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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
Avoiding Interruptions - QoE Trade-offs in Block-coded Streaming Media Applications
We take an analytical approach to study Quality of user Experience (QoE) for
video streaming applications. First, we show that random linear network coding
applied to blocks of video frames can significantly simplify the packet
requests at the network layer and save resources by avoiding duplicate packet
reception. Network coding allows us to model the receiver's buffer as a queue
with Poisson arrivals and deterministic departures. We consider the probability
of interruption in video playback as well as the number of initially buffered
packets (initial waiting time) as the QoE metrics. We characterize the optimal
trade-off between these metrics by providing upper and lower bounds on the
minimum initial buffer size, required to achieve certain level of interruption
probability for different regimes of the system parameters. Our bounds are
asymptotically tight as the file size goes to infinity.Comment: Submitted to ISIT 2010 - Full versio
On Counteracting Byzantine Attacks in Network Coded Peer-to-Peer Networks
Random linear network coding can be used in peer-to-peer networks to increase
the efficiency of content distribution and distributed storage. However, these
systems are particularly susceptible to Byzantine attacks. We quantify the
impact of Byzantine attacks on the coded system by evaluating the probability
that a receiver node fails to correctly recover a file. We show that even for a
small probability of attack, the system fails with overwhelming probability. We
then propose a novel signature scheme that allows packet-level Byzantine
detection. This scheme allows one-hop containment of the contamination, and
saves bandwidth by allowing nodes to detect and drop the contaminated packets.
We compare the net cost of our signature scheme with various other Byzantine
schemes, and show that when the probability of Byzantine attacks is high, our
scheme is the most bandwidth efficient.Comment: 26 pages, 9 figures, Submitted to IEEE Journal on Selected Areas in
Communications (JSAC) "Mission Critical Networking
Multiple-Tree Push-based Overlay Streaming
Multiple-Tree Overlay Streaming has attracted a great amount of attention
from researchers in the past years. Multiple-tree streaming is a promising
alternative to single-tree streaming in terms of node dynamics and load
balancing, among others, which in turn addresses the perceived video quality by
the streaming user on node dynamics or when heterogeneous nodes join the
network. This article presents a comprehensive survey of the different
aproaches and techniques used in this research area. In this paper we identify
node-disjointness as the property most approaches aim to achieve. We also
present an alternative technique which does not try to achieve this but does
local optimizations aiming global optimizations. Thus, we identify this
property as not being absolute necessary for creating robust and heterogeneous
multi-tree overlays. We identify two main design goals: robustness and support
for heterogeneity, and classify existing approaches into these categories as
their main focus
Access-Network Association Policies for Media Streaming in Heterogeneous Environments
We study the design of media streaming applications in the presence of
multiple heterogeneous wireless access methods with different throughputs and
costs. Our objective is to analytically characterize the trade-off between the
usage cost and the Quality of user Experience (QoE), which is represented by
the probability of interruption in media playback and the initial waiting time.
We model each access network as a server that provides packets to the user
according to a Poisson process with a certain rate and cost. Blocks are coded
using random linear codes to alleviate the duplicate packet reception problem.
Users must take decisions on how many packets to buffer before playout, and
which networks to access during playout. We design, analyze and compare several
control policies with a threshold structure. We formulate the problem of
finding the optimal control policy as an MDP with a probabilistic constraint.
We present the HJB equation for this problem by expanding the state space, and
exploit it as a verification method for optimality of the proposed control law.Comment: submitted to CDC 201
VOD STREAMING WITH A NETWORK CODING EQUIVALENT CONTENT DISTRIBUTION SCHEME
Although random access operations are desirable for on-demand video streaming in peer-to-peer systems, they are difficult to efficiently achieve due to the asynchronous interactive behaviors of users and the dynamic nature of peers. In this paper, we propose a network coding equivalent content distribution (NCECD) scheme to efficiently handle interactive videoon- demand (VoD) operations in peer-to-peer systems. In NCECD, videos are divided into segments that are then further divided into blocks. These blocks are encoded into independent blocks that are distributed to different peers for local storage. With NCECD, a new client only needs to connect to a sufficient number of parent peers to be able to view the whole video and rarely needs to find new parents when performing random access operations. In most existing methods, a new client must search for parent peers containing specific segments; however, NCECD uses the properties of network coding to cache equivalent content in peers, so that one can pick any parent without additional searches. Experimental results show that the proposed scheme achieves low startup and jump searching delays and requires fewer server resources. In addition, we present the analysis of system parameters to achieve reasonable block loss rates for the proposed scheme
Video-on-Demand over Internet: a survey of existing systems and solutions
Video-on-Demand is a service where movies are delivered to distributed users with low delay and free interactivity. The traditional client/server architecture experiences scalability issues to provide video streaming services, so there have been many proposals of systems, mostly based on a peer-to-peer or on a hybrid server/peer-to-peer solution, to solve this issue. This work presents a survey of the currently existing or proposed systems and solutions, based upon a subset of representative systems, and defines selection criteria allowing to classify these systems. These criteria are based on common questions such as, for example, is it video-on-demand or live streaming, is the architecture based on content delivery network, peer-to-peer or both, is the delivery overlay tree-based or mesh-based, is the system push-based or pull-based, single-stream or multi-streams, does it use data coding, and how do the clients choose their peers. Representative systems are briefly described to give a summarized overview of the proposed solutions, and four ones are analyzed in details. Finally, it is attempted to evaluate the most promising solutions for future experiments. Résumé La vidéo à la demande est un service où des films sont fournis à distance aux utilisateurs avec u
An Optimized AMS Based Cloud Downloading Service with Advanced Caching and Intelligent Data Distribution Mechanism
The popularity of peer-to-peer video content downloading has surged due to diverse content availability and convenient sharing among users. However, scaling systems to accommodate the growing number of users and content items poses a challenge. This research aims to optimize video content downloading in peer-to-peer systems. The objective is to improve performance by developing advanced caching mechanisms, an intelligent data distribution algorithm, and efficient bandwidth resource management. The proposed approach involves implementing innovative caching mechanisms that store frequently accessed content closer to users, reducing download time. An intelligent data distribution algorithm minimizes bottlenecks and maximizes download speeds. Efficient bandwidth resource management ensures fair allocation. Results demonstrate significant enhancements in download time and overall system performance, leading to improved user experience. This research addresses the need for an optimized video content downloading system to handle increasing user and content volumes. The findings hold the potential to enhance user experiences, facilitate seamless video sharing, and advance peer-to-peer video content downloading
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