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Mobility Models for Vehicular Ad Hoc Networks: A Survey and Taxonomy
, 2006
"... Vehicular Ad-hoc Networks (VANETs) have been recently attracting an increasing attention from both research and industry communities. One of the challenges posed by the study of VANETs is the definition of a generic mobility model providing an accurate, realistic vehicular mobility description at bo ..."
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Cited by 56 (1 self)
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Vehicular Ad-hoc Networks (VANETs) have been recently attracting an increasing attention from both research and industry communities. One of the challenges posed by the study of VANETs is the definition of a generic mobility model providing an accurate, realistic vehicular mobility description at both macroscopic and microscopic levels. Today, most mobility models for vehicular studies only consider a limited macro-mobility, involving restricted vehicles movements, while little or no attention is paid to micro-mobility and its interaction with the macro-mobility counterpart. On the other hand, the research community cannot have access to realistic traffic generator which have not been designed to collaborate with network simulators. In this paper, we first introduce a classification of existing methods for the generation of vehicular mobility models, then we describe the various approaches used by the community for realistic VANET simulations. Finally, we provide an overview and comparison of a large range of mobility models proposed for
Vehicular Ad Hoc Networks (VANETS): Status, Results, and Challenges
"... Recent advances in hardware, software, and communication technologies are enabling the design and implementation of a whole range of different types of networks that are being deployed in various environments. One such network that has received a lot of interest in the last couple of years is the Ve ..."
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Cited by 27 (1 self)
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Recent advances in hardware, software, and communication technologies are enabling the design and implementation of a whole range of different types of networks that are being deployed in various environments. One such network that has received a lot of interest in the last couple of years is the Vehicular Ad-Hoc Network (VANET). VANET has become an active area of research, standardization, and development because it has tremendous potential to improve vehicle and road safety, traffic efficiency, and convenience as well as comfort to both drivers and passengers. Recent research efforts have placed a strong emphasis on novel VANET design architectures and implementations. A lot of VANET research work have focused on specific areas including routing, broadcasting, Quality of Service (QoS), and security. We survey some of the recent research results in these areas. We present a review of wireless access standards for VANETs, and describe some of the recent VANET trials and deployments in the US, Japan, and the European Union. In addition, we also briefly present some of the simulators currently available to VANET researchers for VANET simulations and we assess their benefits and limitations. Finally, we outline some of the VANET research challenges that still need to be addressed to enable the ubiquitous deployment and widespead adoption of scalable, reliable, robust, and secure VANET architectures, protocols, technologies, and services. 1.
To Cache or Not to Cache
- IEEE INFOCOM
, 2009
"... Abstract—We address cooperative caching in mobile ad hoc networks where information is exchanged in a peer-to-peer fashion among the network nodes. Our objective is to devise a fully-distributed caching strategy whereby nodes, independently of each other, decide whether to cache or not some content, ..."
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Cited by 20 (3 self)
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Abstract—We address cooperative caching in mobile ad hoc networks where information is exchanged in a peer-to-peer fashion among the network nodes. Our objective is to devise a fully-distributed caching strategy whereby nodes, independently of each other, decide whether to cache or not some content, and for how long. Each node takes this decision according to its perception of what nearby users may be storing in their caches and with the aim to differentiate its own cache content from the others’. We aptly named such algorithm “Hamlet”. The result is the creation of a content diversity within the nodes neighborhood, so that a requesting user likely finds the desired information nearby. We simulate our caching algorithm in an urban scenario, featuring vehicular mobility, as well as in a mall scenario with pedestrians carrying mobile devices. Comparison with other caching schemes under different forwarding strategies confirms that Hamlet succeeds in creating the desired content diversity thus leading to a resource-efficient information access. I.
Vehicular Mobility Simulation with VanetMobiSim,” Transactions of The Society for Modeling and Simulation
"... During the last few years, continuous progresses in wireless communications have opened new research fields in computer networking, aimed at extending data networks connectivity to environ-ments where wired solutions are impracticable. Among these, vehicular communication is attract-ing growing atte ..."
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Cited by 14 (6 self)
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During the last few years, continuous progresses in wireless communications have opened new research fields in computer networking, aimed at extending data networks connectivity to environ-ments where wired solutions are impracticable. Among these, vehicular communication is attract-ing growing attention from both academia and industry, owing to the amount and importance of the related applications, ranging from road safety to traffic control and up to mobile entertainment. Vehicular Ad-hoc Networks (VANETs) are self-organized networks built up from moving vehicles, and are part of the broader class of Mobile Ad-hoc Networks (MANETs). Owing to their peculiar characteristics, VANETs require the definition of specific networking techniques, whose feasibility and performance are usually tested by means of simulation. One of the main challenges posed by VANETs simulations is the faithful characterization of vehicular mobility at both the macroscopic and microscopic levels, leading to realistic non-uniform distributions of cars and velocity, and unique connectivity dynamics. However, freely distributed tools which are commonly used for academic studies only consider limited vehicular mobility issues, while they pay little or no attention to vehic-ular traffic generation and its interaction with its motion constraints counterpart. Such a simplistic approach can easily raise doubts on the confidence of derived VANETs simulation results. In this
Large-scale Urban Vehicular Mobility for Networking Research
- IEEE VNC
, 2011
"... Abstract—Simulation is the tool of choice for the large-scale performance evaluation of upcoming telecommunication networking paradigms that involve users aboard vehicles, such as next-generation cellular networks for vehicular access, pure vehicular ad hoc networks, and opportunistic disruption-tol ..."
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Cited by 12 (5 self)
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Abstract—Simulation is the tool of choice for the large-scale performance evaluation of upcoming telecommunication networking paradigms that involve users aboard vehicles, such as next-generation cellular networks for vehicular access, pure vehicular ad hoc networks, and opportunistic disruption-tolerant networks. The single most distinguishing feature of vehicular networks simulation lies in the mobility of users, which is the result of the interaction of complex macroscopic and microscopic dynamics. Notwithstanding the improvements that vehicular mo-bility modeling has undergone during the past few years, no car traffic trace is available today that captures both macroscopic and microscopic behaviors of drivers over a large urban region, and does so with the level of detail required for networking research. In this paper, we present a realistic synthetic dataset of the car traffic over a typical 24 hours in a 400-km2 region around the city of Köln, in Germany. We outline how our mobility description improves today’s existing traces and show the potential impact that a comprehensive representation of vehicular mobility can have one the evaluation of networking technologies. I.
Improving Propagation Modeling in Urban Environments for Vehicular Ad Hoc Networks
"... Abstract — Developing applications, especially real-time ones, for wireless vehicular ad hoc networks (VANETs) requires a reasonable assurance of the likely performance of the network, at the least in terms of packet loss ratios and end-to-end delay. Because wireless propagation strongly influences ..."
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Cited by 10 (0 self)
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Abstract — Developing applications, especially real-time ones, for wireless vehicular ad hoc networks (VANETs) requires a reasonable assurance of the likely performance of the network, at the least in terms of packet loss ratios and end-to-end delay. Because wireless propagation strongly influences performance, especially in an urban environment, this paper improves on simpler propagation models for simulations by augmenting ray-tracing derived models of propagation. In the non-line-of-sight component: the propagation distance is more closely calculated according to the reflection distance; the effect of roadside obstacles is included; and for modeling of fast fading a phase factor is introduced, all without necessarily overly increasing computational load. In the line-of-sight component, as well as roadside obstacle modeling: single and double reflections from roadside buildings are added to the standard two-ray ground-propagation model; the distribution of vehicles within a street segment is used to model the ground reflection ray more closely; and the reflection coefficient is also adjusted accordingly to account for reflections from vehicles. The results have been compared with widely-used measurement studies of city streets in the literature, which have confirmed the overall advantage of the improvements, especially in the case of the non-line-of-sight component. A simulation case study shows that in general optimistic performance predictions of packet loss occur with the two-ray ground propagation model when indiscriminately applied. The paper, therefore, represents a way forward for VANET wireless channel modeling in simulations. Index Terms—simulation, urban environment, vehicle-to-vehicle communication, wireless propagation G I.
Privacy-Preserving Reconstruction of Multidimensional Data Maps in Vehicular Participatory Sensing
"... Abstract. The proliferation of sensors in devices of frequent use, such as mobile phones, offers unprecedented opportunities for forming selfselected communities around shared sensory data pools that enable community specific applications of mutual interest. Such applications have recently been term ..."
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Cited by 10 (5 self)
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Abstract. The proliferation of sensors in devices of frequent use, such as mobile phones, offers unprecedented opportunities for forming selfselected communities around shared sensory data pools that enable community specific applications of mutual interest. Such applications have recently been termed participatory sensing. An important category of participatory sensing applications is one that construct maps of different phenomena (e.g., traffic speed, pollution) using vehicular participatory sensing. An example is sharing data from GPS-enabled cell-phones to map traffic or noise patterns. Concerns with data privacy are a key impediment to the proliferation of such applications. This paper presents theoretical foundations, a system implementation, and an experimental evaluation of a perturbation-based mechanism for ensuring privacy of location-tagged participatory sensing data while allowing correct reconstruction of community statistics of interest (computed from shared perturbed data). The system is applied to construct accurate traffic speed maps in a small campus town from shared GPS data of participating vehicles, where the individual vehicles are allowed to “lie ” about their actual location and speed at all times. An extensive evaluation demonstrates the efficacy of the approach in concealing multi-dimensional, correlated, time-series data while allowing for accurate reconstruction of spatial statistics. 1
An Overlay Architecture for Vehicular Networks
"... We propose and discuss an overlay architecture relying on a mobile ad hoc network, called Arigatoni on wheels (Ariwheels for short). More specifically, Ariwheels is a virtual network organization that is designed for a vehicular network underlay environment. It provides efficient and transparent se ..."
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Cited by 8 (3 self)
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We propose and discuss an overlay architecture relying on a mobile ad hoc network, called Arigatoni on wheels (Ariwheels for short). More specifically, Ariwheels is a virtual network organization that is designed for a vehicular network underlay environment. It provides efficient and transparent service advertising and retrieves services carried by on-board and roadside nodes. The paper outlines application scenarios for Ariwheels and evaluates them through simulation in a realistic vehicular environment.
Communication Requirements for Crash Avoidance
- in Proc. IEEE VANET ’10
, 2010
"... Safety applications are a driving force behind VANET deployment. Automobile manufacturers, government organizations, and consortia of the two have been investigating using VANETs for safety applications. Though VANETs are in large part designed for safety applications, researchers do not yet know th ..."
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Cited by 8 (1 self)
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Safety applications are a driving force behind VANET deployment. Automobile manufacturers, government organizations, and consortia of the two have been investigating using VANETs for safety applications. Though VANETs are in large part designed for safety applications, researchers do not yet know the communication requirements of VANET safety messages. As a result, protocol designers have relied on generic network success metrics, such as packet delivery ratio, to evaluate their protocols. However, a more useful metric is the ability of currently proposed VANET schemes (e.g., for authentication, power control, etc.) to allow vehicles to receive safety messages and warn their drivers sufficiently in advance of an accident so that the driver can avoid the accident. Besides the basic safety message service, researchers have proposed other VANET mechanisms and services including mix zones [2,
Trust No One: A Decentralized Matching Service for Privacy in Location Based Services
, 2010
"... We propose a new approach to ensure privacy in location based services, without requiring any support from a“trusted” entity. We observe that users of location based services are sensitive about their i) location coordinates and ii) their interests and social relationships, as captured in their quer ..."
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Cited by 7 (0 self)
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We propose a new approach to ensure privacy in location based services, without requiring any support from a“trusted” entity. We observe that users of location based services are sensitive about their i) location coordinates and ii) their interests and social relationships, as captured in their queries. We also observe there are entities that naturally have access to at least one of these pieces of information. The user and/or their mobile operator has access to their current location, and the LBS provider needs to know of the interests (in businesses, services and acquaintances) of a user. In this paper we consider whether it is possible for these entities to exchange information such that a user’s queries to the LBS can be answered without i) any one entity coming to know of all sensitive information ii) a loss in the quality of service of the query, or an inordinate load on the user. Specifically, we outline the design of a decentralized matching service that takes encoded information from both the participating entities, and creates triggers when a user, and their objects of interest are in the vicinity of each other. Given that each component of the matching service has access to only a limited amount of encoded information, we argue that it will be impossible to recreate any sensitive user-specific information.
