Avec les progrès dans les communications sans fil, le réseau maillé sans fils (WMN) est apparu comme une solution à la couverture et à la capacité limitée des réseaux d'infrastructure. Un WMN est un réseau ad-hoc multi-sauts dans lequel les routeurs participants acheminent le trafic pour le compte de tiers. Malgré les avantages et l'efficacité accrue de nombreuses applications, plusieurs problèmes doivent encore être résolus, notamment des facteurs critiques influant sur les performances des WMNs tels que l'évolutivité, la stabilité de la connectivité réseau, la qualité de service, la sécurité et les problèmes d'interférence. Face à ce défi, cette thèse explore une nouvelle approche des réseaux, à savoir le concept de réseau défini par logiciel (SDN). Dans une configuration SDN, l'intelligence située au niveau des périphériques réseau est déplacée dans une entité centrale communément appelée le contrôleur SDN. Dans cette architecture, le contrôleur SDN prend toutes les décisions et dicte à chaque périphérique réseau comment router les flux de données. Dans cette thèse, l'accent est mis sur l'évaluation des améliorations de la gestion de réseau que SDN pourrait apporter aux WMNs. En particulier, nous avons analysé et déterminé le type de granularité de contrôle SDN envisageable pour ce type de réseaux ainsi que les solutions techniques permettant de mettre en œuvre ce concept pour de meilleures performances. / With advances in wireless communications, Wireless Mesh Network (WMN) has emerged as one solution to the limited coverage and capacity of infrastructure networks. A WMN is a multihop ad-hoc network where participating routers forward traffic on behalf of others. Despite the advantages and increased efficiency in many applications, several challenges still need to be solved and especially critical factors influencing the performance of WMNs such as scalability, network connectivity steadiness, Quality of Service (QoS), security, and interference problems. In the face of this challenge, this thesis explores a new approach for networks, namely the concept of Software-Defined Network (SDN). In an SDN configuration, the intelligence located at network devices level is moved within a central entity commonly referred to as the SDN controller. In this architecture, the SDN controller takes all decisions and dictates to each network device how to route data flows. In this thesis, the focus is on evaluating network management improvements that SDN could make in WMNs. Particularly, we analyzed and determined what kind of SDN control granularity that could be envisaged for this type of networks as well as the technical solutions to implement this concept for better performance.

In the context of the Internet of Things (IoT), commissioning is the process of securely adding a new device to a network. It covers many different tasks, including the physical deployment of devices and configuration of parameters. It is network installers who need to manually commission each device one by one with the help of commissioning tools. In practice, the first task for a network installer is to identify each device correctly before configuring it with proper parameters. Individually identifying each device, especially in a large network, is a very time-consuming process. This is also known as the identification problem. This project is going to address the problem.A novel device identification approach is presented in the thesis, and there is no human intervention involved in the identification process. Devices are trying to identify themselves based on predefined rules and given information. The approach is therefore called device self-identification, and it is implemented in two different algorithms. One is the centralized device selfidentification, and the other is the distributed device self-identification. In short, only one device participates in the device identification process in the centralized approach, and in the distributed counterpart, every device is part of the identification process.The results of the implementations show the potential of the new way to identify devices in IoT. Devices in both the centralized approach and the distributed approach are able to identify themselves given necessary information about the network. A detailed discussion regarding the two proposed algorithms and the network information is presented in the thesis. / I samband med Internet of Things (IoT) är igångkörning processen att säkert lägga till en ny enhet i ett nätverk. Den täcker många olika uppgifter, inklusive fysisk distribution av enheter och konfigurering av parametrar. Det är nätverksinstallatörer som måste manuellt beställa varje enhet en efter en med hjälp av installationsverktyg. I praktiken är den första uppgiften för en nätverksinstallatör att korrekt identifiera varje enhet innan den konfigureras med lämpliga parametrar. Att identifiera varje enhet speciellt i ett stort nätverk är en mycket tidskrävande process. Detta är också känt som identifieringsproblemet. Detta projekt kommer att ta itu med problemet.En nyhetsidentifieringsmetod presenteras i avhandlingen och det finns ingen mänsklig intervention involverad i identifieringsprocessen. Enheter försöker identifiera sig baserat på fördefinierade regler och information. Tillvägagångssättet kallas därför enhetens självidentifiering och det implementeras i två olika algoritmer, en är centraliserad enhetens självidentifiering och den andra är distribuerad enhetens självidentifiering. Kort sagt, endast en enhet deltar i enhetsidentifieringsprocessen i centraliserat tillvägagångssätt, och i distribuerad motsvarighet är varje enhet en del av identifieringsprocessen.Resultaten av implementationerna visar potentialen för det nya sättet att identifiera enheter i IoT. Enheter i både centraliserat tillvägagångssätt och distribuerat tillvägagångssätt kan identifiera sig med den information som krävs för nätverket. En detaljerad diskussion om de två föreslagna algoritmerna och nätverksinformationen presenteras i avhandlingen.

This thesis presents the work of a master degree project in mechatronics by two students from The Royal Institute of Technology. The project was carried out during spring 2017 in collaboration with Bosch Rexroth Mellansel as part of their desire to improve their operations. It is also in line with the Bosch Groups ambition to lead the development within Industry 4.0. The aim was to investigate the information need on a discrete manufacturing process and how radio-frequency identification (RFID) can be used to cover that need. The background research was made with qualitative methods using a literature review on relevant areas and a case study of Bosch Rexroth Mellansel. A discrete event simulation was created to confirm the possibilities of an RFID tracking system. It acted as a target for what the developed demonstrator should fulfil and was realised through a system of four wireless nodes connected in a mesh network. The plant in Mellansel partially implemented a Bosch standardised RFID system in parallel with the development of the demonstrator, which enabled a comparison of the two systems. The results show that from a tag event, which gives information on what, where and when, it is possible to, in real time, analyse and visualise valuable key performance indicators for a production process. It is also possible to use the data to automate transactions in an enterprise resource system which removes non-value adding activities from an operator while also ensuring consistency in the reporting procedure. The results indicate that benefits can be achieved. However, this requires further quantitative analysis before it can be fully confirmed and be used to push the development of Industry 4.0 forward. / Denna rapport presenterar ett examensarbete inom mekatronik av två studenter från Kungliga Tekniska Högskolan. Projektet genomfördes under våren 2017 i samarbete med Bosch Rexroth Mellansel som en del av deras strävan att förbättra sin verksamhet. Det ligger också i linje med Bosch koncernens ambition att leda utvecklingen inom Industri 4.0. Syftet var att undersöka informationsbehovet hos en diskret tillverkningsprocess och hur radio-frequency identification (RFID) kan användas för att täcka detta behov. Bakgrundsstudien gjordes med kvalitativa metoder som litteraturstudie inom relevanta områden och en fallstudie av en produktionsprocess inom Bosch Rexroth Mellansel. En simulering av produktionsprocessen skapades för att bekräfta möjligheterna av att använda ett RFID system för spårning av objekt. Den fungerade som ett mål för vad den utvecklade demonstratorn skulle uppfylla och realiserades genom en prototyp bestående av fyra trådlösa noder samlade i ett mesh nätverk. Parallellt med utvecklingen av demonstratorn gemomförde fabriken i Mellansel en del-implementering av en Bosch-standardiserad RFID lösning, vilket möjliggjorde en jämförelse av de två systemen. Resultaten visar att det från en avläsning av en tag, som ger information om vad, var och när, så är möjligt att i realtid analysera och visualisera värdefulla nyckeltal för en produktionsprocess. Det är också möjligt att använda data för att automatisera transaktioner i ett affärssystem som tar bort icke värdeskapande aktiviteter för operatören och samtidigt säkerställer en standardiserad rapporteringsprocess. Resultaten visar att fördelar kan uppnås men kräver ytterligare kvantitativ analys innan de kan bekräftas till fullo och användas för att driva utvecklingen av Industri 4.0 framåt.

This thesis presents an exploratory study into the development of digital societies and it examines public sector modernization and innovation from a technology management perspective. The study presents reasons why most city-wide or council-wide development of wireless broadband access networks currently end in failure or are unsustainable. It also suggests its links with wider problems of innovation management and the commercial failure of otherwise technically competent solutions It explores the modernisation of society, government, the underlying theories that influence it as well as the innovations triggered by its wake. The exercise reveals a myriad of innovations; firstly in the modernisation of the infrastructure of government and secondly in the development of societal infrastructure in the form of broadband networks.

<p>Solar energy is a clean and abundant renewable energy source which is currently used in many types of photovoltaic (PV) designs. In practical PV systems, solar panels are used to harvest solar energy and convert it into a usable form of electricity. Due to the intermittent nature of solar energy input however, battery storage, in combination with solar panels, must be used to provide an uninterrupted source of power.</p> <p>The process of assigning solar panel and battery configurations for a PV system is referred to as energy resource provisioning. Unfortunately, energy provisioning costs are still relatively high, and this is one of the main obstacles that inhibits the adoption of solar power for many applications. These costs however, can be substantially reduced through cost-efficient resource provisioning methods. The focus of this thesis is on the development of efficient algorithms and energy management methods that will reduce energy provisioning costs in solar powered systems.</p> <p>First, we consider resource provisioning in solar powered wireless mesh networks. In practical solar powered systems, there are usually restrictions in the way that the mesh nodes can be positioned, and this results in a time-varying and node-dependent attenuation of the available solar energy. Unfortunately, conventional resource provisioning methods cannot take this into account and therefore the deployed system may be unnecessarily expensive. In this part of the thesis, the resource provisioning problem is considered from this point of view. We first review conventional resource provisioning mechanisms and give an example which shows the value of introducing positional solar insolation awareness. A Position Aware Provisioning (PAP) algorithm is then introduced that takes known positional variations into consideration when performing the energy provisioning. Simulation results show that reductions in total network provisioning cost can be obtained using the proposed methodology compared to conventional algorithms.</p> <p>In the second part of the thesis, we consider communication infrastructure that is operated from the power grid with a solar powered addition. Resource provisioning and energy management algorithms are introduced to minimize the capital expenditure (CAPEX) and operating expenditure (OPEX) costs. We first derive lower bounds on the costs using a linear programming (LP) formulation where solar components are sized using solar insolation and projected loading data. A variety of different node configurations are considered. Three energy scheduling algorithms are then introduced to optimize online OPEX costs, namely, Grid Purchase Last (GPL), Solar Load Optimization (SLO) and Solar Load Simulation (SLS) algorithms. Simulation results show the extent to which a solar powered add-on can reduce total cost.</p> <p>Finally, we consider solar powered systems where part of their energy demands are deferrable, up to some maximum tolerable delay. The objective is to exploit the flexibility of deferrable energy demands in a way that decreases the total provisioning cost. A mixed integer linear optimization program is derived which gives a lower bound on the provisioning cost. A Delay Aware Provisioning (DAP) algorithm is then proposed to determine practical cost-efficient energy provisioning. The performance of DAP is compared to the provisioning bound and the conventional Stand-alone Node Provisioning (SNP) algorithm. Results are presented which show the significant provisioning cost savings that can be obtained.</p> / Doctor of Philosophy (PhD)

The power grid has changed a great deal from what has been generally viewed as a traditional power grid. The modernization of the power grid has seen an increase in the integration and incorporation of computing and communication elements, creating an interdependence of both physical and cyber assets of the power grid. The fast-increasing connectivity has transformed the grid from what used to be primarily a physical system into a Cyber- Physical System (CPS). The physical elements within a power grid are well understood by power engineers; however, the newly deployed cyber aspects are new to most researchers and operators in this field. The new computing and communications structure brings new vulnerabilities along with all the benefits it provides. Cyber security of the power grid is critical due to the potential impact it can make on the community or society that relies on the critical infrastructure. These vulnerabilities have already been exploited in the attack on the Ukrainian power grid, a highly sophisticated, multi-layered attack which caused large power outages for numerous customers. There is an urgent need to understand the cyber aspects of the modernized power grid and take the necessary precautions such that the security of the CPS can be better achieved. The power grid is dependent on two main cyber infrastructures, i.e., Supervisory Control And Data Acquisition (SCADA) and Advanced Metering Infrastructure (AMI). This thesis investigates the AMI in power grids by developing a testbed environment that can be created and used to better understand and develop security strategies to remove the vulnerabilities that exist within it. The testbed is to be used to conduct and implement security strategies, i.e., an Intrusion Detections Systems (IDS), creating an emulated environment to best resemble the environment of the AMI system. A DoS flooding attack and an IDS are implemented on the emulated testbed to show the effectiveness and validate the performance of the emulated testbed. / M.S. / The power grid is becoming more digitized and is utilizing information and communication technologies more, hence the smart grid. New systems are developed and utilized in the modernized power grid that directly relies on new communication networks. The power grid is becoming more efficient and more effective due to these developments, however, there are some considerations to be made as for the security of the power grid. An important expectation of the power grid is the reliability of power delivery to its customers. New information and communication technology integration brings rise to new cyber vulnerabilities that can inhibit the functionality of the power grid. A coordinated cyber-attack was conducted against the Ukrainian power grid in 2015 that targeted the cyber vulnerabilities of the system. The attackers made sure that the grid operators were unable to observe their system being attacked via Denial of Service attacks. Smart meters are the digitized equivalent of a traditional energy meter, it wirelessly communicates with the grid operators. An increase in deployment of these smart meters makes it such that we are more dependent on them and hence creating a new vulnerability for an attack. The smart meter integration into the power grid needs to be studied and carefully considered for the prevention of attacks. A testbed is created using devices that emulate the smart meters and a network is established between the devices. The network was attacked with a Denial of Service attack to validate the testbed performance, and an Intrusion detection method was developed and applied onto the testbed to prove that the testbed created can be used to study and develop methods to cover the vulnerabilities present.

In this thesis the possibilities of smart antenna systems in wireless mesh networks are examined. With respect to the individual smart antenna tradeoffs, a routing protocol (Modified HWMP, MHWMP) for IEEE 802.11s mesh networks is presented, that exploits the full range of benefits provided by smart antennas: MHWMP actively switches between the PHY-layer transmission/reception modes (multiplexing, beamforming and diversity) according to the wireless channel conditions. Spatial multiplexing and beamforming are used for unicast data transmissions, while antenna diversity is employed for efficient broadcasts. To adapt to the directional channel environment and to take full benefit of the PHY capabilities, a respective MAC scheme is employed. The presented protocol is tested in extensive simulation and the results are examined.

In this thesis the possibilities of smart antenna systems in wireless mesh networks are examined. With respect to the individual smart antenna tradeoffs, a routing protocol (Modified HWMP, MHWMP) for IEEE 802.11s mesh networks is presented, that exploits the full range of benefits provided by smart antennas: MHWMP actively switches between the PHY-layer transmission/reception modes (multiplexing, beamforming and diversity) according to the wireless channel conditions. Spatial multiplexing and beamforming are used for unicast data transmissions, while antenna diversity is employed for efficient broadcasts. To adapt to the directional channel environment and to take full benefit of the PHY capabilities, a respective MAC scheme is employed. The presented protocol is tested in extensive simulation and the results are examined.:1 Introduction 2 Wireless Mesh Networks 3 IEEE 802.11s 4 Smart Antenna Concepts 5 State of the Art: Wireless Mesh Networks with Smart Antennas 6 New Concepts 7 System Model 8 Results and Discussion 9 Conclusion and Future Work

近年來興起一個前瞻性無線技術，稱之為無線網狀網路（Wireless Mesh Networks），WMNs 以所費低廉方式提供無線網路最後一哩存取Internet，同時具備ad hoc 網路全部優點，例如自我組織（self-organization）、自我組態（self-configuration）等。儘管WMNs 骨幹部分與平面式ad hoc 網路相似，多網卡（multi-radio）的Mesh Routers 節點卻是固定不動且沒有電力限制。有鑑於此，設計於ad hoc 網路上之路由協定並不適合於WMNs。 WCETT（Weighted Cumulated Expected Transmission Time）metric 考量到intra-flow 干擾，卻未捕捉到inter-flow 干擾；而LBAR（Load-Balanced Ad hoc Routing）協定以計算節點之活躍值（nodal activity）與訊務流量干擾選擇路徑，並無支援多網卡路由，LBAR 可以在單一網卡環境表現良好，在多網卡環境卻不一定。因此，我們提出一個WMNs 上考量到Intra/Inter-flow干擾之多網卡路由協定，稱為MiRii。模擬結果顯示出我們路由協定可以改善網路效能，包含了封包成功傳送率及平均點對點延遲。 / A new promising wireless technology has emerged recently, called wireless mesh networks (WMNs). WMNs are inexpensive way to provide wireless last-mile broadband Internet access and have all the advantages of ad hoc network, such as self-organization, self-configuration. Although WMNs backbone is similar to flat ad hoc network, mesh routers with multi-radio are stationary and have no power constraints. As a result, routing protocols designed for ad hoc network may not be appropriate for WMNs. The WCETT (Weighted Cumulated Expected Transmission Time) metric takes intra-flow interference into consideration, but does not capture inter-flow interference. LBAR (Load-Balanced Ad hoc Routing) calculates nodal activity and traffic interference for choosing a path, but does not supporting multi-radio. LBAR may be perform well in single-radio environment, but do not perform as well in multi-radios. Consequently, we incorporate a new Multi-Interface Routing with Intra/Inter-flow Interference in Wireless Mesh Networks, called MiRii. The simulations show that our routing protocol can improve the network performance including the Packet Delivery Ratio and average end-to-end delay.

Approved for public release, distribution is unlimited / Wireless mesh networking has emerged as the successor of the traditional ad hoc networks. New technological advances, the standardization of protocols and interfaces and the maturity of key components have made it possible for current mesh research groups to set goals that are really close to the world's expectations. The objective of this research is to design and implement a simulation toolkit for wireless mesh clusters that can be used as an additional performance evaluation technique for the Tactical Network Topology program of Naval Postgraduate School. This toolkit is implemented in the OPNET simulation environment and it incorporates various nodes running different ad hoc routing protocols. Furthermore, the investigation of a suitable combination of protocols for the Tactical Network Topology is achieved by creating scenarios and running a number of simulations using the mesh toolkit. / Captain, Hellenic Air Force