Real-time Group Video Sharing tied with Online Social Networks

The exploding growth of OSNs (Online Social Networks) is a common trend incurrent mobile Internet era. In this paper, by linking the features of Facebook OSN andMOVi+ (Mobile Opportunistic Video-on-demand Plus) [1-3], we realize real-time P2P videosharing among mobile nodes. The realized prototype implementation clearly verifies theconvenience and economic feasibility of OSN-initiated application development

Mobile Video Streaming Applications: A Systematic Review of Test Metrics in Usability Evaluation

In evaluating the usability of mobile video streaming applications, the performance of the applications comes into focus. This is because the performance of mobile streaming applications affects their usability. From this study, video streaming and video quality are identified as the two most evaluated elements in the usability test of mobile video streaming applications. These elements are affected by several related factors that are peculiar to the mobile platforms and domains. These in turn affect the usability of the applications. In mobile platforms, bandwidth is low and network connections are unstable; this is coupled with the limitations caused by the smallness of the screen sizes of the mobile devices. Furthermore, startup delays, jitter, latency and rebuffering are the determining factors for the performance of mobile video streaming. On the other hand, video quality is determined by frame rate, bit rate, and resolution. These factors present themselves due to the mobile context of mobile streaming applications. They combine to influence the performance of the applications as well as their usability. Therefore, in considering the usability of these set of applications, these factors (metrics) are important as they determine the performance of the applications and by and large also affect the usability of the applications. Other factors identified in the study that affect the usability of mobile streaming applications include: functionality, social context and user interface and appearance. On the whole, this paper presents the results of a systematic review of test metrics in the usability evaluation of mobile video streaming applications. The systematic review approach used include: defining the search strategy, selection of primary studies, the extraction of data, and the implementation of a synthesis strategy. Using this methodology, 238 studies were found; however, only 51 relevant studies were eventually selected for the review. The study reveals that time taken for video streaming and the video quality were the two most popular metrics used in the usability test and evaluation of mobile video streaming applications. Besides, most of the studies concentrated on the usability of mobile TV as users switch from traditional TV to mobile TV

Mobile video streaming applications: a systematic review of test metrics in usability evaluation

In evaluating the usability of mobile video streaming applications, the performance of the applications comes into focus.This is because the performance of mobile streaming applications affects their usability. From this study, video streaming and video quality are identified as the two most evaluated elements in the usability test of mobile video streaming applications. These elements are affected by several related factors that are peculiar to the mobile platforms and domains. These in turn affect the usability of the applications. In mobile platforms, bandwidth is low and network connections are unstable; this is coupled with the limitations caused by the smallness of the screen sizes of the mobile devices. Furthermore, startup delays, jitter, latency and rebuffering are the determining factors for the performance of mobile video streaming. On the other hand, video quality is determined by frame rate, bit rate, and resolution. These factors present themselves due to the mobile context of mobile streaming applications. They combine to influence the performance of the applications as well as their usability. Therefore, in considering the usability of these set of applications, these factors (metrics) are important as they determine the performance of the applications and by and large also affect the usability of the applications. Other factors identified in the study that affect the usability of mobile streaming applications include: functionality, social context and user interface and appearance. On the whole, this paper presents the results of a systematic review of test metrics in the usability evaluation of mobile video streaming applications. The systematic review approach used include: defining the search strategy, selection of primary studies, the extraction of data, and the implementation of a synthesis strategy. Using this methodology, 238 studies were found; however, only 51 relevant studies were eventually selected for the review. The study reveals that time taken for video streaming and the video quality were the two most popular metrics used in the usability test and evaluation of mobile video streaming applications. Besides, most of the studies concentrated on the usability of mobile TV as users switch from traditional TV to mobile TV

Contributions to Vehicular Communications Systems and Schemes

La dernière décennie a marqué une grande hausse des applications véhiculaires comme une nouvelle source de revenus et un facteur de distinction dans l'industrie des véhicules. Ces applications véhiculaires sont classées en deux groupes : les applications de sécurité et les applications d'info divertissement. Le premier groupe inclue le changement intelligent de voie, l'avertissement de dangers de routes et la prévention coopérative de collision qui comprend la vidéo sur demande (VoD), la diffusion en direct, la diffusion de météo et de nouvelles et les jeux interactifs. Cependant, Il est à noter que d'une part, les applications véhiculaires d'info divertissement nécessitent une bande passante élevée et une latence relativement faible ; D'autre part, les applications de sécurité requièrent exigent un délai de bout en bout très bas et un canal de communication fiable pour la livraison des messages d'urgence. Pour satisfaire le besoin en applications efficaces, les fabricants de véhicules ainsi que la communauté académique ont introduit plusieurs applications à l’intérieur de véhicule et entre véhicule et véhicule (V2V). Sauf que, l'infrastructure du réseau sans fil n'a pas été conçue pour gérer les applications de véhicules, en raison de la haute mobilité des véhicules, de l'imprévisibilité du comportement des conducteurs et des modèles de trafic dynamiques. La relève est l'un des principaux défis des réseaux de véhicules, car la haute mobilité exige au réseau sans fil de faire la relève en un très court temps. De plus, l'imprévisibilité du comportement du conducteur cause l'échec des protocoles proactifs traditionnels de relève, car la prédiction du prochain routeur peut changer en fonction de la décision du conducteur. Aussi, le réseau de véhicules peut subir une mauvaise qualité de service dans les régions de relève en raison d'obstacles naturels, de véhicules de grande taille ou de mauvaises conditions météorologiques. Cette thèse se concentre sur la relève dans l'environnement des véhicules et son effet sur les applications véhiculaires. Nous proposons des solutions pratiques pour les réseaux actuellement déployés, principalement les réseaux LTE, l'infrastructure véhicule à véhicule (V2V) ainsi que les outils efficaces d’émulateurs de relèves dans les réseaux véhiculaires.----------ABSTRACT: The last decade marked the rise of vehicular applications as a new source of revenue and a key differentiator in the vehicular industry. Vehicular Applications are classified into safety and infotainment applications. The former include smart lane change, road hazard warning, and cooperative collision avoidance; however, the latter include Video on Demand (VoD), live streaming, weather and news broadcast, and interactive games. On one hand, infotainment vehicular applications require high bandwidth and relatively low latency; on the other hand, safety applications requires a very low end to end delay and a reliable communication channel to deliver emergency messages. To satisfy the thirst for practical applications, vehicle manufacturers along with research institutes introduced several in-vehicle and Vehicle to Vehicle (V2V) applications. However, the wireless network infrastructure was not designed to handle vehicular applications, due to the high mobility of vehicles, unpredictability of drivers’ behavior, and dynamic traffic patterns. Handoff is one of the main challenges of vehicular networks since the high mobility puts pressure on the wireless network to finish the handoff within a short period. Moreover, the unpredictability of driver behavior causes the traditional proactive handoff protocols to fail, since the prediction of the next router may change based on the driver’s decision. Moreover, the vehicular network may suffer from bad Quality of Service (QoS) in the regions of handoff due to natural obstacles, large vehicles, or weather conditions. This thesis focuses on the handoff on the vehicular environment and its effect on the vehicular applications. We consider practical solutions for the currently deployed networks mainly Long Term Evolution (LTE) networks, the Vehicle to Vehicle (V2V) infrastructure, and the tools that can be used effectively to emulate handoff on the vehicular networks