Game-theoretical design of an adaptive distributed dissemination protocol for VANETs

Road safety applications envisaged for Vehicular Ad Hoc Networks (VANETs) depend largely on the dissemination of warning messages to deliver information to concerned vehicles. The intended applications, as well as some inherent VANET characteristics, make data dissemination an essential service and a challenging task in this kind of networks. This work lays out a decentralized stochastic solution for the data dissemination problem through two game-theoretical mechanisms. Given the non-stationarity induced by a highly dynamic topology, diverse network densities, and intermittent connectivity, a solution for the formulated game requires an adaptive procedure able to exploit the environment changes. Extensive simulations reveal that our proposal excels in terms of number of transmissions, lower end-to-end delay and reduced overhead while maintaining high delivery ratio, compared to other proposalsPeer ReviewedPostprint (published version

Multimedia communications in vehicular adhoc networks for several applications in the smart cities

[EN] Road safety applications envisaged for vehicular ad hoc networks (VANETs) depend largely on the exchange of messages to deliver information to concerned vehicles. Safety applications as well as inherent VANET characteristics make data dissemination an essential service and a challenging task. We are developing a decentralized efficient solution for broadcast data dissemination through two game-theoretical mechanisms. Besides, VANETs can also include autonomous vehicles (AVs). AVs might represent a revolutionary new paradigm that can be a reality in our cities in the next few years. AVs do not need a driver to work; instead, they should copy a proper human behavior to adapt the driving according to the current circumstances, such as speed limit, pedestrian crossing street or wheather conditions. We will develop an AV software module including artificial intelligence (AI) techniques so that AVs can interact with the dynamic scenario throughout time. Finally, we also will include electrical vehicles (EV) in the VANET, so that special services such as finding and reserving an EV charging station place will be welcome. In addition, we are developing a multimetric geographic routing protocol for VANETs to transmit H.265 video (traffic accident, traffic state, commercial….) over VANETs.This work was partly supported by the Spanish Government through the project TEC2014-54335-C4- 1-R INcident monitoRing In Smart COmmunities, QoS and Privacy (INRISCO). Cristian Iza is recipient of a grant from Secretaria Nacional de Educación Superior, Ciencia y Tecnología SENESCYT. Ahmad Mohamad Mezher is a postdoctoral researcher with the Information Security Group (ISG) at the Universitat Politècnica de Catalunya (UPC).Iza Paredes, C.; Uribe Ramírez, JA.; López Márquez, N.; Lemus, L.; Mezher, A.; Aguilar Igartua, M. (2018). Multimedia communications in vehicular adhoc networks for several applications in the smart cities. Editorial Universitat Politècnica de València. 212-215. https://doi.org/10.4995/JITEL2017.2017.6584OCS21221

Implementación de un servicio de streaming de vídeo sobre una plataforma IMS utilizando software libre

La penetración del internet banda ancha, el gran incremento de los terminales inteligentes y la convergencia de las infraestructuras en torno a IP están provocando un cambio radical en el sector de las Telecomunicaciones. En este nuevo panorama, la tecnología IMS (IP Multimedia Subsystem) juega un papel clave. Los usuarios han aumentado sus exigencias y los operadores han visto la necesidad de adaptarse ante estas nuevas exigencias. Las Redes de Siguiente Generación (Next Generation Networks: NGN) proponen solucionar estas exigencias al migrar al modelo de Plataforma de Entrega de Servicios. El proyecto de Tesis presenta la plataforma IP Multimedia Subsystem (IMS) cómo una Plataforma de Entrega de Servicios en la adopción de redes NGN. Este documento detalla la construcción de un prototipo de maqueta IMS. Además describe el diseño e implementación del servicio Streaming de Video usando los bloques de servicio proporcionado por el prototipo. Este trabajo analiza la relación entre los conceptos teóricos y la experiencia práctica de gestionar una plataforma IMS

Evaluating video dissemination in realistic urban vehicular ad-hoc networks

Video content delivery for vehicular ad hoc networks (VANETs) is envisioned to be of high benefit for road safety, traffic management as well as for providing value-added vehicle services. In this paper, we evaluate five existing dissemination mechanisms in a realistic urban scenario. We also propose RCP+ as a renovated mechanism for adaptative video streaming over VANETs. RCP+ is a cross layer dissemination mechanism for video safety messages that specifically addresses urban scenarios with zero infrastructure support. Through simulations, we compare our proposal with other distributed dissemination mechanisms. The performance evaluation shows that our proposal mechanism is more suitable for video transmission in realistic urban scenarios. The results also indicate that a modified frame coding approach provides many opportunities for multimedia services.Peer Reviewe

Adaptive video-streaming dissemination in realistic highway vehicular ad-hoc networks

The dissemination of video information contents migth enhance the performances of safety-related applications in vehicular ah-hoc networks (VANETs). A major problem concerns the high sensitivity of the compressed video streams to the severe channel conditions in wireless ad-hoc networks. The reliable dissemination of video contents in mobile environments is recognized as one of the main challenges for the developing and deploying of VANETs. To improve the robustness of dissemination, we propose RCP+ (Road-Casting Protocol) scheme for distributing high-definition video contents in VANETs. RCP+ is a cross layer dissemination mechanism for video safety messages that specifically addresses highway scenarios with zero infrastructure support. Also, a comparison of one of the most popular and widely spread video encoder H.264/AVC with respect to the recently released video coding scheme H.265/HEVC is presented. The comparison is performed by means of simulations showing differences between encoding algorithms in terms of perceived quality. The results indicate a better performance of HEVC based encoding algorithm in comparison to AVC in VANET environments.Peer Reviewe

Evaluating video dissemination in realistic urban vehicular ad-hoc networks

Video content delivery for vehicular ad hoc networks (VANETs) is envisioned to be of high benefit for road safety, traffic management as well as for providing value-added vehicle services. In this paper, we evaluate five existing dissemination mechanisms in a realistic urban scenario. We also propose RCP+ as a renovated mechanism for adaptative video streaming over VANETs. RCP+ is a cross layer dissemination mechanism for video safety messages that specifically addresses urban scenarios with zero infrastructure support. Through simulations, we compare our proposal with other distributed dissemination mechanisms. The performance evaluation shows that our proposal mechanism is more suitable for video transmission in realistic urban scenarios. The results also indicate that a modified frame coding approach provides many opportunities for multimedia services.Peer Reviewe

Performance evaluation of dissemination protocols for emergency messages in Vehicular Ad-Hoc networks

Road safety applications envisaged for VANETs depend largely on the exchange of messages to deliver information to the concerned vehicles. In the last years, several dissemination protocols have been presented in the literature. In this paper we study and evaluate the dissemination of emergency messages in realistic vehicular scenarios. In the evaluation, some protocols are examined from two perspectives: qualitative and quantitative. We identify the principal mechanisms of dissemination and examine the factors that most impact on the simulation results. In addition, we investigate the effects of the shadows of buildings and other vehicles in the performance of the dissemination protocols. The simulation results suggest the need to include scenarios with fixed and mobile obstacles to increase the credibility of the performance of the evaluated protocols.Peer Reviewe

Game-theoretical design of an adaptive distributed dissemination protocol for VANETs

Road safety applications envisaged for Vehicular Ad Hoc Networks (VANETs) depend largely on the dissemination of warning messages to deliver information to concerned vehicles. The intended applications, as well as some inherent VANET characteristics, make data dissemination an essential service and a challenging task in this kind of networks. This work lays out a decentralized stochastic solution for the data dissemination problem through two game-theoretical mechanisms. Given the non-stationarity induced by a highly dynamic topology, diverse network densities, and intermittent connectivity, a solution for the formulated game requires an adaptive procedure able to exploit the environment changes. Extensive simulations reveal that our proposal excels in terms of number of transmissions, lower end-to-end delay and reduced overhead while maintaining high delivery ratio, compared to other proposalsPeer Reviewe

Techniques for underwater photographic examination of irradiated nuclear fuel

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