Supporting real time video transmission over wireless networks is very challenging. The video flow characteristics can be vulnerable to the time-varying channel conditions and the unreliability of the MAC (Medium Access Control) can substantially degrade Quality of Experience (QoE) in wireless networks. QoE reflects the satisfaction level of a user towards a particular service or application. It can be a valuable input to service providers and help them to enhance the quality of the overall system. In this work, we present a methodology and a system based on Random Neural Network (RNN) to analyze the impact of different MAC-level parameters on video QoE over IEEE 802.11n wireless networks. At first, subjective tests are performed to correlate MAC-level parameters with user's perceived video QoE. Secondly, we propose a RNN technique to estimate the impact of these parameters on video QoE. The experimental results show that the proposed method can effectively measure the impact of MAC-level parameters on video QoE. The acceptable correlation between subjective QoE and estimated QoE verifies the validity of the obtained results.

Estimation of video QoE from MAC parameters in wireless network: A Random Neural Network approach

The IEEE 802.11aa amendment standardised the Group Addressed Transmission Service (GATS), which extends 802.11 WLANs with a novel set of MAC mechanisms to support an effective and efficient multicast video service. The key challenge with GATS is the selection of the best scheme and its configuration for a given network scenario, as the standard does not provide any guidelines nor any assessment of the performance of each mechanism. Although some previous studies have addressed this challenge, their evaluation is either via analysis or simulations under non-realistic assumptions, or based on Quality of Service (QoS) metrics instead of video quality metrics, which are required for a proper video performance assessment. In this paper, we deploy a mid-size real-life testbed and develop a thoughtful methodology to perform an extensive Quality of Experience (QoE) evaluation of GATS under a variety of scenarios. We analyse the performance of the novel schemes under ideal conditions, as well as under controlled and non-controlled interference, assessing their ability to provide an adequate QoE and quantifying the resources left for other type of traffic. Ours is the first thorough QoE evaluation of GATS in a real-life scenario, providing key insights on their performance, and can be used to derive configuration guidelines for the schemes.

Experimental QoE Evaluation of Multicast Video Delivery over IEEE 802.11aa WLANs

Real time video transmission over wireless networks is very challenging due to the time-varying channel conditions and video flow characteristics. Quality of experience (QoE) in multimedia traffic has been the focus of extensive research in the recent years. It reflects user's satisfaction towards a particular service and provides valuable input to the service providers to determine the quality of the overall system. QoE estimation is challenging as it tries to measure a subjective metric where user experience depends on a number of factors that cannot simply be measured. In this paper, the impact of different MAC-level parameters on video QoE over IEEE 802.11n wireless networks is analyzed. Subjective tests to correlate MAC-level parameters with perceived QoE of video traffic were performed. We considered different types of video for the evaluation. The study shows that careful parameterization of MAC-level parameters can improve the QoE for video streaming applications when used over a wireless networks.

Performance evaluation of video transmission over 802.11n wireless network: A MAC layer perspective

De nos jours, l’experience de l'utilisateur appele en anglais « User Experience » est devenue l’un des indicateurs les plus pertinents pour les fournisseurs de services ainsi que pour les operateurs de telecommunication pour analyser le fonctionnement de bout en bout de leurs systemes (du terminal client, en passant par le reseaux jusqu’a l’infrastructure des services etc.). De plus, afin d’entretenir leur part de marche et rester competitif, les differents operateurs de telecommunication et les fournisseurs de services doivent constamment conserver et accroitre le nombre de souscription des clients. Pour repondre a ces exigences, ils doivent disposer de solutions efficaces de monitoring et d’estimation de la qualite d'experience (QoE) afin d’evaluer la satisfaction de leur clients. Cependant, la QoE est une mesure qui reste subjective et son evaluation est couteuse et fastidieuse car elle necessite une forte participation humaine (appele panel de d’evaluation). Par consequent, la conception d’un outil qui peut mesurer objectivement cette qualite d'experience avec une precision raisonnable et en temps reel est devenue un besoin primordial qui constitue un challenge interessant a resoudre. Comme une premiere contribution, nous avons analyse l'impact du comportement d’un reseau sur la qualite des services de video a la demande (VOD). Nous avons egalement propose un outil d'estimation objective de la QoE qui utilise le systeme expert base sur la logique floue pour evaluer la QoE a partir des parametres de qualite de service de la couche reseau. Dans une deuxieme contribution, nous avons analyse l'impact des parametres QoS de couche MAC sur les services de VoD dans le cadre des reseaux sans fil IEEE 802.11n. Nous avons egalement propose un outil d'estimation objective de la QoE qui utilise le reseau aleatoire de neurones pour estimer la QoE dans la perspective de la couche MAC. Pour notre troisieme contribution, nous avons analyse l'effet de differents scenarios d'adaptation sur la QoE dans le cadre du streaming adaptatif au debit. Nous avons egalement developpe une plate-Forme Web de test subjectif qui peut etre facilement integre dans une plate-Forme de crowd-Sourcing pour effectuer des tests subjectifs. Finalement, pour notre quatrieme contribution, nous avons analyse l'impact des differents parametres de qualite de service Web sur leur QoE. Nous avons egalement propose un algorithme d'apprentissage automatique i.e. un systeme expert hybride rugueux base sur la logique floue pour estimer objectivement la QoE des Web services

https://tel.archives-ouvertes.fr/tel-01149696/document

Intelligent quality of experience (QoE) analysis of network served multimedia and web contents

With the fast expansion of a variety of multimedia technologies, further and more multimedia statistics are produced and transmitted in the fields like military, medical and for further commercial field which may have some susceptible information that is not to be supposed to be seen or accessed by or may only be shown partially to the common users Therefore, security and privacy has turn out to be significant phase Over the last few years numerous encryption algorithms are introduced to secure and protect the video during transmission Along with that many efficient multimedia encryption schemes are introduced and real world is using those techniques In this paper, various techniques are observed described showing encryption methods and video transmission techniques have been studied

/pdf/a-technical-survey-based-on-secure-video-transmission-2702emy1k7.pdf

A Technical Survey based on Secure Video Transmission Techniques

The massive acceptance of the high data rate IEEE 802.11n standard enables the adoption of demanding audiovisual services, such as high definition TV over wireless local area networks. In this context, one of the key features of the IEEE 802.11n is the frame aggregation mechanism, which can improve the channel efficiency and data throughput. In this work, the efficiency of video transmissions schemes over 802.11n wireless networks is studied. The focus is centered on the new features introduced at the MAC layer of IEEE 802.11n such as frame aggregation, still considering the advances made in physical layer such as multiple input multiple output (MIMO). In addition, the H.264/AVC video coding standard is exploited to maximize the overall coding efficiency in such wireless network scenario. This study will show that careful parameterization at the MAC and application layers can provide an improve quality of service for many video streaming applications when deployed over an 802.11n network.

Goncalo Barreira

Papers

Impact of the IEEE 802.11n frame aggregation mechanisms on video streaming quality