419 research outputs found
Evaluation of unidirectional background push content download services for the delivery of television programs
Este trabajo de tesis presenta los servicios de descarga de contenido en modo push como un
mecanismo eficiente para el envío de contenido de televisión pre-producido sobre redes de
difusión. Hoy en día, los operadores de red dedican una cantidad considerable de recursos
de red a la entrega en vivo de contenido televisivo, tanto sobre redes de difusión como
sobre conexiones unidireccionales. Esta oferta de servicios responde únicamente a
requisitos comerciales: disponer de los contenidos televisivos en cualquier momento y
lugar. Sin embargo, desde un punto de vista estrictamente académico, el envío en vivo es
únicamente un requerimiento para el contenido en vivo, no para contenidos que ya han sido
producidos con anterioridad a su emisión. Más aún, la difusión es solo eficiente cuando el
contenido es suficientemente popular.
Los servicios bajo estudio en esta tesis utilizan capacidad residual en redes de difusión para
enviar contenido pre-producido para que se almacene en los equipos de usuario. La
propuesta se justifica únicamente por su eficiencia. Por un lado, genera valor de recursos de
red que no se aprovecharían de otra manera. Por otro lado, realiza la entrega de contenidos
pre-producidos y populares de la manera más eficiente: sobre servicios de descarga de
contenidos en difusión.
Los resultados incluyen modelos para la popularidad y la duración de contenidos, valiosos
para cualquier trabajo de investigación basados en la entrega de contenidos televisivos.
Además, la tesis evalúa la capacidad residual disponible en redes de difusión, por medio de
estudios empíricos. Después, estos resultados son utilizados en simulaciones que evalúan
las prestaciones de los servicios propuestos en escenarios diferentes y para aplicaciones
diferentes. La evaluación demuestra que este tipo de servicios son un recurso muy útil para
la entrega de contenido televisivo.This thesis dissertation presents background push Content Download Services as an
efficient mechanism to deliver pre-produced television content through existing broadcast
networks. Nowadays, network operators dedicate a considerable amount of network
resources to live streaming live, through both broadcast and unicast connections. This
service offering responds solely to commercial requirements: Content must be available
anytime and anywhere. However, from a strictly academic point of view, live streaming is
only a requirement for live content and not for pre-produced content. Moreover,
broadcasting is only efficient when the content is sufficiently popular.
The services under study in this thesis use residual capacity in broadcast networks to push
popular, pre-produced content to storage capacity in customer premises equipment. The
proposal responds only to efficiency requirements. On one hand, it creates value from
network resources otherwise unused. On the other hand, it delivers popular pre-produced
content in the most efficient way: through broadcast download services.
The results include models for the popularity and the duration of television content,
valuable for any research work dealing with file-based delivery of television content. Later,
the thesis evaluates the residual capacity available in broadcast networks through empirical
studies. These results are used in simulations to evaluate the performance of background
push content download services in different scenarios and for different applications. The
evaluation proves that this kind of services can become a great asset for the delivery of
television contentFraile Gil, F. (2013). Evaluation of unidirectional background push content download services for the delivery of television programs [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/31656TESI
QoE-Based Low-Delay Live Streaming Using Throughput Predictions
Recently, HTTP-based adaptive streaming has become the de facto standard for
video streaming over the Internet. It allows clients to dynamically adapt media
characteristics to network conditions in order to ensure a high quality of
experience, that is, minimize playback interruptions, while maximizing video
quality at a reasonable level of quality changes. In the case of live
streaming, this task becomes particularly challenging due to the latency
constraints. The challenge further increases if a client uses a wireless
network, where the throughput is subject to considerable fluctuations.
Consequently, live streams often exhibit latencies of up to 30 seconds. In the
present work, we introduce an adaptation algorithm for HTTP-based live
streaming called LOLYPOP (Low-Latency Prediction-Based Adaptation) that is
designed to operate with a transport latency of few seconds. To reach this
goal, LOLYPOP leverages TCP throughput predictions on multiple time scales,
from 1 to 10 seconds, along with an estimate of the prediction error
distribution. In addition to satisfying the latency constraint, the algorithm
heuristically maximizes the quality of experience by maximizing the average
video quality as a function of the number of skipped segments and quality
transitions. In order to select an efficient prediction method, we studied the
performance of several time series prediction methods in IEEE 802.11 wireless
access networks. We evaluated LOLYPOP under a large set of experimental
conditions limiting the transport latency to 3 seconds, against a
state-of-the-art adaptation algorithm from the literature, called FESTIVE. We
observed that the average video quality is by up to a factor of 3 higher than
with FESTIVE. We also observed that LOLYPOP is able to reach a broader region
in the quality of experience space, and thus it is better adjustable to the
user profile or service provider requirements.Comment: Technical Report TKN-16-001, Telecommunication Networks Group,
Technische Universitaet Berlin. This TR updated TR TKN-15-00
Modeling And Dynamic Resource Allocation For High Definition And Mobile Video Streams
Video streaming traffic has been surging in the last few years, which has resulted in an increase of its Internet traffic share on a daily basis. The importance of video streaming management has been emphasized with the advent of High Definition: HD) video streaming, as it requires by its nature more network resources. In this dissertation, we provide a better support for managing HD video traffic over both wireless and wired networks through several contributions. We present a simple, general and accurate video source model: Simplified Seasonal ARIMA Model: SAM). SAM is capable of capturing the statistical characteristics of video traces with less than 5% difference from their calculated optimal models. SAM is shown to be capable of modeling video traces encoded with MPEG-4 Part2, MPEG-4 Part10, and Scalable Video Codec: SVC) standards, using various encoding settings. We also provide a large and publicly-available collection of HD video traces along with their analyses results. These analyses include a full statistical analysis of HD videos, in addition to modeling, factor and cluster analyses. These results show that by using SAM, we can achieve up to 50% improvement in video traffic prediction accuracy. In addition, we developed several video tools, including an HD video traffic generator based on our model. Finally, to improve HD video streaming resource management, we present a SAM-based delay-guaranteed dynamic resource allocation: DRA) scheme that can provide up to 32.4% improvement in bandwidth utilization
Design of an adaptive-rate video-streaming service with different classes of users
The provision of end-to-end Quality of Service (QoS) for multimedia services over IP-based networks is already an open issue. To achieve this goal, service providers need to manage Service Level Agreements (SLAs), which specify parameters of the services operation such as availability and performance. Additional mechanisms are needed to quantitatively evaluate the user-level SLA parameters. This work is focused on the evaluation and assessment of different design options of an adaptive VoD service providing several classes of users and fulfilling the SLA commitments. Based on a straightforward Markov Chain, Markov-Reward Chain (MRC) models are developed in order to obtain various QoS measures of the adaptive VoD service. The MRC model has a clear understanding with the design and operation of the VoD system.5th IFIP International Conference on Network Control & Engineering for QoS, Security and MobilityRed de Universidades con Carreras en Informática (RedUNCI
Design of an adaptive-rate video-streaming service with different classes of users
The provision of end-to-end Quality of Service (QoS) for multimedia services over IP-based networks is already an open issue. To achieve this goal, service providers need to manage Service Level Agreements (SLAs), which specify parameters of the services operation such as availability and performance. Additional mechanisms are needed to quantitatively evaluate the user-level SLA parameters. This work is focused on the evaluation and assessment of different design options of an adaptive VoD service providing several classes of users and fulfilling the SLA commitments. Based on a straightforward Markov Chain, Markov-Reward Chain (MRC) models are developed in order to obtain various QoS measures of the adaptive VoD service. The MRC model has a clear understanding with the design and operation of the VoD system.5th IFIP International Conference on Network Control & Engineering for QoS, Security and MobilityRed de Universidades con Carreras en Informática (RedUNCI
ATM network impairment to video quality
Includes bibliographical reference
Recommended from our members
Estimation of LRD present in H.264 video traces using wavelet analysis and proving the paramount of H.264 using OPF technique in wi-fi environment.
While there has always been a tremendous demand for streaming video over
Wireless networks, the nature of the application still presents some challenging
issues. These applications that transmit coded video sequence data over best-effort
networks like the Internet, the application must cope with the changing network
behaviour; especially, the source encoder rate should be controlled based on
feedback from a channel estimator that explores the network intermittently. The
arrival of powerful video compression techniques such as H.264, which advance in
networking and telecommunications, opened up a whole new frontier for multimedia
communications. The aim of this research is to transmit the H.264 coded video
frames in the wireless network with maximum reliability and in a very efficient
manner. When the H.264 encoded video sequences are to be transmitted through
wireless network, it faces major difficulties in reaching the destination. The
characteristics of H.264 video coded sequences are studied fully and their capability
of transmitting in wireless networks are examined and a new approach called
Optimal Packet Fragmentation (OPF) is framed and the H.264 coded sequences are
tested in the wireless simulated environment. This research has three major studies
involved in it. First part of the research has the study about Long Range Dependence
(LRD) and the ways by which the self-similarity can be estimated. For estimating the
LRD a few studies are carried out and Wavelet-based estimator is selected for the
research because Wavelets incarcerate both time and frequency features in the data
and regularly provides a more affluent picture than the classical Fourier analysis.
The Wavelet used to estimate the self-similarity by using the variable called Hurst
Parameter. Hurst Parameter tells the researcher about how a data can behave inside the transmitted network. This Hurst Parameter should be calculated for a more
reliable transmission in the wireless network. The second part of the research deals
with MPEG-4 and H.264 encoder. The study is carried out to prove which encoder is
superior to the other. We need to know which encoder can provide excellent Quality
of Service (QoS) and reliability. This study proves with the help of Hurst parameter
that H.264 is superior to MPEG-4. The third part of the study is the vital part in this
research; it deals with the H.264 video coded frames that are segmented into optimal
packet size in the MAC Layer for an efficient and more reliable transfer in the
wireless network. Finally the H.264 encoded video frames incorporated with the
Optimal Packet Fragmentation are tested in the NS-2 wireless simulated network.
The research proves the superiority of H.264 video encoder and OPF¿s master class
Dynamic bandwidth allocation in ATM networks
Includes bibliographical references.This thesis investigates bandwidth allocation methodologies to transport new emerging bursty traffic types in ATM networks. However, existing ATM traffic management solutions are not readily able to handle the inevitable problem of congestion as result of the bursty traffic from the new emerging services. This research basically addresses bandwidth allocation issues for bursty traffic by proposing and exploring the concept of dynamic bandwidth allocation and comparing it to the traditional static bandwidth allocation schemes
Network emulation focusing on QoS-Oriented satellite communication
This chapter proposes network emulation basics and a complete case study of QoS-oriented Satellite Communication
Design of an adaptive-rate video-streaming service with different classes of users
The provision of end-to-end Quality of Service (QoS) for multimedia services over IP-based networks is already an open issue. To achieve this goal, service providers need to manage Service Level Agreements (SLAs), which specify parameters of the services operation such as availability and performance. Additional mechanisms are needed to quantitatively evaluate the user-level SLA parameters. This work is focused on the evaluation and assessment of different design options of an adaptive VoD service providing several classes of users and fulfilling the SLA commitments. Based on a straightforward Markov Chain, Markov-Reward Chain (MRC) models are developed in order to obtain various QoS measures of the adaptive VoD service. The MRC model has a clear understanding with the design and operation of the VoD system.5th IFIP International Conference on Network Control & Engineering for QoS, Security and MobilityRed de Universidades con Carreras en Informática (RedUNCI
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