Supporting Cyber-Physical Systems with Wireless Sensor Networks: An Outlook of Software and Services

Sensing, communication, computation and control technologies are the essential building blocks of a cyber-physical system (CPS). Wireless sensor networks (WSNs) are a way to support CPS as they provide fine-grained spatial-temporal sensing, communication and computation at a low premium of cost and power. In this article, we explore the fundamental concepts guiding the design and implementation of WSNs. We report the latest developments in WSN software and services for meeting existing requirements and newer demands; particularly in the areas of: operating system, simulator and emulator, programming abstraction, virtualization, IP-based communication and security, time and location, and network monitoring and management. We also reflect on the ongoing efforts in providing dependable assurances for WSN-driven CPS. Finally, we report on its applicability with a case-study on smart buildings

an open and modular hardware node for wireless sensor and body area networks

Health monitoring is nowadays one of the hottest markets due to the increasing interest in prevention and treatment of physical problems. In this context the development of wearable, wireless, open-source, and nonintrusive sensing solutions is still an open problem. Indeed, most of the existing commercial architectures are closed and provide little flexibility. In this paper, an open hardware architecture for designing a modular wireless sensor node for health monitoring is proposed. By separating the connection and sensing functions in two separate boards, compliant with the IEEE1451 standard, we add plug and play capabilities to analog transducers, while granting at the same time a high level of customization. As an additional contribution of the work, we developed a cosimulation tool which simplifies the physical connection with the hardware devices and provides support for complex systems. Finally, a wireless body area network for fall detection and health monitoring, based on wireless node prototypes realized according to the proposed architecture, is presented as an application scenario

Internet based data collection and monitoring for wireless sensor networks

Thesis (M.S.) University of Alaska Fairbanks, 2007The omnipresence of the Internet and the advances in integrated circuit technologies has expanded the potential modes of communication and data collection. Adding Internet capabilities to any electronic device greatly extends the device's user interface, allowing the user to remotely configure and monitor the device over the network through the embedded web server. The embedded web server is expected to establish two-way communication and serve dynamic web pages using very limited resources. We adapted an existing embedded web server to allow remote control and monitoring of wireless sensor networks (WSN). This required establishing an interface to the WSN and developing firmware and user programs to communicate with the remote client. An interactive and flexible web-based user management interface is developed to allow the two-way interaction between the remote user and the wireless sensor network. The embedded server generates email alerts to the administrator about critical issues in the WSN, provides secure access to the WSN control modules, etc. Two embedded web servers are developed using different hardware platforms. The first solution is a low cost, energy efficient solution with somewhat limited functionality. The other uses a more powerful microcontroller-based platform and implements a fully-functional, dynamic web server with multiple web pages.1. Introduction -- 2. Embedded web server -- 3. Related studies -- 4. MSP430-based Web Server -- 5. Rabbit-based web server -- 6. Conclusion and future work -- 7. References -- Appendix A: TCP/IP protocol frame formats -- Appendix B: Embedded web server snapshots

Modular hardware platform for monitoring and control at small office and home office

Dissertação de Mestrado em Engenharia Física apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.Este trabalho consistiu no desenvolvimento de uma plataforma modular de hardware para controlo e monitorização, criando, deste modo, a base para a rápida prototipagem de produtos e sensores capazes de se ligarem a Internet. Utilizam-se produtos e dispositivos disponíveis comercialmente para o público em geral na criação da plataforma, como é o caso do Raspberry Pi e de Arduinos, interligados pelos módulos de rádio NRF24L01+. A plataforma desenvolvida foi usada na construção do Qold, um produto para monitorizar temperaturas de forma automática, sem fios e totalmente integrado com uma aplicação online, tendo sido testado num cenário de utilização real, mostrando-se um sistema fiável (80.7% e 74.8% de up time no principal instalação feita). Um total de 5 gateways e 14 nodos foram instalados.In this project it was developed a modular hardware platform for monitoring and control. This platform will allow the faster development of products and sensors able to be connected to the Internet. We used commercial o the shelf products, such as Arduino and Raspberry Pi, and we connected them using the NRF24L01+ radio modules. The created platform was used in the development of Qold, a product designed to automatically measure temperatures and that is totally integrated with a web application. Qold was tested in real situation scenarios, with a reliable performance (with up times of 80.7% and 74.8% in the main pilot tested). A total of 5 gateways and 14 sensor nodes were installed

Leveraging software-defined networking for modular management in wireless sensor networks

Thesis (PhD (Electronics))--University of Pretoria, 2019.Wireless sensor networks (WSNs) are becoming increasingly popular with the advent of the internet of things (IoT). Various real-world applications of WSNs such as in smart grids, smart farming, and smart health would require a potential deployment of thousands or maybe hundreds of thousands of sensor nodes/actuators. To ensure the proper working order and network efficiency of such a network of sensor nodes, an effective WSN management system has to be integrated. However, the inherent challenges of WSNs such as sensor/actuator heterogeneity, application dependency, and resource constraints have led to challenges in implementing effective traditional WSN management. This difficulty in management increases as the WSN becomes larger. Software-defined networking (SDN) provides a promising solution for flexible management of WSNs by allowing the separation of the control logic from the sensor nodes/actuators. The advantage with this SDN-based management in WSNs is that it enables centralized control of the entire WSN making it simpler to deploy network-wide management protocols and applications on demand. Therefore in a comprehensive literature review, this study highlights some of the recent work on traditional WSN management in brief and reviews SDN-based management techniques for WSNs in greater detail. All this while drawing attention towards the advantages that SDN brings to traditional WSN management. This study also investigates open research challenges in coming up with mechanisms for flexible and easier SDN-based WSN configuration and management. A profound research challenge uncovered in the literature review is the need for an SDN-based system that would provide an opportunity for rapid testing and implementation of management modules. Therefore, this study proposes SDNMM, a generic and modular WSN management system based on SDN. SDNMM introduces the concept of management modularity using a management service interface (MSI) that enables management entities to be added as modules. The system leverages the use of SDN in WSNs and by being modular it also allows for rapid development and implementation of IoT applications. The system has been built on an open-source platform to support its generic aspect and a sample resource management module implemented and evaluated to support the proposed modular management approach. Results showed how adding a resource management module via the MSI improved packet delivery, delay, control traffic and energy consumption over comparable frameworks. However, SDN-based implementation comes at a cost of control overhead traffic which is a performance bottleneck in WSNs due to the limited in-band traffic channel bandwidth associated with WSNs. This has driven the research community to look into methods of effectively reducing the overhead control traffic in a process known as control message quenching (CMQ). In this study, a state of the art overview of control traffic reduction techniques available and being implemented for SDN-based WSNs is also presented. It provides an insight on benefits, challenges and open research areas available in the field of control message quenching for SDN-based WSNs. This study opens the door to this widely unexplored research area in its current form. Additionally, this study introduces a neighbour discovery control message quenching (ND-CMQ) algorithm to aid the reduction of neighbour reports in an SDN-based 6LoWPAN framework. The algorithm produces a significant decrease in control traffic and as a result shows improvements in packet delivery rate, packet delay, and energy efficiency compared to not implementing any CMQ algorithm and also compared to an alternative FR-CMQ algorithm based on flow setup requests.Copperbelt University under the ministry of higher education in ZambiaCouncil for Scientific and Industrial Research (CSIR)Electrical, Electronic and Computer EngineeringPhD (Electronics)Unrestricte

Multitasking on Wireless Sensor Networks

A Wireless Sensor Network (WSN) is a loose interconnection among distributed embedded devices called motes. Motes have constrained sensing, computing, and communicating resources and operate for a long period of time on a small energy supply. Although envisioned as a platform for facilitating and inspiring a new spectrum of applications, after a decade of research the WSN is limited to collecting data and sporadically updating system parameters. Programming other applications, including those that have real-time constraints, or designing WSNs operating with multiple applications require enhanced system architectures, new abstractions, and design methodologies. This dissertation introduces a system design methodology for multitasking on WSNs. It allows programmers to create an abstraction of a single, integrated system running with multiple tasks. Every task has a dedicated protocol stack. Thus, different tasks can have different computation logics and operate with different communication protocols. This facilitates the execution of heterogeneous applications on the same WSN and allows programmers to implement a variety of system services. The services that have been implemented provide energy-monitoring, tasks scheduling, and communication between the tasks. The experimental section evaluates implementations of the WSN software designed with the presented methodology. A new set of tools for testbed deployments is introduced and used to test examples of WSNs running with applications interacting with the physical world. Using remote testbeds with over 100 motes, the results show the feasibility of the proposed methodology in constructing a robust and scalable WSN system abstraction, which can improve the run-time performance of applications, such as data collection and point-to-point streaming

A sensor node soC architecture for extremely autonomous wireless sensor networks

Tese de Doutoramento em Engenharia Eletrónica e de Computadores (PDEEC) (especialidade em Informática Industrial e Sistemas Embebidos)The Internet of Things (IoT) is revolutionizing the Internet of the future and the way new smart objects and people are being connected into the world. Its pervasive computing and communication technologies connect myriads of smart devices, presented at our everyday things and surrounding objects. Big players in the industry forecast, by 2020, around 50 billion of smart devices connected in a multitude of scenarios and heterogeneous applications, sharing data over a true worldwide network. This will represent a trillion dollar market that everyone wants to take a share. In a world where everything is being connected, device security and device interoperability are a paramount. From the sensor to the cloud, this triggers several technological issues towards connectivity, interoperability and security requirements on IoT devices. However, fulfilling such requirements is not straightforward. While the connectivity exposes the device to the Internet, which also raises several security issues, deploying a standardized communication stack on the endpoint device in the network edge, highly increases the data exchanged over the network. Moreover, handling such ever-growing amount of data on resource-constrained devices, truly affects the performance and the energy consumption. Addressing such issues requires new technological and architectural approaches to help find solutions to leverage an accelerated, secure and energy-aware IoT end-device communication. Throughout this thesis, the developed artifacts triggered the achievement of important findings that demonstrate: (1) how heterogeneous architectures are nowadays a perfect solution to deploy endpoint devices in scenarios where not only (heavy processing) application-specific operations are required, but also network-related capabilities are major concerns; (2) how accelerating network-related tasks result in a more efficient device resources utilization, which combining better performance and increased availability, contributed to an improved overall energy utilization; (3) how device and data security can benefit from modern heterogeneous architectures that rely on secure hardware platforms, which are also able to provide security-related acceleration hardware; (4) how a domain-specific language eases the co-design and customization of a secure and accelerated IoT endpoint device at the network edge.Internet of Things (IoT) é o conceito que está a revolucionar a Internet do futuro e a forma como coisas, processos e pessoas se conectam e se relacionam numa infraestrutura de rede global que interligará, num futuro próximo, um vasto número de dispositivos inteligentes e de utilização diária. Com uma grande aposta no mercado IoT por parte dos grandes líderes na industria, algumas visões otimistas preveem para 2020 mais de 50 mil milhões de dispositivos ligados na periferia da rede, partilhando grandes volumes de dados importantes através da Internet, representando um mercado multimilionário com imensas oportunidades de negócio. Num mundo interligado de dispositivos, a interoperabilidade e a segurança é uma preocupação crescente. Tal preocupação exige inúmeros esforços na exploração de novas soluções, quer a nível tecnológico quer a nível arquitetural, que visem impulsionar o desenvolvimento de dispositivos embebidos com maiores capacidades de desempenho, segurança e eficiência energética, não só apenas do dispositivo em si, mas também das camadas e protocolos de rede associados. Apesar da integração de pilhas de comunicação e de protocolos standard das camadas de rede solucionar problemas associados à conectividade e a interoperabilidade, adiciona a sobrecarga inerente dos protocolos de comunicação e do crescente volume de dados partilhados entre os dispositivos e a Internet, afetando severamente o desempenho e a disponibilidade do mesmo, refletindo-se num maior consumo energético global. As soluções apresentadas nesta tese permitiram obter resultados que demonstram: (1) a viabilidade de soluções heterogéneas no desenvolvimento de dispositivos IoT, onde não só tarefas inerentes à aplicação podem ser aceleradas, mas também tarefas relacionadas com a comunicação do dispositivo; (2) os benefícios da aceleração de tarefas e protocolos da pilha de rede, que se traduz num melhor desempenho do dispositivo e aumento da disponibilidade do mesmo, contribuindo para uma melhor eficiência energética; (3) que plataformas de hardware modernas oferecem mecanismos de segurança que podem ser utilizados não apenas em prol da segurança do dispositivo, mas também nas capacidades de comunicação do mesmo; (4) que o desenvolvimento de uma linguagem de domínio específico permite de forma mais eficaz e eficiente o desenvolvimento e configuração de dispositivos IoT inteligentes.This thesis was supported by a PhD scholarship from Fundação para a Ciência e Tecnologia, SFRH/BD/90162/201

Software defined networking based resource management and quality of service support in wireless sensor network applications

To achieve greater performance in computing networks, a setup of critical computing aspects that ensures efficient network operation, needs to be implemented. One of these computing aspects is, Quality of Service (QoS). Its main functionality is to manage traffic queues by means of prioritizing sensitive network traffic. QoS capable networking allows efficient control of traffic especially for network critical data. However, to achieve this in Wireless Sensor Networks (WSN) is a serious challenge, since these technologies have a lot of computing limitations. It is even difficult to manage networking resources with ease in these types of technologies, due to their communication, processing and memory limitations. Even though this is the case with WSNs, they have been largely used in monitoring/detection systems, and by this proving their application importance. Realizing efficient network control requires intelligent methods of network management, especially for sensitive network data. Different network types implement diverse methods to control and administer network traffic as well as effectively manage network resources. As with WSNs, communication traffic and network resource control are mostly performed depending on independently employed mechanisms to deal with networking events occurring on different levels. It is therefore challenging to realize efficient network performance with guaranteed QoS in WSNs, given their computing limitations. Software defined networking (SDN) is advocated as a potential paradigm to improve and evolve WSNs in terms of capacity and application. A means to apply SDN strategies to these compute-limited WSNs, formulates software defined wireless sensor networks (SDWSN). In this work, a resource-aware OpenFlow-based Active Network Management (OF-ANM) QoS scheme that uses SDN strategies is proposed and implemented to apply QoS requirements for managing traffic congestion in WSNs. This scheme uses SDN programmability strategies to apply network QoS requirements and perform traffic load balancing to ensure congestion control in SDWSN. Our experimental results show that the developed scheme is able to provide congestion avoidance within the network. It also allows opportunities to implement flexible QoS requirements based on the system’s traffic state. Moreover, a QoS Path Selection and Resource-associating (Q-PSR) scheme for adaptive load balancing and intelligent resource control for optimal network performance is proposed and implemented. Our experimental results indicate better performance in terms of computation with load balancing and efficient resource alignment for different networking tasks when compared with other competing schemes.Thesis (PhD)--University of Pretoria, 2018.National Research FoundationUniversity of PretoriaElectrical, Electronic and Computer EngineeringPhDUnrestricte

An Anthology of Next-Generation WSNs and Transformative IoT Use-Cases

The Internet of Things (IoT) paradigm brought an ever-increasing dependence on low-power devices to collect sensor data and transmit that information to the cloud, placing greater demand on connectivity and lifespan. In response, rapid worldwide innovation demonstrates the trade-offs in processing, communication, and energy consumption with diverse approaches to low-power components, duty-cycle schemes, cost, and many other critical constraints for complex use-cases, such as track-and-trace (T&T). This work explores the central theme of low-power wireless sensor networks (WSNs) in the IoT and Industrial IoT (IIoT). A collection of publications evolves through the theme, from an IoT literature review to enabling densely-scalable WSNs for logistics & asset management (LAM). Next, this research enhances the WSN design by leveraging wake-up radio (WUR) and energy harvesting (EH) to achieve battery-free operation. Lastly, this work presents WSNs to improve visibility and control of airflow/microclimate management in potentially transformative IIoT use-cases, such as data centers and agriculture