Net-Opp : um middleware transparente para formação de redes e troca de conteúdos para aplicações oportunistas.

Programa de Pós-Graduação em Ciência da Computação. Departamento de Ciência da Computação, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto.O avanço e popularização de dispositivos móveis e a integração de novos recursos de comunicação possibilitaram o surgimento das redes oportunistas. Rede oportunista é um tipo de rede que promove uma comunicação entre dois dispositivos móveis mesmo que uma rota para conectá-los não exista. Esse processo é feito através de oportunidades de encontros não programados entre dispositivos móveis que trocam dados entre si até que a mensagem chegue ao destinatário. Essa comunicação de encontros em redes oportunistas permitiu diversas aplicações, como na redução de tráfego de rede celular, em comunicações em situação de emergência, e no contorno a censura de comunicação. O crescente aumento de dispositivos móveis deve, em tese, promover redes oportunistas, já que com mais dispositivos, maiores possibilidades de encontros será possível. Porém, na prática, as tecnologias atuais para redes oportunistas não estão disponíveis (Wi-Fi Ad-Hoc) nos dispositivos móveis atuais ou exigem interação indesejada (Bluetooth e Wi-Fi Direct) do usuário para estabelecer conectividade. Para superar essas deficiências é apresentado o middleware Net-Opp. Baseado na tecnologia Wi-Fi modo infraestrutura, onde o dispositivo se torna um ponto de acesso, Net-Opp pesquisa e analisa pontos de acesso disponíveis no ambiente, e se encontrar se associa com um ponto. Se nenhum ponto de acesso for encontrado, Net-Opp torna o dispositivo em um ponto de acesso, no modo infraestrutura, para prover uma rede de comunicação para outros dispositivos, possibilitando uma troca transparente de conteúdos entre os dispositivos, já que neste modo de operação do Wi-Fi não é exigido pareamento (associação entre dispositivos). Esse processo realizado por Net-Opp é feito automaticamente sem exigir interação humana e alteração no sistema operacional dos dispositivos móveis. Como prova de conceito e avaliação são apresentadas duas aplicações que empregam o uso da arquitetura desse middleware. As aplicações foram desenvolvidas em cenários de dispositivos móveis pessoais e veiculares. O principal objetivo dessas aplicações é a avaliação do middleware Net-Opp em cenários reais e diferentes e provar que esse processo de alternância entre escaneamento e ponto de acesso pode promover uma comunicação transparente ao usuário final. Resultados de avaliações nas aplicações demonstraram que o middleware conseguiu criar uma camada de interoperabilidade entre o sistema operacional e as aplicações oportunistas, e abstrair a formação da rede e a troca de conteúdos entre vários dispositivos simultaneamente de forma transparente nos dois cenários.The advancement and popularization of mobile devices and the integration of new communication capabilities made possible the emergence of opportunistic networks. Opportunistic network is a type of network that promotes communication between two mobile devices even if a route to connect them does not exist. This process is done through meetings opportunities unscheduled between mobile devices that exchange data with each other until the message reaches the recipient. This communication meetings in opportunistic networks allow various applications, such as the reduction of mobile network traffic, communications in emergency situations, and outline the censorship of communication. The increasing number of mobile devices should, in theory, promote opportunistic networks, as more devices, more likely to meetings will be possible. However, in practice, current technologies for opportunistic networks are not available (Wi-Fi Ad-Hoc) in today’s mobile devices or require unwanted interaction (Bluetooth and Wi-Fi Direct) User to establish connectivity. To overcome these shortcomings is shown the Net-Opp middleware. Based on Wi-Fi technology infrastructure mode, where the device becomes a point of access, Net-Opp research and analyzes access points available in the environment, and meet associates with a point. If no access point is found, Net-Opp makes the device in an access point in infrastructure mode, to provide a communications network to other devices, enabling a transparent exchange of content between devices, since in this operating mode Wi-Fi is not required pairing (association between devices). This process carried out by Net-Opp is done automatically without requiring human interaction and change in operating system for mobile devices. As proof of concept and evaluation are presented two applications that employ the use of this middleware architecture. The applications were developed in scenarios of personal and vehicular mobile devices. The main purpose of these applications is the evaluation of the Net-Opp middleware in real and different scenarios and prove that this process of switching between scanning and access point can promote transparent communication to the end user. Results of assessments in applications showed that the middleware has managed to create a layer of interoperability between the operating system and opportunistic applications, and abstract the formation of the network and the exchange of content among multiple devices simultaneously transparently in both scenarios

Counting time in drops : views on the role and importance of smartwatches in dew computing.

A large amount of data, called the big data, generated by the devices that are part of the Internet of Things, is expected in the coming years. This scenario creates challenges for sending, processing, and storing all data centrally in the cloud. Recent works propose a decentralization of the processing and storage of this data in local devices close to the user to solve such challenges. This paradigm, called dew computing, has been gaining attention from academia. Several works apply this proposal through devices such as desktops, laptops, and smartphones. However, after a systematic review, no studies were found that applied this proposal to smart wearable devices. Thus, this work shows the research, evaluation, analysis, and discussion of smartwatches for the dew computing environment. The results of this work showed that smartwatches could extend local device functionalities through performing services, cooperating with decentralizing cloud computing, and helping to reduce the negative impacts of the big data

Transparent Sharing Architecture of Content Between Mobile Devices in Opportunistic Networks

Opportunistic networks are one of the most interesting developments of MANETs, which allow various applications, such as downloading the mobile traffic, communications in emergency situations and contour censorship. The increasing number of mobile devices should, in theory, promote opportunistic networks. However, in practice, current technologies for opportunistic networks, such as Wi-Fi ad-hoc, Bluetooth and Wi-Fi Direct, or are not available in current devices, or unwanted require user interaction to establish connectivity. To overcome these shortcomings, we propose an architecture that uses the Wi-Fi infrastructure mode in order to promote communication between devices, allowing the transparent exchange without user interaction content. Two applications that employ the use of this architecture are presented. The first, from personal devices, proved to be scalable in tests with up to nine devices. The second, vehicles, proved to be feasible when applied in scenarios with low speed, generating a low packet loss and high transmission rates

CoWPar: A D2D Communication Approach Without Pairing for Mobile Social Network in Proximity

Mobile devices and the cellular network have been popularized and evolving in recent years. The increase of these devices may promote Device-to-Device (D2D) communications. However, current D2D communication technologies such as Wi-Fi Direct, Wi-Fi Ad Hoc, and Bluetooth are not available on devices or require human interaction in the pairing process. In addition, the cellular network is not available in many places and has partial or total communication infrastructure failures. To overcome this failure and lack of connectivity, and to allow D2D communication between devices in disturbing scenarios, we presented CoWPar. Based on the Wi-Fi infrastructure mode, CoWPar establishes the connection and performs data exchange without human interaction between the devices. Results of experiments performed in a proof of concept showed in practice that CoWPar allowed D2D communications with no pairing and also without the need to change the operating system (OS) of the devices, surpassing all the works available so far and thus contributing to the process of viabilization the paradigm of Pervasive Computing

D2D pervasive communication system with out-of-band control autonomous to 5G networks.

D2D (device-to-device) communication is one of the developments of 5G networks (5th generation mobile networks) that reduce mobile traffic load, reduce energy consumption and effectively use the available electrical radio spectrum. An increase in the number of mobile devices might, in theory, promote D2D communications to 5G networks; however, in practice, the D2D communications technologies, such as Wi-Fi Ad-Hoc, Bluetooth and Wi-Fi Direct, are not available or require human interaction. To overcome these limitations, a middleware based on Wi-Fi infrastructure mode, which establishes connections and performs data exchange without human interaction, is presented. Practical proofs of the concept demonstrate that the middleware enables transparent D2D communications for 5G applications

IoT Registration and Authentication in Smart City Applications with Blockchain

The advent of 5G will bring a massive adoption of IoT devices across our society. IoT Applications (IoT Apps) will be the primary data collection base. This scenario leads to unprecedented scalability and security challenges, with one of the first areas for these applications being Smart Cities (SC). IoT devices in new network paradigms, such as Edge Computing and Fog Computing, will collect data from urban environments, providing real-time management information. One of these challenges is ensuring that the data sent from Edge Computing are reliable. Blockchain has been a technology that has gained the spotlight in recent years, due to its robust security in fintech and cryptocurrencies. Its strong encryption and distributed and decentralized network make it potential for this challenge. Using Blockchain with IoT makes it possible for SC applications to have security information distributed, which makes it possible to shield against Distributed Denial of Service (DDOS). IoT devices in an SC can have a long life, which increases the chance of having security holes caused by outdated firmware. Adding a layer of identification and verification of attributes and signature of messages coming from IoT devices by Smart Contracts can bring confidence in the content. SC Apps that extract data from legacy and outdated appliances, installed in inaccessible, unknown, and often untrusted urban environments can benefit from this work. Our work's main contribution is the development of API Gateways to be used in IoT devices and network gateway to sign, identify, and authorize messages. For this, keys and essential characteristics of the devices previously registered in Blockchain are used. We will discuss the importance of this implementation while considering the SC and present a testbed that is composed of Blockchain Ethereum and real IoT devices. We analyze the transfer time, memory, and CPU impacts during the sending and processing of these messages. The messages are signed, identified, and validated by our API Gateways and only then collected for an IoT data management application