Emulation platform design for multimedia applications over vehicular networks

Safety applications seems that will be decisive for a successful introduction to the automotive market for the vehicular networks. However, another kind of applications could be very helpful in order to reach the maximum number of equipped vehicles after market introduction, because can attract a greater number of users and facilitate a vehicular infrastructure investment because vehicular communication must provide business opportunities for Internet service providers to generate revenue. One of these kind of applications is live video streaming over vehicular networks. Video streaming is an attractive feature to many applications, such as emergency live video transmission, video on demand services, road-side video advertisement broadcasting and inter-vehicle video conversation. Test and evaluate implementations in a real testbed environment could be very costly and di cult in this kind of networks. Simulations are still commonly used as a first step in any development for vehicular networks research. Therefore, to test this kind of applications an emulation platform for multimedia applications over vehicular networks is presented in this article. We’ve studied the performance of video streaming services in a infrastructure environment over a highways taking special account in the losses that produces handovers during the communication caused by the network mobility

Emulation platform design for multimedia applications over vehicular networks

Safety applications seems that will be decisive for a successful introduction to the automotive market for the vehicular networks. However, another kind of applications could be very helpful in order to reach the maximum number of equipped vehicles after market introduction, because can attract a greater number of users and facilitate a vehicular infrastructure investment because vehicular communication must provide business opportunities for Internet service providers to generate revenue. One of these kind of applications is live video streaming over vehicular networks. Video streaming is an attractive feature to many applications, such as emergency live video transmission, video on demand services, road-side video advertisement broadcasting and inter-vehicle video conversation. Test and evaluate implementations in a real testbed environment could be very costly and di cult in this kind of networks. Simulations are still commonly used as a first step in any development for vehicular networks research. Therefore, to test this kind of applications an emulation platform for multimedia applications over vehicular networks is presented in this article. We’ve studied the performance of video streaming services in a infrastructure environment over a highways taking special account in the losses that produces handovers during the communication caused by the network mobility

A Comparative Case Study of HTTP Adaptive Streaming Algorithms in Mobile Networks

HTTP Adaptive Streaming (HAS) techniques are now the dominant solution for video delivery in mobile networks. Over the past few years, several HAS algorithms have been introduced in order to improve user quality-of-experience (QoE) by bit-rate adaptation. Their difference is mainly the required input information, ranging from network characteristics to application-layer parameters such as the playback buffer. Interestingly, despite the recent outburst in scientific papers on the topic, a comprehensive comparative study of the main algorithm classes is still missing. In this paper we provide such comparison by evaluating the performance of the state-of-the-art HAS algorithms per class, based on data from field measurements. We provide a systematic study of the main QoE factors and the impact of the target buffer level. We conclude that this target buffer level is a critical classifier for the studied HAS algorithms. While buffer-based algorithms show superior QoE in most of the cases, their performance may differ at the low target buffer levels of live streaming services. Overall, we believe that our findings provide valuable insight for the design and choice of HAS algorithms according to networks conditions and service requirements.Comment: 6 page

EYES : a novel overtaking assistance system for vehicular networks

Developments in the ITS area are received with great expectation by both consumers and industry. Despite their huge potential benefits, ITS solutions suffer from the slow pace of adoption by manufacturers. In this paper we propose EYES, an ITS system that aims at helping drivers in overtaking. The system autonomously creates a network of the devices running EYES, and provides drivers with a video feed from the vehicle located just ahead, thus presenting a better view of any vehicles coming from the opposite direction and the road ahead. This is specially useful when the front view of the driver is blocked by large vehicles, and thus the decision whether to overtake can be taken based on the visuals provided by the application. We have validated EYES, the proposed overtaking assistance system, in both indoor and realistic scenarios involving vehicular network, and preliminary results allow being optimistic about its effectiveness and applicability

Design and analysis of a beacon-less routing protocol for large volume content dissemination in vehicular ad hoc networks

Largevolumecontentdisseminationispursuedbythegrowingnumberofhighquality applications for Vehicular Ad hoc NETworks(VANETs), e.g., the live road surveillance service and the video-based overtaking assistant service. For the highly dynamical vehicular network topology, beacon-less routing protocols have been proven to be efficient in achieving a balance between the system performance and the control overhead. However, to the authors’ best knowledge, the routing design for large volume content has not been well considered in the previous work, which will introduce new challenges, e.g., the enhanced connectivity requirement for a radio link. In this paper, a link Lifetime-aware Beacon-less Routing Protocol (LBRP) is designed for large volume content delivery in VANETs. Each vehicle makes the forwarding decision based on the message header information and its current state, including the speed and position information. A semi-Markov process analytical model is proposed to evaluate the expected delay in constructing one routing path for LBRP. Simulations show that the proposed LBRP scheme outperforms the traditional dissemination protocols in providing a low end-to-end delay. The analytical model is shown to exhibit a good match on the delay estimation with Monte Carlo simulations, as well

Performance tuning of a smartphone-based overtaking assistant

ITS solutions suffer from the slow pace of adoption by manufacturers despite the interest shown by both consumers and industry. Our goal is to develop ITS applications using already available technologies to make them affordable, quick to deploy, and easy to adopt. In this paper we introduce EYES, an overtaking assistance solution that provides drivers with a real-time video feed from the vehicle located just in front. Our application thus provides a better view of the road ahead, and of any vehicles travelling in the opposite direction, being especially useful when the front view of the driver is blocked by large vehicles. We evaluated our application using the MJPEG video encoding format, and have determined the most effective resolution and JPEG quality choice for our case. Experimental results from the tests performed with the application in both indoor and outdoor scenarios, allow us to be optimistic about the effectiveness and applicability of smartphones in providing overtaking assistance based on video streaming in vehicular networks

Service Migration from Cloud to Multi-tier Fog Nodes for Multimedia Dissemination with QoE Support.

A wide range of multimedia services is expected to be offered for mobile users via various wireless access networks. Even the integration of Cloud Computing in such networks does not support an adequate Quality of Experience (QoE) in areas with high demands for multimedia contents. Fog computing has been conceptualized to facilitate the deployment of new services that cloud computing cannot provide, particularly those demanding QoE guarantees. These services are provided using fog nodes located at the network edge, which is capable of virtualizing their functions/applications. Service migration from the cloud to fog nodes can be actuated by request patterns and the timing issues. To the best of our knowledge, existing works on fog computing focus on architecture and fog node deployment issues. In this article, we describe the operational impacts and benefits associated with service migration from the cloud to multi-tier fog computing for video distribution with QoE support. Besides that, we perform the evaluation of such service migration of video services. Finally, we present potential research challenges and trends

Anticipatory Buffer Control and Quality Selection for Wireless Video Streaming

Video streaming is in high demand by mobile users, as recent studies indicate. In cellular networks, however, the unreliable wireless channel leads to two major problems. Poor channel states degrade video quality and interrupt the playback when a user cannot sufficiently fill its local playout buffer: buffer underruns occur. In contrast to that, good channel conditions cause common greedy buffering schemes to pile up very long buffers. Such over-buffering wastes expensive wireless channel capacity. To keep buffering in balance, we employ a novel approach. Assuming that we can predict data rates, we plan the quality and download time of the video segments ahead. This anticipatory scheduling avoids buffer underruns by downloading a large number of segments before a channel outage occurs, without wasting wireless capacity by excessive buffering. We formalize this approach as an optimization problem and derive practical heuristics for segmented video streaming protocols (e.g., HLS or MPEG DASH). Simulation results and testbed measurements show that our solution essentially eliminates playback interruptions without significantly decreasing video quality