Performance evaluation of a hybrid vehicle and sensor network to prevent traffic accidents

In recent years, wireless networks have become a widespread communication technology as well as a research challenge. Many contributions have been made on ad hoc networks, such as wireless sensor networks (WSNs) and vehicular ad hoc networks (VANETs). Recently, the number of cars on our streets, roads, and highways has been increasing, giving rise to a great interest in vehicular communication technologies. This paper presents an hybrid sensor and vehicular network (HSVN) platform, as well as the description and evaluation of a communication protocol between VANETs and WSNs using a network simulator for its evaluation

Location based services in wireless ad hoc networks

In this dissertation, we investigate location based services in wireless ad hoc networks from four different aspects - i) location privacy in wireless sensor networks (privacy), ii) end-to-end secure communication in randomly deployed wireless sensor networks (security), iii) quality versus latency trade-off in content retrieval under ad hoc node mobility (performance) and iv) location clustering based Sybil attack detection in vehicular ad hoc networks (trust). The first contribution of this dissertation is in addressing location privacy in wireless sensor networks. We propose a non-cooperative sensor localization algorithm showing how an external entity can stealthily invade into the location privacy of sensors in a network. We then design a location privacy preserving tracking algorithm for defending against such adversarial localization attacks. Next we investigate secure end-to-end communication in randomly deployed wireless sensor networks. Here, due to lack of control on sensors\u27 locations post deployment, pre-fixing pairwise keys between sensors is not feasible especially under larger scale random deployments. Towards this premise, we propose differentiated key pre-distribution for secure end-to-end secure communication, and show how it improves existing routing algorithms. Our next contribution is in addressing quality versus latency trade-off in content retrieval under ad hoc node mobility. We propose a two-tiered architecture for efficient content retrieval in such environment. Finally we investigate Sybil attack detection in vehicular ad hoc networks. A Sybil attacker can create and use multiple counterfeit identities risking trust of a vehicular ad hoc network, and then easily escape the location of the attack avoiding detection. We propose a location based clustering of nodes leveraging vehicle platoon dispersion for detection of Sybil attacks in vehicular ad hoc networks --Abstract, page iii

A survey on probabilistic broadcast schemes for wireless ad hoc networks

Broadcast or flooding is a dissemination technique of paramount importance in wireless ad hoc networks. The broadcast scheme is widely used within routing protocols by a wide range of wireless ad hoc networks such as mobile ad hoc networks, vehicular ad hoc networks, and wireless sensor networks, and used to spread emergency messages in critical scenarios after a disaster scenario and/or an accidents. As the type broadcast scheme used plays an important role in the performance of the network, it has to be selected carefully. Though several types of broadcast schemes have been proposed, probabilistic broadcast schemes have been demonstrated to be suitable schemes for wireless ad hoc networks due to a range of benefits offered by them such as low overhead, balanced energy consumption, and robustness against failures and mobility of nodes. In the last decade, many probabilistic broadcast schemes have been proposed by researchers. In addition to reviewing the main features of the probabilistic schemes found in the literature, we also present a classification of the probabilistic schemes, an exhaustive review of the evaluation methodology including their performance metrics, types of network simulators, their comparisons, and present some examples of real implementations, in this paper

Novel Medium Access Control (MAC) Protocols for Wireless Sensor and Ad Hoc Networks (WSANs) and Vehicular Ad Hoc Networks (VANETs)

Efficient medium access control (MAC) is a key part of any wireless network communication architecture. MAC protocols are needed for nodes to access the shared wireless medium efficiently. Providing high throughput is one of the primary goals of the MAC protocols designed for wireless networks. MAC protocols for Wireless Sensor and Ad hoc networks (WSANs) must also conserve energy as sensor nodes have limited battery power. On the other hand, MAC protocols for Vehicular Ad hoc networks (VANETs) must also adapt to the highly dynamic nature of the network. As communication link failure is very common in VANETs because of the fast movement of vehicles so quick reservation of packet transmission slots by vehicles is important. In this thesis we propose two new distributed MAC algorithms. One is for WSANs and the other one is for VANETs. We demonstrate using simulations that our algorithms outperform the state-of-the-art algorithms

NaMANET – Nagy kiterjedésű mobil ad hoc hálózatok vizsgálata = NaMANET - Investigation of Large-Scale Mobile Ad Hoc Networks

A NaMANET projekt keretében elsősorban a nagy kiterjedésű mobil ad hoc hálózatok, valamint a vezeték nélküli közösségi hálózatok témájával foglalkoztunk. A mobil ad hoc hálózatok közvetlen adatátvitelt biztosító kommunikációs megoldásokra épülő lokális hálózatok, míg a vezeték nélküli közösségi hálózatok ideális körülményeket nyújthatnak ad hoc alkalmazások implementálására és bevezetésére mintegy összekötő gerinchálózatot biztosítva a mobil ad hoc hálózati szigetek számára. Kutatásaink során modelleztük és szimulációk segítségével vizsgáltuk az alkalmazásterjedést nagy kiterjedésű ad hoc hálózatokban. Összehasonlítottuk különböző szolgáltatásmenedzsment architektúrák teljesítőképességét. Megvizsgáltuk különböző információterjesztési stratégiák hatékonyságát járművek alkotta ad hoc hálózatokban, valamint megvizsgáltunk különböző klaszterezési eljárásokat biztonság és megbízhatóság szempontjából szenzor hálózatokban. Foglalkoztunk okostelefonok ad hoc hálózatokban való használatával. Terveztünk és implementáltunk egy szolgáltatástámogatási keretrendszert demo alkalmazásokkal, valamint megvizsgáltuk az ad hoc hálózatok alkalmazhatóságának kérdéskörét beltéri navigációs rendszer esetén. Foglalkoztunk vezeték nélküli közösségi hálózatok tervezési, kiépítési, üzemeltetési kérdéseivel, továbbá kidolgoztunk egy link állapotváltozást előrejelző eljárást vezeték nélküli hálózatokra. Eredményeinket számos nemzetközi konferenciacikk, folyóiratcikk és könyvfejezet formájában publikáltuk. | In the NaMANET project, we mainly focused on the investigation of large-scale mobile ad hoc networks, and the field of wireless community networks. In mobile ad hoc networks, the mobile nodes close to each other can communicate directly with their neighbors, since wireless community networks can provide ideal conditions as a backbone of the ad hoc network islands for implementing and deploying ad hoc applications. In our research, we modeled and via simulations investigated application spreading in large-scale ad hoc networks. We compared the performance of different service management architectures. We investigated the efficiency of different message spreading strategies in vehicular ad hoc networks, moreover surveyed and analysed clustering algorithms and protocols used in sensor networks from the viewpoint of security and reliability. We also dealt with using smartphones in ad hoc networks. We developed and implemented a service provisioning framework for ad hoc networks together with some demo applications, and investigated the usability of ad hoc networks in indoor navigation. Furthermore, we dealt with the area of developing, deploying and maintaining wireless community networks, and developed a link state prediction algorithm for wireless networks. We published our results in several international conference papers, journal papers and book chapters

Vehicular Ad hoc Network

A Vehicular Ad-Hoc Network (VANET) is a mobile Ad-Hoc Network that provides connectivity moving device to fixed equipments. Such type of device is equipped with vehicle provides safety for the passengers. In the recent research areas of traffic management there observed the wide scope of design of new methodology of extension of wireless sensor networks and ad-hoc network principal for development of VANET technology. In this paper provides the wide research view of the VANET and MANET concept for the researchers to contribute the better optimization technique for the development of effective and fast atomization technique for the large size of data exchange in this complex networks

Performance evaluation of a hybrid sensor and vehicular network to improve road safety

In the last years, wireless networks have become a widely spread type of communication technology and also a challenging scientific area for new fields of research. Many contributions in ad hoc networks, such as WSNs (Wireless Sensor Networks) and VANETs (Vehicular Ad Hoc Networks), have been proposed. Nowadays, the huge amount of cars in transit has raised a big interest in vehicular communication technologies. A new type of network has been developed, named HSVN (Hybrid Sensor and Vehicular Network) in which WSNs and VANETs cooperate with the aim of improving road safety. Recent projects, such as CVIS [1] and COMeSafety [2], are focused on improving the road driving. This type of approaches will warn the driver and the co-pilot of any event occurred in the road ahead, such as traffic jam, accidents, bad weather, etc. This way, the number of traffic accidents may decrease and many lives might be saved. Besides, a better selection of non-congested roads will help to reduce pollution. In addition, other attractive services, such as downloading of multimedia services or Internet browsing, would be easily available through infrastructure along the roadside. Transportation in motorways will be easier, safer and more comfortable for passengers. In this paper a HSVN platform is presented, also a communications protocol between VANETs and WSNs is described and evaluated using the NCTUns [3] simulator.Postprint (published version