Fast and Reliable Emergency Message Dissemination Mechanism in Vehicular Ad-Hoc Networks - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Fast and Reliable Emergency Message Dissemination Mechanism in Vehicular Ad-Hoc Networks write by 王昶升. This book was released on 2009. Fast and Reliable Emergency Message Dissemination Mechanism in Vehicular Ad-Hoc Networks available in PDF, EPUB and Kindle.
Quality of Service Aware Data Dissemination in Vehicular Ad Hoc Networks
Quality of Service Aware Data Dissemination in Vehicular Ad Hoc Networks - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Quality of Service Aware Data Dissemination in Vehicular Ad Hoc Networks write by Mehdi Sharifi Rayeni. This book was released on 2018. Quality of Service Aware Data Dissemination in Vehicular Ad Hoc Networks available in PDF, EPUB and Kindle. Intelligent Transportation Systems (ITS) will be eventually provided in the near future for both safety and comfort of people during their travel on the roads. Vehicular ad-hoc Networks (VANETs), represent the key component of ITS. VANETs consist of vehicles that communicate with each other and with the infrastructure. Indeed, vehicles will be able to exchange messages that include, for example, information about road traffic, emergency situations, and entertainment. Particularly, emergency messages are broadcasted by vehicles in case of an emergency (e.g., car accident); in order to allow drivers to react in time (e.g., slow down), emergency messages must be reliably disseminated with very short delay. In VANETs, there are several factors, such as lossy channel, hidden terminals, interferences and scarce bandwidth, which make satisfying reliability and delay requirements of emergency messages very challenging. In this thesis, as the first contribution, we propose a reliable time-efficient and multi-hop broadcasting scheme, called Dynamic Partitioning Scheme (DPS), to disseminate emergency messages. DPS computes dynamic partition sizes and the transmission schedule for each partition; inside the back area of the sender, the partitions are computed such that in average each partition contains at least a single vehicle; the objective is to ensure that only a vehicle in the farthest partition (from the sender) is used to disseminate the message, to next hop, resulting in shorter one hop delay. DPS ensures fast dissemination of emergency messages. Moreover, a new handshaking mechanism, that uses busy tones, is proposed to solve the problem of hidden terminal problem. In VANETs, Multicasting, i.e. delivering a message from a source to a limited known number of vehicles as destinations, is very important. Compared to Unicasting, with Multicasting, the source can simultaneously support multiple destinations, via a multicast tree, saving bandwidth and reducing overall communication congestion. However, since VANETs have a dynamic topology, maintaining the connectivity of the multicast tree is a major issue. As the second contribution, we propose two approaches to model total bandwidth usage of a multicast tree: (i) the first approach considers the number of road segments involved in the multicast tree and (ii) the second approach considers the number of relaying intersections involved in the multicast tree. A heuristic is proposed for each approach. To ensure QoS of the multicasting tree, efficient procedures are proposed for tracking destinations and monitoring QoS of road segments. As the third contribution, we study the problem of network congestion in routing data traffic in VANETs. We propose (1) a Cloud-based routing approach that, in opposition to existing approaches, takes into account existing routing paths which are already relaying data in VANETs. New routing requests are processed such that no road segment gets overloaded by multiple crossing routing paths. Instead of routing over a limited set of road segments, our approach balances the load of communication paths over the whole urban road segments, with the objective to prevent, whenever possible, local congestions in VANETs; and (2) a Software Defined Networking (SDN) based approach to monitor real-time VANETs connectivity and transmission delays on each road segment. The monitoring data is used as input to the routing approach.
Safety-message Routing in Vehicular Ad Hoc Networks
Safety-message Routing in Vehicular Ad Hoc Networks - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Safety-message Routing in Vehicular Ad Hoc Networks write by Faisal Ahmad Khan. This book was released on 2013. Safety-message Routing in Vehicular Ad Hoc Networks available in PDF, EPUB and Kindle. The safety-message dissemination problem for vehicular ad hoc networks (VANETs) was investigated. Four novel techniques were contributed for the efficient and reliable routing of safety messages in the vehicular ad hoc networks. The instant-broadcast technique was proposed to improve the end-to-end dissemination delay. The lane-based sectoring mechanism was presented for the collision mitigation in the dense-urban traffic scenario. The negative acknowledgment with smart neighborhood (NSN) technique was proposed to ensure the reliability of reception through recovering the packet loss caused by interference. Finally, the negative acknowledgment with smart neighborhood - hole recovery (NSN-H) technique was presented to provide guaranteed reception of the safety message at each individual node in the VANET. The investigation of the safety message routing in VANET conducted in this research also revealed the significance of hitherto-neglected factors that influence the vehicular network. Significance of the small payload size of the VANET safety message, the effect of road width on the multi-hop relay, and the attenuation caused by vehicles in the propagation path were among the important revealed factors.
Adaptive Mechanisms to Improve Message Dissemination in Vehicular Networks
Adaptive Mechanisms to Improve Message Dissemination in Vehicular Networks - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Adaptive Mechanisms to Improve Message Dissemination in Vehicular Networks write by Julio A. Sangüesa Escorihuela. This book was released on 2014-11-14. Adaptive Mechanisms to Improve Message Dissemination in Vehicular Networks available in PDF, EPUB and Kindle. Doctoral Thesis / Dissertation from the year 2014 in the subject Engineering - Computer Engineering, grade: Sobresaliente Cum Laude, , language: English, abstract: In the past, people were focused on how to build efficient highways and roads. Over time, focus shifted to mechanical and automotive engineering, in the pursuit of building faster cars to surmount greater distances. Later on, electronics technology impacted the construction of cars, embedding them with sensors, advanced electronics, and communication devices, making cars more intelligent, efficient, and safe to drive on. The applications and advantages of using Vehicular Networks (VNs) for enhancing road safety and driving efficiency are diverse, which explains why research in this area has recently emerged. In this Thesis, we focus on Vehicular Adhoc Networks (VANETs), which are a particular subclass of Vehicular Networks, that involves a set of equipped vehicles communicating with each other via wireless antennas, without requiring the use of any infrastructure. In order to enhance the warning message dissemination process, usually necessary in VANET safety applications, we propose an adaptive broadcast dissemination scheme that automatically chooses the optimal broadcast depending on the complexity of the map and the instantaneous vehicle density in the area. Its main goal is to maximize the message delivery effectiveness, while generating a reduced number of messages, and thus, avoiding or mitigating broadcast storms. Current research on VANETs usually focuses on analyzing scenarios representing common situations with average densities. However, situations with very low or very high vehicle densities are often ignored, whereas they are very common in real vehicular environments. The aim of broadcast dissemination schemes is to maximize message delivery effectiveness, something difficult to achieve in adverse density scenarios. To address this issue, in this Thesis, we propose the Junction Store and Forward (JSF) and the Neighbor Store and Forward (NSF) dissemina- tion schemes, specially designed to be used under low density conditions, as well as the Nearest Junction Located (NJL) scheme, specially developed for high density conditions. Finally, we present a classification which includes the most relevant broadcast dissemination schemes specially designed for VANETs, highlighting their features, and studying their performance under the same simulation conditions, thus offering researchers a fair comparison. We consider that this evaluation can shed some light into the advantages and drawbacks of each solution.
Emergency Message Dissemination in VANET
Emergency Message Dissemination in VANET - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Emergency Message Dissemination in VANET write by C Patel Hitesh. This book was released on 2015-06-23. Emergency Message Dissemination in VANET available in PDF, EPUB and Kindle. Vehicular ad hoc networks (VANETs) are more and more popular now a day.Vehicle-to-Vehicle Communication are most used today.Simple type of communication are not useful in Emergency situation when Vehicle want to Disseminate emergency Message to following Vehicle.what happen if message not reach in time? Broadcasting storm problem are dangerous in this kind of situation because message cant not reach in time and moreover there is a threat of message collision. How to deal with Broadcast Storm Problem? In This work we deal with this issue.we develop EMD Algorithm to deal with this issue.
