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One of the key issues in mobile communication system is how to predict the number of calls per each cell. It is an important parameter and usually assumed as random Poisson value. For effective management of cellular network, the average number of calls should be traced and the changes in the numbers need to be promptly detected. In this paper we propose an algorithm detecting the changes in the behavior of the users using the technique proposed for point-of-change problem based only on the number of call arrivals. Computer simulation reveals that the proposed method can effectively detect the discord, and the developed model is very accurate as showing mostly less than 1% differences. Document type: Part of book or chapter of book

Abstract

Satellite Communications in the 5G Era explores promising scenarios for 5G Satellite Communications (SatCom), novel paradigms for satellite-terrestrial integration and emerging technologies for the next generation of satellite systems and hybrid/integrated satellite-terrestrial systems, and focuses on recent research efforts towards 5G and beyond. Satellite communications plays a vital role in ensuring seamless access to any telecommunications service anytime and anywhere, and is only a viable option for delivering telecommunication services in a wide range of sectors such as aeronautical, military, maritime, rescue and disaster relief. It should be an important component of 5G-and-beyond wireless architectures as it complements terrestrial telecommunication solutions in various scenarios and will ensure the expansion of the 5G ecosystem towards highly reliable and secure global wireless networks.

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Orientador: Leandro Aparecido Villas Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação Made available in DSpace on 2018-08-30T12:25:57Z (GMT). No. of bitstreams: 1 Souza_AllanMarianode_M.pdf: 3090134 bytes, checksum: c9f97502249f7e0f959e5619ca372dcc (MD5) Previous issue date: 2016 Resumo: O congestionamento é um problema grave nas grandes cidades, o qual acaba gerando perdas econômicas, aumento do tempo de viagem e maior emissão de gases poluentes. Umas das principais causas do congestionamento é o aumento súbito do tráfego de veículos durante os horários de pico, acidentes de trânsito e gargalos nas infraestruturas de transporte. Nos últimos anos, com os avanços nas tecnologias de comunicação sem fio e o desenvolvimento de padrões para rede veiculares, tornou-se possível a implementação de Sistemas de Transporte Inteligentes. Os sistemas de transporte inteligentes são soluções abrangentes para gerenciamento de tráfego em tempo real que se baseia, sobretudo, em dados coletados de veículos, infraestruturas de rede disponíveis às margens de ruas, rodovias e de outros sensores que monitoram o trânsito. Uma área de pesquisa promissora para sistemas de transporte inteligentes são as redes veiculares, as quais são um tipo específico de redes móveis, nas quais os nós são formados por veículos com capacidade de processamento, armazenamento e comunicação sem fio. Com esta questão em mente, nessa dissertação são propostos dois sistemas de transporte inteligentes baseados em redes veiculares para detecção e controle de congestionamentos. Em particular, para controlar congestionamentos causados por acidentes de trânsito é proposto o SPARTAN, um sistema capaz de evitar a iminência de congestionamentos em locais de acidente de trânsito, o qual detecta o acidente e alerta os veículos próximos, para que eles alterem suas rotas e evitem passar pelo local do acidente, assim, evitando o surgimento de congestionamentos no local do acidente. Além disso, para controlar congestionamentos causados pelo grande número de veículos nas vias é proposto o COLOSSUS, um sistema capaz de classificar a condição de tráfego das vias, afim de detectar congestionamentos e, por fim, gerenciar o tráfego dos veículos, roteando-os para reduzir e controlar os congestionamentos detectados. Sendo assim, os resultados mostram a eficiência do SPARTAN para controlar congestionamentos causados por acidentes, uma vez que o mesmo reduz o tempo médio de viagem, tempo médio de congestionamento, consumo médio de combustível e emissões de CO em até 62%, 88%, 36% e 35% respectivamente. Por outro lado, a eficiência do COLOSSUS pode ser observada em seus resultados, onde o mesmo reduz o tempo médio de viagem, tempo médio de congestionamento, consumo médio de combustível e emissões de CO em até 34%, 70%, 12% e 11% respectivamente para congestionamentos causados pelo grande número de veículos Abstract: Congestion is a major problem in large cities, which ends up causing economic losses, increases the travel time and increases greenhouse gas emissions. One of the main causes of congestion is sudden increase in vehicle traffic during peak hours, traffic accidents and bottlenecks in transport infrastructure. In recent years, with advances in wireless communication technologies and the development of standards of vehicular ad hoc networks, has became possible the implementation of Intelligent Transportation Systems. Intelligent Transportation Systems are comprehensive solutions for real-time traffic management that is based primarily on data collected from vehicles, network infrastructure and other sensors that monitor the traffic. A promising research area in intelligent transportation systems are vehicular ad hoc networks, which are a specific type of mobile networks in which the nodes are formed by vehicles with processing power, storage, and wireless communication. With this question in mind, this work proposes two intelligent transport systems based on vehicle ad hoc networks for sensing and control congestions. In particular, to control congestion caused by traffic accidents is proposed the SPARTAN, which can avoid the rise of a congestion in accident areas, SPARTAN detects the accident and warns oncoming vehicles, so they change their routes and avoid to pass in the congestion area, thus avoiding the rise of a congestion in an accident area. Furthermore, to control congestion caused by the large number of vehicles on the roads is proposed COLOSSUS, a system that are able to classify the traffic condition in all roads in order to detect congestion and, finally, manage traffic of vehicles, routing them to reduce and control the detected congestion. Thus, the results of SPARTAN showed their effectiveness for controlling congestions caused by accident, since it reduces the average travel time, average congestion time, average fuel consumption and CO emissions by 62% 88% 36% and 35% respectively. On the other hand, the COLOSSUS efficiency can be seen in its results, where it reduces the average travel time, average time of congestion, average fuel consumption and CO emissions by up to 34% 70% 12% and 11% respectively for congestion caused by large number of vehicles on the roads Mestrado Ciência da Computação Mestre em Ciência da Computação 132901/2015-3 CNPQ

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Orientadores: Leandro Aparecido Villas, Edmundo Roberto Mauro Madeira Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Computação Made available in DSpace on 2020-02-07T18:33:19Z (GMT). No. of bitstreams: 1 Akabane_AdemarTakeo_D.pdf: 8120275 bytes, checksum: cd6482ee4f51bb13e31c71d5350d9fc7 (MD5) Previous issue date: 2019 Resumo: Devido à atual tendência mundial de urbanização, a sociedade moderna enfrenta, cada vez mais, sérios problemas de mobilidade urbana. Além disso, com o aumento constante do fluxo de tráfego veicular, as atuais soluções existentes para gerenciamento de tráfego se tornaram ineficientes. Com isso, para atender às crescentes necessidades dos sistemas de transporte, é necessário sistemas de transporte inteligentes (ITS). O desenvolvimento de ITS sustentável requer integração e interoperabilidade contínuas com tecnologias emergentes, tais como as redes veiculares (VANETs). As VANETs são consideradas uma tecnologia promissora que provê aplicações críticas de segurança e serviços de entretenimento, consequentemente melhorando a experiência de viagem do motorista e dos passageiros. Esta tese propõe um sistema de gerenciamento de tráfego de veículos sem a necessidade de uma infraestrutura de apoio. Para alcançar o sistema desejado foram necessários propor soluções intermediárias que contribuíram nesta tese. A primeira contribuição reside em uma solução que emprega conhecimento histórico dos padrões de mobilidade dos motoristas para obter uma visão global da situação da rede viária. Diferentemente de outras abordagens que precisam de troca constante de informações entre os veículos e o servidor central, nossa solução utiliza informações espaciais e temporais sobre padrões de mobilidade, além das informações específicas da infraestrutura viária, a fim de identificar congestionamentos no tráfego, permitindo, assim, o planejamento de roteamento de veículos. Como segunda contribuição, foi proposta uma solução distribuída para calcular a intermediação egocêntrica nas VANETs. Por meio da métrica egocêntrica foi proposto um mecanismo inovador de ranqueamento de veículos em redes altamente dinâmicas. As principais vantagens desse mecanismo para aplicações de VANETs são: (i) a redução do consumo de largura de banda e (ii) a superação do problema de topologias altamente dinâmicas. A terceira contribuição é uma solução de planejamento de rotas colaborativo com intuito de melhorar o gerenciamento do tráfego de veículos em cenários urbanos. Como última contribuição, esta tese integra as soluções descritas acima, propondo um sistema eficiente de gerenciamento de tráfego de veículos. As soluções propostas foram amplamente comparadas com outras soluções da literatura em diferentes métricas de avaliação de desempenho. Os resultados mostram que o sistema de gerenciamento de tráfego de veículos proposto é eficiente e escalável, qual pode ser uma boa alternativa para mitigar os problemas de mobilidade urbana Abstract: Due to the current global trend of urbanization, modern society is facing severe urban mobility problems. In addition, considering the constant increase in vehicular traffic on roads, existing traffic management solutions have become inefficient. In order to assist the increasing needs of transport systems today, there is a need for intelligent transportation systems (ITS). Developing a sustainable ITS requires seamless integration and interoperability with emerging technologies such as vehicular ad-hoc networks (VANETs). VANETs are considered to be a promising technology providing access to critical life-safety applications and infotainment services, consequently improving drivers¿ and passengers¿ on-road experiences. This thesis proposes an infrastructure-less vehicular traffic management system. To achieve such a system, intermediate solutions that contributed to this thesis were proposed. The first contribution lies in a solution that employs historical knowledge of driver mobility patterns to gain an overall view of the road network situation. Unlike other approaches that need constant information exchange between vehicles and the central server, our solution uses space and temporal information about mobility patterns, as well as road infrastructure information, in order to identify traffic congestion, thus allowing for vehicle routing planning. Secondly, a distributed solution to calculate egocentric betweenness in VANETs was proposed. Through the egocentric metric, an innovative vehicle ranking mechanism in highly dynamic networks was proposed. The main advantages of this mechanism for VANETs applications are (i) reduced bandwidth consumption and (ii) overcoming the problem of highly dynamic topologies. The third contribution is a collaborative route planning solution designed to improve vehicle traffic management in urban settings. As the last contribution, this thesis integrates the solutions described above, proposing an efficient vehicle traffic management system. The proposed solutions were widely compared with other literature solutions on different performance evaluation metrics. The evaluation results show that the proposed vehicle traffic management system is efficient, scalable, and cost-effective, which may be a good alternative to mitigate urban mobility problems Doutorado Ciência da Computação Doutor em Ciência da Computação 2015/25588-6 FAPESP

Abstract

© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Resilience and high availability are considered as essential requirements in 5G networks. To fullfil these requirements, the integration of a satellite component within mobile backhaul networks arises as a compelling proposition to provide backup connectivity to critical cell sites and divert traffic from congested areas so that a limited capacity in their terrestrial links could be supplemented during peak-time or even replaced in case of total/partial failure or maintenance. This is especially of interest for public protection and disaster relief (PPDR) communications in remote/rural areas that might require the fast deployment of nework capacity as well as in distressed areas where the terrestrial backhaul infrastructure might have suffered damages. This paper first describes an architectural framework that enables the integration and management of the satellite capacity as a constituent part of a Software Defined Networking (SDN) -based traffic engineered mobile backhaul network. Then, a SDN-based Traffic Engineering (TE) application is proposed to manage some amount of dynamically steerable satellite capacity provisioned for resilience purposes to maximize a network utility function under both failure and nonfailure conditions in the terrestrial links. Numerical results are presented to assess the benefits of the proposed TE application and its performance is compared to that of a traditional overflow solution. Peer Reviewed

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This paper discusses some challenges that user mobility imposes over the user-centric protection model against security threats. This model is based on the idea of offloading the security applications from the end user device, and placing them in a trusted network node at the network's edge. Our research perspective is particularly centered around three interrelated mobility challenges, i) the allocation of the security applications “close” to the user, i.e., on network nodes with enhanced processing capabilities, ii) seamless mobility with negligible disruption of ongoing network connections, and iii) dynamic orchestration and management with support of security applications migration. Based on our arguments, we expose the main requirements and trade-offs to be considered in the attempt to support mobility in such environment. We propose a flexible solution that leverages Software Defined Networking, Network Function Virtualization and Computing at the Network Edge to offer a seamless on-path security protection to mobile users. Our preliminary experiments' results considering a WiFi mobile user show that seamless security migration and mobility are feasible in a simple real scenario. Vertical mobility and more complex use cases scenarios are envisioned for future research. Peer Reviewed Document type: Conference object