2P networks and the dynamic adaptation to the characteristics of diverse mobile terminals are expected to contribute towards such a vision. Based on work that has taken place in a number of EC co-funded projects, in Framework Program 6 (FP6) and Framework Program 7 (FP7), a group of experts and technology visionaries have voluntarily contributed in this white paper aiming to describe the status, the state-of-the art, the challenges and the way ahead in the area of Content Aware media delivery platforms

Multipath streaming: fundamental limits and efficient algorithms

We investigate streaming over multiple links. A file is split into small units called chunks that may be requested on the various links according to some policy, and received after some random delay. After a start-up time called pre-buffering time, received chunks are played at a fixed speed. There is starvation if the chunk to be played has not yet arrived. We provide lower bounds (fundamental limits) on the starvation probability of any policy. We further propose simple, order-optimal policies that require no feedback. For general delay distributions, we provide tractable upper bounds for the starvation probability of the proposed policies, allowing to select the pre-buffering time appropriately. We specialize our results to: (i) links that employ CSMA or opportunistic scheduling at the packet level, (ii) links shared with a primary user (iii) links that use fair rate sharing at the flow level. We consider a generic model so that our results give insight into the design and performance of media streaming over (a) wired networks with several paths between the source and destination, (b) wireless networks featuring spectrum aggregation and (c) multi-homed wireless networks.Comment: 24 page

LTE Optimization and Resource Management in Wireless Heterogeneous Networks

Mobile communication technology is evolving with a great pace. The development of the Long Term Evolution (LTE) mobile system by 3GPP is one of the milestones in this direction. This work highlights a few areas in the LTE radio access network where the proposed innovative mechanisms can substantially improve overall LTE system performance. In order to further extend the capacity of LTE networks, an integration with the non-3GPP networks (e.g., WLAN, WiMAX etc.) is also proposed in this work. Moreover, it is discussed how bandwidth resources should be managed in such heterogeneous networks. The work has purposed a comprehensive system architecture as an overlay of the 3GPP defined SAE architecture, effective resource management mechanisms as well as a Linear Programming based analytical solution for the optimal network resource allocation problem. In addition, alternative computationally efficient heuristic based algorithms have also been designed to achieve near-optimal performance

Prise de décision de handover vertical pour la gestion de mobilité dans les réseaux hétérogènes sans fil

L évolution des technologies réseaux sans fil, des terminaux mobiles ainsi que des contenus et des services créent des environnements hétérogènes de plus en plus complexes. Dans ce contexte, un compromis entre la mobilité, la transparence et la performance apparaît. Des utilisateurs mobiles, ayant différents profils et préférences, voudraient être toujours connectés au meilleur réseau à tout moment, sans avoir à se soucier des différentes transitions entre réseaux hétérogènes. Face à cette complexité, il parait nécessaire de proposer de nouvelles approches afin de rendre ces systèmes plus autonomes et de rendre les décisions de handover vertical plus efficaces. Cette thèse se concentre sur la gestion de mobilité verticale, plus précisément sur la prise de décision de handover vertical dans un environnement de réseaux hétérogènes sans fil. Après l identification des différents paramètres de prise de décision et l analyse de l état de l art relié à la gestion de la mobilité verticale, nous avons proposé un système de réputation qui permet de réduire les délais de prise de décision. La réputation d un réseau est introduite comme une nouvelle métrique de prise de décision qui peut être recueillie à partir des expériences précédentes des utilisateurs sur ce réseau. Nous montrons que la réputation est une métrique efficace qui permet l anticipation du handover et accélère la prise de décision. Bien que l objectif principal soit de garantir la meilleure qualité de service et l utilisation optimale des ressources radios, les aspects économiques doivent également être considérés, y compris la minimisation des coûts pour les utilisateurs et la maximisation des revenus pour les fournisseurs de services ou les opérateurs. Nous proposons alors, dans la deuxième partie de la thèse, un mécanisme de prise de décision basé sur la théorie des jeux. Ce dernier permet la maximisation des utilités des réseaux et des utilisateurs. Dans cette solution, chaque réseau disponible joue un jeu de Stackelberg avec un ensemble d utilisateurs, tandis que les utilisateurs jouent un jeu de Nash entre eux pour partager les ressources radios limitées. Un point d équilibre de Nash, qui maximise l utilité de l utilisateur et les revenus des fournisseurs de services, est trouvé et utilisé pour le contrôle d admission et la prise de décision de handover vertical. Dans la troisième partie de cette thèse, nous proposons et discutons deux différentes solutions architecturales sur lesquelles nos mécanismes de prise de décision proposés peuvent être intégrés. La première architecture proposée est basée sur la norme IEEE 802.21 à laquelle nous proposons certaines extensions. La seconde architecture proposée est basée sur un niveau de contrôle composé de deux couches de virtualisation. La virtualisation est assurée via des agents capables de faire un raisonnement et de prendre des décisions pour le compte d entités physiques qu ils représentent au sein du système. Cette architecture permet une plus grande flexibilitéMobility management over heterogeneous wireless networks is becoming a major interest area as new technologies and services continue to proliferate within the wireless networking market. In this context, seamless mobility is considered to be crucial for ubiquitous computing. Service providers aim to increase the revenue and to improve users satisfaction. However there are still many technical and architectural challenges to overcome before achieving the required interoperability and coexistence of heterogeneous wireless access networks. Indeed, the context of wireless networks is offering multiple and heterogeneous technologies (e.g. 2G to 4G, WiFi, Wimax, TETRA,...). On the one hand, this rich environment allows users to take profit from different capacities and coverage characteristics. Indeed, this diversity can provide users with high flexibility and allow them to seamlessly connect at any time and any where to the access technology that best fits their requirements. Additionally, cooperation between these different technologies can provide higher efficiency in the usage of the scarce wireless resources offering more economic systems for network providers. On the other hand, the heterogeneity of technologies and architectures and the multiplication of networks and service providers creates a complex environment where cooperation becomes challenging at different levels including and not limited to mobility management, radio resource provisioning, Quality of Service and security guarantees. This thesis is focusing on mobility management and mainly on decision making for Vertical handover within heterogeneous wireless network environments. After the analysis of the related state of the art, we first propose a reputation based approach that allows fast vertical handover decision making. A decision making scheme is then built on that approach. Network s reputation, is a new metric that can be gathered from previous users experiences in the networks. We show that it is an efficient construct to speed up the vertical handover decision making thanks to anticipation functionalities. While the main objective remains guaranteeing the best Quality of Service and optimal radio resource utilization, economical aspects have also to be considered including cost minimization for users and revenue maximization for network providers. For this aim, we propose, in the second part of the thesis, a game theoretic based scheme that allows maximizing benefits for both networks and users. In this solution, each available network plays a Stackelberg game with a finite set of users, while users are playing a Nash game among themselves to share the limited radio resources. A Nash equilibrium point, that maximizes the user s utility and the service provider revenue, is found and used for admission control and vertical handover decision making. The analyses of the optimal bandwidth/prices and the revenue at the equilibrium point show that there are some possible policies to use according to user s requirements in terms of QoS and to network capacities. For instance, we pointed out that networks having same capacities and different reputation values should charge users with different prices which makes reputation management very important to attract users and maximize networks revenue. In the third part of this thesis, we provide and discuss two different architectural and implementation solutions on which our proposed vertical handover decision mechanisms can be integrated. The first proposed architecture is a centralized one. It is based on the IEEE 802.21 standard to which some extensions are proposed. The second proposed architecture is distributed. It is based on an overlay control level composed of two virtualization layers able to make reasoning on behalf of physical entities within the system. This architecture allows higher flexibility especially for loosely coupled interconnected networksEVRY-INT (912282302) / SudocSudocFranceF

Quality-Oriented Mobility Management for Multimedia Content Delivery to Mobile Users

The heterogeneous wireless networking environment determined by the latest developments in wireless access technologies promises a high level of communication resources for mobile computational devices. Although the communication resources provided, especially referring to bandwidth, enable multimedia streaming to mobile users, maintaining a high user perceived quality is still a challenging task. The main factors which affect quality in multimedia streaming over wireless networks are mainly the error-prone nature of the wireless channels and the user mobility. These factors determine a high level of dynamics of wireless communication resources, namely variations in throughput and packet loss as well as network availability and delays in delivering the data packets. Under these conditions maintaining a high level of quality, as perceived by the user, requires a quality oriented mobility management scheme. Consequently we propose the Smooth Adaptive Soft-Handover Algorithm, a novel quality oriented handover management scheme which unlike other similar solutions, smoothly transfer the data traffic from one network to another using multiple simultaneous connections. To estimate the capacity of each connection the novel Quality of Multimedia Streaming (QMS) metric is proposed. The QMS metric aims at offering maximum flexibility and efficiency allowing the applications to fine tune the behavior of the handover algorithm. The current simulation-based performance evaluation clearly shows the better performance of the proposed Smooth Adaptive Soft-Handover Algorithm as compared with other handover solutions. The evaluation was performed in various scenarios including multiple mobile hosts performing handover simultaneously, wireless networks with variable overlapping areas, and various network congestion levels

Experimentation and Characterization of Mobile Broadband Networks

The Internet has brought substantial changes to our life as the main tool to access a large variety of services and applications. Internet distributed nature and technological improvements lead to new challenges for researchers, service providers, and network administrators. Internet traffic measurement and analysis is one of the most trivial and powerful tools to study such a complex environment from different aspects. Mobile BroadBand (MBB) networks have become one of the main means to access the Internet. MBB networks are evolving at a rapid pace with technology enhancements that promise drastic improvements in capacity, connectivity, and coverage, i.e., better performance in general. Open experimentation with operational MBB networks in the wild is currently a fundamental requirement of the research community in its endeavor to address the need for innovative solutions for mobile communications. There is a strong need for objective data relating to stability and performance of MBB (e.g., 2G, 3G, 4G, and soon-to-come 5G) networks and for tools that rigorously and scientifically assess their performance. Thus, measuring end user performance in such an environment is a challenge that calls for large-scale measurements and profound analysis of the collected data. The intertwining of technologies, protocols, and setups makes it even more complicated to design scientifically sound and robust measurement campaigns. In such a complex scenario, the randomness of the wireless access channel coupled with the often unknown operator configurations makes this scenario even more challenging. In this thesis, we introduce the MONROE measurement platform: an open access and flexible hardware-based platform for measurements on operational MBB networks. The MONROE platform enables accurate, realistic, and meaningful assessment of the performance and reliability of MBB networks. We detail the challenges we overcame while building and testing the MONROE testbed and argue our design and implementation choices accordingly. Measurements are designed to stress performance of MBB networks at different network layers by proposing scalable experiments and methodologies. We study: (i) Network layer performance, characterizing and possibly estimating the download speed offered by commercial MBB networks; (ii) End users’ Quality of Experience (QoE), specifically targeting the web performance of HTTP1.1/TLS and HTTP2 on various popular web sites; (iii) Implication of roaming in Europe, understanding the roaming ecosystem in Europe after the "Roam like Home" initiative; and (iv) A novel adaptive scheduler family with deadline is proposed for multihomed devices that only require a very coarse knowledge of the wireless bandwidth. Our results comprise different contributions in the scope of each research topic. To put it in a nutshell, we pinpoint the impact of different network configurations that further complicate the picture and hopefully contribute to the debate about performance assessment in MBB networks. The MBB users web performance shows that HTTP1.1/TLS is very similar to HTTP2 in our large-scale measurements. Furthermore, we observe that roaming is well supported for the monitored operators and the operators using the same approach for routing roaming traffic. The proposed adaptive schedulers for content upload in multihomed devices are evaluated in both numerical simulations and real mobile nodes. Simulation results show that the adaptive solutions can effectively leverage the fundamental tradeoff between the upload cost and completion time, despite unpredictable variations in available bandwidth of wireless interfaces. Experiments in the real mobile nodes provided by the MONROE platform confirm the findings

Exploiting the power of multiplicity: a holistic survey of network-layer multipath

The Internet is inherently a multipath network: For an underlying network with only a single path, connecting various nodes would have been debilitatingly fragile. Unfortunately, traditional Internet technologies have been designed around the restrictive assumption of a single working path between a source and a destination. The lack of native multipath support constrains network performance even as the underlying network is richly connected and has redundant multiple paths. Computer networks can exploit the power of multiplicity, through which a diverse collection of paths is resource pooled as a single resource, to unlock the inherent redundancy of the Internet. This opens up a new vista of opportunities, promising increased throughput (through concurrent usage of multiple paths) and increased reliability and fault tolerance (through the use of multiple paths in backup/redundant arrangements). There are many emerging trends in networking that signify that the Internet's future will be multipath, including the use of multipath technology in data center computing; the ready availability of multiple heterogeneous radio interfaces in wireless (such as Wi-Fi and cellular) in wireless devices; ubiquity of mobile devices that are multihomed with heterogeneous access networks; and the development and standardization of multipath transport protocols such as multipath TCP. The aim of this paper is to provide a comprehensive survey of the literature on network-layer multipath solutions. We will present a detailed investigation of two important design issues, namely, the control plane problem of how to compute and select the routes and the data plane problem of how to split the flow on the computed paths. The main contribution of this paper is a systematic articulation of the main design issues in network-layer multipath routing along with a broad-ranging survey of the vast literature on network-layer multipathing. We also highlight open issues and identify directions for future work