Rodolfo Ipolito Meneguette

A seamless flow mobility management architecture for vehicular communication networks

Vehicular ad-hoc networks (VANETs) are self-organizing, self-healing networks which provide wireless communication among vehicular and roadside devices. Applications in such networks can take advantage of the use of simultaneous connections, thereby maximizing the throughput and lowering latency. In order to take advantage of all radio interfaces of the vehicle and to provide good quality of service for vehicular applications, we developed a seamless flow mobility management architecture based on vehicular network application classes with network-based mobility management. Our goal is to minimize the time of flow connection exchange in order to comply with the minimum requirements of vehicular application classes, as well as to maximize their throughput. Network simulator (NS-3) simulations were performed to analyse the behaviour of our architecture by comparing it with other three scenarios. As a result of this work, we observed that the proposed architecture presented a low handover time, with lower packet loss and lower delay.

A self-adaptive data dissemination solution for intelligent transportation systems

Intelligent Transportation Systems (ITS) rely on Inter-Vehicle Communication (IVC) to streamline the operation of vehicles by managing vehicle traffic, assisting drivers with safety and other information, along with the provisioning of convenience applications for passengers. For that, many applications and services use broadcast to perform the transmission of their data to intended recipients. However, due to the wireless medium and the characteristics inherent to vehicular environments, broadcasting becomes a challenging task. For instance, uncoordinated broadcasts may lead to severe packet collisions, thus resulting in network congestion. Such problem is well known as the broadcast storm problem. Moreover, the broadcasting mechanism must handle network disconnections, otherwise, the data delivery capability may be hampered. Although there are many studies that deal with these problems separately, very few consider a solution for both problems. Furthermore, those that handle both problems do not consider different scenarios, i.e., they only focus on urban or highway scenarios. Therefore, to deal with both problems and different scenarios, we propose a preemptive algorithm that automatically adjusts the data transmission process (PREDAT) to reduce the total number of collisions and maximize the data delivery capability across network disconnections. Simulation results show that our proposed solution induces short delays and a low overhead. Moreover, it provides good efficiency with respect to the coverage of the event and the distance to which the information is propagated.

Decreasing greenhouse emissions through an intelligent traffic information system based on inter-vehicle communication

Traffic congestion is an urban mobility problem, which generates stress to drivers and economic losses. In 2012, greenhouse gas emissions from transportation accounted for about 28% of total U.S. greenhouse gas emissions. Intelligent transportation systems can assist in the identification and reduction of vehicular traffic congestion. In this context, this work proposes an intelligent traffic information system based on inter-vehicle communication to avoid vehicle traffic congestion. The main goal of the proposed solution is to decrease CO2 emissions, the average trip time and fuel consumption by avoiding congested roads. Simulation results show that our proposed solution can reduce the average trip time, and the overall CO2 emission and fuel consumption. In particular, the trip time was decreased approximately 86%, the fuel consumption 40% and the CO2 emission 55%. This shows the potential of the proposed solution.

Scorpion: A Solution Using Cooperative Rerouting to Prevent Congestion and Improve Traffic Condition

Most large cities suffer with congestion problem, one of the main causes of congestion is the sudden increase of vehicle traffic during peak hours, mainly in areas with bottlenecks. Current solutions in the literature are based on perceiving road traffic conditions and re-routing vehicles to avoid the congested area. However, they do not consider the impact of thesechanges on near future traffic patterns. Hence, these approachesare unable to provide a long-term solution to the congestion problem, since when suggesting alternative routes, they create new bottlenecks at roads closer to the congested one, thus just transferring the problem from one point to another one. With this issue in mind, we propose an intelligent traffic cooperative routing application called SCORPION, which improves the overall spatial utilization of a road network and also reduces the average vehicletravel costs by avoiding vehicles from getting stuck in traffic. Simulation results show that our proposal is able to forecasting congestion and re-route vehicles properly, performing a load balance of vehicular traffic.

Autonomic data dissemination in highway Vehicular Ad Hoc Networks with diverse traffic conditions

A Vehicular Ad Hoc Network (VANET) is a subclass of Mobile Ad Hoc Networks, which provides wireless communication among vehicles as well as between vehicles and roadside units. Providing safety, traffic efficiency and user comfort for drivers and passengers are promising goals of these networks. To reach these goals many envisaged applications for VANETs will rely on data dissemination, turning this task into an essential service. However, due to some inherent characteristics of VANETs, such as intermittent connectivity, highly dynamic topology, and diverse network densities, data dissemination is a challenging activity in this kind of network. Although data dissemination has been extensively studied in the literature, existing solutions do not effectively address the broadcast storm and network partition problems when considered together. To deal with both problems, we propose a network partition-aware geographical data dissemination protocol, which eliminates the broadcast storm and maximizes the data dissemination capability across network partitions with short delays and low overhead. The proposed algorithm is able to autonomically adjust message transmissions in the network. Simulation results show that our proposed approach provides good efficiency with respect to the coverage of event processing, delay and overhead.

VANets: An Exploratory Evaluation in Vehicular Ad Hoc Network for Urban Environment

Vehicular Ad hoc Network (VANET) is a promising communication technology suitable for vehicular mobile networks. Represent networks of singular features, wherein the data dissemination is fundamental. The literature is plentiful in protocols, usually specific to address individual issues in well-defined scenarios. This work efforts are concentrated, mainly, to examine operating settings in protocols like AID, DBRS, and ADDHV for disseminating messages. A benchmarking explores strategies that address challenges such as network partitioning and the broadcast storm problem, which undertake the dissemination. The results of a set of metrics obtained in different vehicular traffic schemes complete the discussion held. Considerations for answers in coverage, delay, rate of delivery, broadcast, and packet loss support this initiative and motivate the development of an adaptive solution to fluctuations in carrier density.

An Architecture for Hierarchical Software-Defined Vehicular Networks

With the recent advances in the telecommunications and auto industries, we have witnessed growing interest in ITS, of which VANETs are an essential component. SDN can bring advantages to ITS through its ability to provide flexibility and programmability to networks through a logically centralized controller entity that has a comprehensive view of the network. However, as the SDN paradigm initially had fixed networks in mind, adapting it to work on VANETs requires some changes to address particular characteristics of this kind of scenario, such as the high mobility of its nodes. There has been initial work on bringing SDN concepts to vehicular networks to expand its abilities to provide applications and services through the increased flexibility, but most of these studies do not directly tackle the issue of loss of connectivity with said controller entity. In this article, we propose a hierarchical SDN-based vehicular architecture that aims to have improved performance in the situation of loss of connection with the central SDN controller. Simulation results show that our proposal outperforms traditional routing protocols in the scenario where there is no coordination from the central SDN controller.

A Health Smart Home System to Report Incidents for Disabled People

Health Smart Home (HSH) provides health care services for people with special needs and wish to be independent and remain in their own home. The residence is equipped with automatic devices and a range of sensors to ensure the safety of the patients at home and the supervision of their health status. These Health Smart Homes have been increasingly studied not only by the academic community but also by industry on account of the great potential it has, especially in applications that can help people with some type of physical disability such as visual or hearing impairment. We implemented a system witch monitors rooms and issues a warning whenever it detects a potential hazard. Our proposal relies on low-cost cutting-edge technology.

GARUDA: A New Geographical Accident Aware Solution to Reduce Urban Congestion

In cities where the number of vehicles continuously increases faster than the available infrastructure, traffic congestion is a difficult issue to deal with. This problem becomes even worse in case of accidents that affects many aspects of the modern society, including economic development and CO2 emission. Several solutions for Intelligent Transportation Systems have been proposed to identify congestions and re-route the vehicles afterwards. This work introduces GARUDA, a fully distributed and pro-active intelligent traffic information system, which avoid congestions, calculates new routes, and notifies drivers to follow new paths proactively. Simulation results show the effectiveness of GARUDA. When compared to original vehicular mobility trace, GARUDA reduces the average trip time in approximately 53%, the overall CO 2 emission in 26% and the fuel consumption in 28%.

SMART: An Efficient Resource Search and Management Scheme for Vehicular Cloud-Connected System

A Vehicular Cloud generally focuses on several aspects, which include providing a set of computational services at low cost to vehicle drivers; minimizing traffic congestion, accidents, travel time, and environmental pollution; and ensuring the use of low energy and real-time services of software, platforms, and infrastructure with QoS to drivers. The largest challenge in vehicular mobile Clouds consists of creating a mechanism for management and search resources that does not depend on roadside infrastructure, which consequently requires the spontaneous and dynamic creation of a Cloud through the resources shared by vehicles. Therefore, the system must enable collaboration and co-operation between vehicles so that they may establish connections to provide resources. To address this challenge, we propose a peer-to-peer protocol to assist in the discovery and management of resources in a vehicular mobile Cloud without depending on the support of a roadside infrastructure so that vehicles are expected to organize themselves and establish collaborations to manage and share their resources. Simulation results show that the proposed approach introduces a short search time of approximately 0.5 (ms) to seek resources in one hop and approximately 0.9 (ms) to seek more of a hop in resources. Furthermore, the proposed protocol enables a high availability of resources, about 87%.