Video upload from public transport vehicles using multihomed systems

Abstract: We consider a surveillance system for public transport vehicles, which is based on the collection of on-board videos, and the upload via mobile network to a central security system of video segments corresponding to those cameras and time intervals involved in an accident. We assume that vehicles are connected to several wireless interfaces, provided by different Mobile Network Operators (MNOs), each charging a different cost. Both the cost and the upload rate for each network interface change over time, according to the network load and the position of the vehicle. When a video must be uploaded to the central security, the system has to complete the upload within a deadline, deciding i) which interface(s) to use, ii) when to upload from that interface(s) and iii) at which rate to upload. The goal is to minimize the total cost of the upload, which we assume to be proportional to the data volume being transmitted and to the cost of using a given interface. We formalize the optimization problem and discuss greedy heuristics to solve it. Then, we discuss scientific and technical challenges to solve the system

Experimentation and Characterization of Mobile Broadband Networks

The Internet has brought substantial changes to our life as the main tool to access a large variety of services and applications. Internet distributed nature and technological improvements lead to new challenges for researchers, service providers, and network administrators. Internet traffic measurement and analysis is one of the most trivial and powerful tools to study such a complex environment from different aspects. Mobile BroadBand (MBB) networks have become one of the main means to access the Internet. MBB networks are evolving at a rapid pace with technology enhancements that promise drastic improvements in capacity, connectivity, and coverage, i.e., better performance in general. Open experimentation with operational MBB networks in the wild is currently a fundamental requirement of the research community in its endeavor to address the need for innovative solutions for mobile communications. There is a strong need for objective data relating to stability and performance of MBB (e.g., 2G, 3G, 4G, and soon-to-come 5G) networks and for tools that rigorously and scientifically assess their performance. Thus, measuring end user performance in such an environment is a challenge that calls for large-scale measurements and profound analysis of the collected data. The intertwining of technologies, protocols, and setups makes it even more complicated to design scientifically sound and robust measurement campaigns. In such a complex scenario, the randomness of the wireless access channel coupled with the often unknown operator configurations makes this scenario even more challenging. In this thesis, we introduce the MONROE measurement platform: an open access and flexible hardware-based platform for measurements on operational MBB networks. The MONROE platform enables accurate, realistic, and meaningful assessment of the performance and reliability of MBB networks. We detail the challenges we overcame while building and testing the MONROE testbed and argue our design and implementation choices accordingly. Measurements are designed to stress performance of MBB networks at different network layers by proposing scalable experiments and methodologies. We study: (i) Network layer performance, characterizing and possibly estimating the download speed offered by commercial MBB networks; (ii) End users’ Quality of Experience (QoE), specifically targeting the web performance of HTTP1.1/TLS and HTTP2 on various popular web sites; (iii) Implication of roaming in Europe, understanding the roaming ecosystem in Europe after the "Roam like Home" initiative; and (iv) A novel adaptive scheduler family with deadline is proposed for multihomed devices that only require a very coarse knowledge of the wireless bandwidth. Our results comprise different contributions in the scope of each research topic. To put it in a nutshell, we pinpoint the impact of different network configurations that further complicate the picture and hopefully contribute to the debate about performance assessment in MBB networks. The MBB users web performance shows that HTTP1.1/TLS is very similar to HTTP2 in our large-scale measurements. Furthermore, we observe that roaming is well supported for the monitored operators and the operators using the same approach for routing roaming traffic. The proposed adaptive schedulers for content upload in multihomed devices are evaluated in both numerical simulations and real mobile nodes. Simulation results show that the adaptive solutions can effectively leverage the fundamental tradeoff between the upload cost and completion time, despite unpredictable variations in available bandwidth of wireless interfaces. Experiments in the real mobile nodes provided by the MONROE platform confirm the findings

Adaptive schedulers for deadline-constrained content upload from mobile multihomed vehicles

We consider the practical problem of video surveillance in public transport systems, where security videos are stored onboard, and a central operator occasionally needs to access portions of the recordings. When this happens, the selected video must be uploaded within a deadline, possibly using multiple parallel wireless interfaces. Interfaces have different associated costs, related to tariffs charged by Mobile Network Operators (MNOs), energy consumption, data quotas, system load. Our goal is to choose which interfaces to use, and when, so as to minimize the cost of the upload while meeting the deadline, despite the unknown short-term variations in throughput. To achieve this goal, we first collect real traces of mobile uploads from vehicles for different MNOs. Examination of these traces confirms the unpredictability of the short-term throughput of wireless connections, and motivates the adoption of adaptive schedulers with limited a-priori knowledge of the system status. To effectively solve our problem, we devised a family of adaptive algorithms, that we thoroughly evaluated using a trace-driven approach. Results show that our adaptive approach can effectively leverage the fundamental tradeoff between the total cost and the delivery time of content upload, despite unknown short-term variations in throughput

Capacity analysis in different systems exploiting mobility of VANETs

Improving road safety and traffic efficiency has been a long-term endeavor for not only government but also automobile industry and academia. After the U.S. Federal Communication Commission (FCC) allocated a 75 MHz spectrum at 5.9 GHz for vehicular communications, the vehicular ad hoc network (VANET), as an instantiation of the mobile ad hoc network (MANET) with much higher node mobility, opens a new door to combat the road fatalities. In VANETs, a variety of applications ranging from safety related (e.g. emergency report, collision warning) to non-safety-related (e.g. infotainment and entertainment) can be enabled by vehicle-to-vehicle (V2V) and vehicle-to-roadside (V2R) communications. However, the flourish of VANET still hinges fully understanding and managing the challenges that the public concerns, for example, capacity and connectivity issues due to the high mobility of vehicles. In this thesis, we investigate how vehicle mobility can impact the performance in three important VANET-involved systems, i.e., pure VANET, VANET-enhanced intelligent transportation systems (ITS), and fast electric vehicle (EV) charging systems. First, in pure VANET, our work shows that the network data-traffic can be balanced and the network throughput can be improved with the help of the vehicle mobility differentiation. Furthermore, leveraging vehicular communications of VANETs, the mobility-aware real-time path planning can be designed to smooth the vehicle traffic in an ITS, through which the traffic congestion in urban scenarios can be effectively relieved. In addition, with the consideration of the range anxiety caused by mobility, coordinated charging can provide efficient charging plans for electric vehicles (EVs) to improve the overall energy utilization while preventing an electric power system from overloading. To this end, we try to answer the following questions: Q1) How to utilize mobility characteristics of vehicles to derive the achievable asymptotic throughput capacity in pure VANETs? Q2) How to design path planning for mobile vehicles to maximize spatial utility based on mobility differentiation, in order to approach vehicle-traffic capacity in a VANET-enhanced ITS? Q3) How to develop the charging strategies based on mobility of electric vehicles to improve the electricity utility, in order to approach load capacities of charging stations in VANET-enhanced smart grid? To achieve the first objective, we consider the unique features of VANETs and derive the scaling law of VANETs throughput capacity in the data uploading scenario. We show that in both free-space propagation and non-free-space propagation environments, the achievable throughput capacity of individual vehicle scales as $\Theta (\frac{1}{{\log n}}) with$n$denoting the population of a set of homogenous vehicles in the network. To achieve the second objective, we first establish a VANET-enhanced ITS, which incorporates VANETs to enable real-time communications among vehicles, road side units (RSUs), and a vehicle-traffic server in an efficient way. Then, we propose a real-time path planning algorithm, which not only improves the overall spatial utilization of a road network but also reduces average vehicle travel cost for avoiding vehicles from getting stuck in congestion. To achieve the third objective, we investigate a smart grid involved EV fast charging system, with enhanced communication capabilities, i.e., a VANET-enhanced smart grid. It exploits VANETs to support real-time communications among RSUs and highly mobile EVs for real-time vehicle mobility information collection or charging decision dispatch. Then, we propose a mobility-aware coordinated charging strategy for EVs, which not only improves the overall energy utilization while avoiding power system overloading, but also addresses the range anxieties of individual EVs by reducing the average travel cost. In summary, the analysis developed and the scaling law derived in$Q1$of this thesis is practical and fundamental to reveal the relationship between the mobility of vehicles and the network performance in VANETs. And the strategies proposed in$Q2$and$Q3$ of the thesis are meaningful in exploiting/leveraging the vehicle mobility differentiation to improve the system performance in order to approach the corresponding capacities

Recent Advances in Wireless Communications and Networks

This book focuses on the current hottest issues from the lowest layers to the upper layers of wireless communication networks and provides "real-time" research progress on these issues. The authors have made every effort to systematically organize the information on these topics to make it easily accessible to readers of any level. This book also maintains the balance between current research results and their theoretical support. In this book, a variety of novel techniques in wireless communications and networks are investigated. The authors attempt to present these topics in detail. Insightful and reader-friendly descriptions are presented to nourish readers of any level, from practicing and knowledgeable communication engineers to beginning or professional researchers. All interested readers can easily find noteworthy materials in much greater detail than in previous publications and in the references cited in these chapters

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Building the Future Internet through FIRE

The Internet as we know it today is the result of a continuous activity for improving network communications, end user services, computational processes and also information technology infrastructures. The Internet has become a critical infrastructure for the human-being by offering complex networking services and end-user applications that all together have transformed all aspects, mainly economical, of our lives. Recently, with the advent of new paradigms and the progress in wireless technology, sensor networks and information systems and also the inexorable shift towards everything connected paradigm, first as known as the Internet of Things and lately envisioning into the Internet of Everything, a data-driven society has been created. In a data-driven society, productivity, knowledge, and experience are dependent on increasingly open, dynamic, interdependent and complex Internet services. The challenge for the Internet of the Future design is to build robust enabling technologies, implement and deploy adaptive systems, to create business opportunities considering increasing uncertainties and emergent systemic behaviors where humans and machines seamlessly cooperate

Acesso banda larga sem fios em ambientes heterogéneos de próxima geração

Doutoramento em Engenharia InformáticaO acesso ubíquo à Internet é um dos principais desafios para os operadores de telecomunicações na próxima década. O número de utilizadores da Internet está a crescer exponencialmente e o paradigma de acesso "always connected, anytime, anywhere" é um requisito fundamental para as redes móveis de próxima geração. A tecnologia WiMAX, juntamente com o LTE, foi recentemente reconhecida pelo ITU como uma das tecnologias de acesso compatíveis com os requisitos do 4G. Ainda assim, esta tecnologia de acesso não está completamente preparada para ambientes de próxima geração, principalmente devido à falta de mecanismos de cross-layer para integração de QoS e mobilidade. Adicionalmente, para além das tecnologias WiMAX e LTE, as tecnologias de acesso rádio UMTS/HSPA e Wi-Fi continuarão a ter um impacto significativo nas comunicações móveis durante os próximos anos. Deste modo, é fundamental garantir a coexistência das várias tecnologias de acesso rádio em termos de QoS e mobilidade, permitindo assim a entrega de serviços multimédia de tempo real em redes móveis. Para garantir a entrega de serviços multimédia a utilizadores WiMAX, esta Tese propõe um gestor cross-layer WiMAX integrado com uma arquitectura de QoS fim-a-fim. A arquitectura apresentada permite o controlo de QoS e a comunicação bidireccional entre o sistema WiMAX e as entidades das camadas superiores. Para além disso, o gestor de cross-layer proposto é estendido com eventos e comandos genéricos e independentes da tecnologia para optimizar os procedimentos de mobilidade em ambientes WiMAX. Foram realizados testes para avaliar o desempenho dos procedimentos de QoS e mobilidade da arquitectura WiMAX definida, demonstrando que esta é perfeitamente capaz de entregar serviços de tempo real sem introduzir custos excessivos na rede. No seguimento das extensões de QoS e mobilidade apresentadas para a tecnologia WiMAX, o âmbito desta Tese foi alargado para ambientes de acesso sem-fios heterogéneos. Neste sentido, é proposta uma arquitectura de mobilidade transparente com suporte de QoS para redes de acesso multitecnologia. A arquitectura apresentada integra uma versão estendida do IEEE 802.21 com suporte de QoS, bem como um gestor de mobilidade avançado integrado com os protocolos de gestão de mobilidade do nível IP. Finalmente, para completar o trabalho desenvolvido no âmbito desta Tese, é proposta uma extensão aos procedimentos de decisão de mobilidade em ambientes heterogéneos para incorporar a informação de contexto da rede e do terminal. Para validar e avaliar as optimizações propostas, foram desenvolvidos testes de desempenho num demonstrador inter-tecnologia, composta pelas redes de acesso WiMAX, Wi-Fi e UMTS/HSPA.Ubiquitous Internet access is one of the main challenges for the telecommunications industry in the next decade. The number of users accessing the Internet is growing exponentially and the network access paradigm of “always connected, anytime, anywhere” is a central requirement for the so-called Next Generation Mobile Networks (NGMN). WiMAX, together with LTE, was recently recognized by ITU as one of the compliant access technologies for 4G. Nevertheless, WiMAX is not yet fully prepared for next generation environments, mainly due to the lack of QoS and mobility crosslayer procedures to support real-time multimedia services delivery. Furthermore, besides the 4G compliant WiMAX and LTE radio access technologies, UMTS/HSPA and Wi-Fi will also have a significant impact in the mobile communications during the next years. Therefore, it is fundamental to ensure the coexistence of multiple radio access technologies in what QoS and mobility procedures are concerned, thereby allowing the delivery of real-time services in mobile networks. In order to provide the WiMAX mobile users with the demanded multimedia services, it is proposed in this Thesis a WiMAX cross-layer manager integrated in an end-to-end all-IP QoS enabled architecture. The presented framework enables the QoS control and bidirectional communication between WiMAX and the upper layer network entities. Furthermore, the proposed cross-layer framework is extended with media independent events and commands to optimize the mobility procedures in WiMAX environments. Tests were made to evaluate the QoS and mobility performance of the defined architecture, demonstrating that it is perfectly capable of handling and supporting real time services without introducing an excessive cost in the network. Following the QoS and mobility extensions provided for WiMAX, the scope of this Thesis is broaden and a seamless mobility architecture with QoS support in heterogeneous wireless access environments is proposed. The presented architecture integrates an extended version of the IEEE 802.21 framework with QoS support, as well as an advanced mobility manager integrated with the IP level mobility management protocols. Finally, to complete the work within the framework of this Thesis, it is proposed an extension to the handover decisionmaking processes in heterogeneous access environments through the integration of context information from both the network entities and the enduser. Performance tests were developed in a real testbed to validate the proposed optimizations in an inter-technology handover scenario involving WiMAX, Wi-Fi and UMTS/HSPA

Building the Future Internet through FIRE

The Internet as we know it today is the result of a continuous activity for improving network communications, end user services, computational processes and also information technology infrastructures. The Internet has become a critical infrastructure for the human-being by offering complex networking services and end-user applications that all together have transformed all aspects, mainly economical, of our lives. Recently, with the advent of new paradigms and the progress in wireless technology, sensor networks and information systems and also the inexorable shift towards everything connected paradigm, first as known as the Internet of Things and lately envisioning into the Internet of Everything, a data-driven society has been created. In a data-driven society, productivity, knowledge, and experience are dependent on increasingly open, dynamic, interdependent and complex Internet services. The challenge for the Internet of the Future design is to build robust enabling technologies, implement and deploy adaptive systems, to create business opportunities considering increasing uncertainties and emergent systemic behaviors where humans and machines seamlessly cooperate