Дисертації: "Fog Communications and Computing"

1

Butterfield, Ellis H. "Fog Computing with Go: A Comparative Study." Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/cmc_theses/1348.

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The Internet of Things is a recent computing paradigm, de- fined by networks of highly connected things – sensors, actuators and smart objects – communicating across networks of homes, buildings, vehicles, and even people. The Internet of Things brings with it a host of new problems, from managing security on constrained devices to processing never before seen amounts of data. While cloud computing might be able to keep up with current data processing and computational demands, it is unclear whether it can be extended to the requirements brought forth by Internet of Things. Fog computing provides an architectural solution to address some of these problems by providing a layer of intermediary nodes within what is called an edge network, separating the local object networks and the Cloud. These edge nodes provide interoperability, real-time interaction, routing, and, if necessary, computational delegation to the Cloud. This paper attempts to evaluate Go, a distributed systems language developed by Google, in the context of requirements set forth by Fog computing. Similar methodologies of previous literature are simulated and benchmarked against in order to assess the viability of Go in the edge nodes of Fog computing architecture.

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2

Mebrek, Adila. "Fog Computing pour l’Internet des objets." Thesis, Troyes, 2020. http://www.theses.fr/2020TROY0028.

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Le Fog Computing constitue une approche prometteuse dans le contexte de l’Internet des Objets (IoT) car il fournit des fonctionnalités et des ressources à l’extrémité du réseau, plus près des utilisateurs finaux. Cette thèse étudie les performances du Fog Computing dans le cadre des applications IoT sensibles à la latence. La première problématique traitée concerne la modélisation mathématique d’un système IoT-fog-cloud, ainsi que les métriques de performances du système en termes d’énergie consommée et de latence. Cette modélisation nous permettra par la suite de proposer diverses stratégies efficaces de distribution de contenu et d’allocation des ressources dans le fog et le cloud. La deuxième problématique abordée dans cette thèse concerne la distribution de contenu et de données des objets dans des systèmes fog/cloud. Afin d’optimiser simultanément les décisions d’offloading et d’allocation des ressources du système, nous distinguons entre deux types d’applications IoT : (1) applications IoT à contenu statique ou avec des mises à jour peu fréquentes ; et (2) applications IoT à contenu dynamique. Pour chaque type d’application, nous étudions le problème d’offloading de requêtes IoT dans le fog. Nous nous concentrons sur les problèmes d'équilibrage de charge afin de minimiser la latence et l’énergie totale consommée par le système
Fog computing is a promising approach in the context of the Internet of Things (IoT) as it provides functionality and resources at the edge of the network, closer to end users. This thesis studies the performance of fog computing in the context of latency sensitive IoT applications. The first issue addressed is the mathematical modeling of an IoT-fogcloud system, and the performance metrics of the system in terms of energy consumed and latency. This modeling will then allow us to propose various effective strategies for content distribution and resource allocation in the fog and the cloud. The second issue addressed in this thesis concerns the distribution of content and object data in fog / cloud systems. In order to simultaneously optimize offloading and system resource allocation decisions, we distinguish between two types of IoT applications: (1) IoT applications with static content or with infrequent updates; and (2) IoT applications with dynamic content. For each type of application, we study the problem of offloading IoT requests in the fog. We focus on load balancing issues to minimize latency and the total power consumed by the system

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3

Erman, Maria. "Applications of Soft Computing Techniques for Wireless Communications." Licentiate thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-17314.

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This thesis presents methods and applications of Fuzzy Logic and Rough Sets in the domain of Telecommunications at both the network and physical layers. Specifically, the use of a new class of functions, the truncated π functions, for classifying IP traffic by matching datagram size histograms is explored. Furthermore, work on adapting the payoff matrix in multiplayer games by using fuzzy entries as opposed to crisp values that are hard to quantify, is presented. Additionally, applications of fuzzy logic in wireless communications are presented, comprised by a comprehensive review of current trends and applications, followed by work directed towards using it in spectrum sensing and power control in cognitive radio networks. This licentiate thesis represents parts of my work in the fields of Fuzzy Systems and Wireless Communications. The work was done in collaboration between the Departments of Applied Signal Processing and Mathematics at Blekinge Institute of Technology.

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4

Badokhon, Alaa. "An Adaptable, Fog-Computing Machine-to-Machine Internet of Things Communication Framework." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1492450137643915.

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5

Wiss, Thomas. "Evaluation of Internet of Things Communication Protocols Adapted for Secure Transmission in Fog Computing Environments." Thesis, Mittuniversitetet, Avdelningen för informationssystem och -teknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-35298.

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A current challenge in the Internet of Things is the seeking after conceptual structures to connect the presumably billions of devices of innumerable forms and capabilities. An emerging architectural concept, the fog cloud computing, moves the seemingly unlimited computational power of the distant cloud to the edge of the network, closer to the potentially computationally limited things, effectively diminishing the experienced latency. To allow computationally-constrained devices partaking in the network they have to be relieved from the burden of constant availability and extensive computational execution. Establishing a publish/subscribe communication pattern with the utilization of the popular Internet of Things application layer protocol Constrained Application Protocol is depicted one approach of overcoming this issue. In this project, a Java based library to establish a publish/subscribe communication pattern for the Constrained Application Protocol was develop. Furthermore, efforts to build and assess prototypes of several publish/subscribe application layer protocols executed over varying common as well as secured versions of the standard and non-standard transport layer protocols were made to take advantage, evaluate, and compare the developed library. The results indicate that the standard protocol stacks represent solid candidates yet one non-standard protocol stack is the considered prime candidate which still maintains a low response time while not adding a significant amount of communication overhead.

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6

Kaghazchi, Hassan. "A diagnostics model for industrial communications networks." Thesis, University of Sunderland, 2015. http://sure.sunderland.ac.uk/5651/.

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Over the past twenty years industrial communications networks have become common place in most industrial plants. The high availability of these networks is crucial in smooth plant operations. Therefore local and remote diagnostics of these networks is of primary importance in solving any existing or emerging network problems. Users for most part consider the “plant networks” as black boxes, and often not sure of the actual health of the networks. The major part of the work outlined in this research concentrates on the proposed “Network Diagnostics Model” for local and remote monitoring. The main objective of the research is to aid the establishment of tools and techniques for diagnosis of the industrial networks, with particular emphasis on PROFIBUS and PROFINET. Additionally this research has resulted in development of a number of devices to aid in network diagnostics. The work outlined in this submission contributes to the developments in the area of online diagnostics systems. The development work was conducted in the following phases: 1. Development of Function Block (FB) for diagnosing PROFIBUS network for implementation on PLC. 2. Development of OPC server for diagnosing PROFIBUS network for implementation on PC. 3. Development of a web based diagnostic software for multiple fieldbuses for implementation on imbedded XP platform. 4. Development of OPC server for diagnosing PROFINET network for implementation on PC 5. Conformance testing of masters (PLC) in PROFIBUS network to increase the health of the network. 6. Use of diagnostics tools for performance analysis of fieldbuses networks for high performance applications. The research work outlined in this submission has made a significant and coherent contribution to online diagnostics of fieldbus communications networks, and has paved the way for the introduction of the online diagnostics devices to the market place. It has shown that the proposed model provides a uniform framework for research and development of diagnostics tools and techniques for fieldbus networks. Organizations that use fieldbus should consider installing advanced online diagnostic systems to boost maintenance efficiency and reduce operating costs, and maintain the availability of plant resources. Based on the experience gained over a number of years a multilayer model is proposed for future development of diagnostics tools.

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7

Rough, Justin, and mikewood@deakin edu au. "A Platform for reliable computing on clusters using group communications." Deakin University. School of Computing and Mathematics, 2001. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20060412.141015.

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Shared clusters represent an excellent platform for the execution of parallel applications given their low price/performance ratio and the presence of cluster infrastructure in many organisations. The focus of recent research efforts are on parallelism management, transport and efficient access to resources, and making clusters easy to use. In this thesis, we examine reliable parallel computing on clusters. The aim of this research is to demonstrate the feasibility of developing an operating system facility providing transport fault tolerance using existing, enhanced and newly built operating system services for supporting parallel applications. In particular, we use existing process duplication and process migration services, and synthesise a group communications facility for use in a transparent checkpointing facility. This research is carried out using the methods of experimental computer science. To provide a foundation for the synthesis of the group communications and checkpointing facilities, we survey and review related work in both fields. For group communications, we examine the V Distributed System, the x-kernel and Psync, the ISIS Toolkit, and Horus. We identify a need for services that consider the placement of processes on computers in the cluster. For Checkpointing, we examine Manetho, KeyKOS, libckpt, and Diskless Checkpointing. We observe the use of remote computer memories for storing checkpoints, and the use of copy-on-write mechanisms to reduce the time to create a checkpoint of a process. We propose a group communications facility providing two sets of services: user-oriented services and system-oriented services. User-oriented services provide transparency and target application. System-oriented services supplement the user-oriented services for supporting other operating systems services and do not provide transparency. Additional flexibility is achieved by providing delivery and ordering semantics independently. An operating system facility providing transparent checkpointing is synthesised using coordinated checkpointing. To ensure a consistent set of checkpoints are generated by the facility, instead of blindly blocking the processes of a parallel application, only non-deterministic events are blocked. This allows the processes of the parallel application to continue execution during the checkpoint operation. Checkpoints are created by adapting process duplication mechanisms, and checkpoint data is transferred to remote computer memories and disk for storage using the mechanisms of process migration. The services of the group communications facility are used to coordinate the checkpoint operation, and to transport checkpoint data to remote computer memories and disk. Both the group communications facility and the checkpointing facility have been implemented in the GENESIS cluster operating system and provide proof-of-concept. GENESIS uses a microkernel and client-server based operating system architecture, and is demonstrated to provide an appropriate environment for the development of these facilities. We design a number of experiments to test the performance of both the group communications facility and checkpointing facility, and to provide proof-of-performance. We present our approach to testing, the challenges raised in testing the facilities, and how we overcome them. For group communications, we examine the performance of a number of delivery semantics. Good speed-ups are observed and system-oriented group communication services are shown to provide significant performance advantages over user-oriented semantics in the presence of packet loss. For checkpointing, we examine the scalability of the facility given different levels of resource usage and a variable number of computers. Low overheads are observed for checkpointing a parallel application. It is made clear by this research that the microkernel and client-server based cluster operating system provide an ideal environment for the development of a high performance group communications facility and a transparent checkpointing facility for generating a platform for reliable parallel computing on clusters.

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8

Wong, Ford Long. "Protocols and technologies for security in pervasive computing and communications." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611992.

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9

Chan, Ka Chun. "A dual channel location estimation system for mobile computing." HKBU Institutional Repository, 2003. http://repository.hkbu.edu.hk/etd_ra/445.

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10

Chen, Xuetao. "Resource Allocation for Wireless Distributed Computing Networks." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77054.

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Wireless distributed computing networks (WDCNs) will become the next frontier of the wireless industry as the performance of wireless platforms is being increased every year and wireless industries are looking for "killer" applications for increased channel capacity. However, WDCNs have several unique problems compared with currently well-investigated methods for wireless sensor networks and wired distributed computing. For example, it is difficult for WDCNs to be power/energy efficient considering the uncertainty and heterogeneity of the wireless environment. In addition, the service model has to take account of the interference-limited feature of wireless channels to reduce the service delay. Our research proposes a two-phase model for WDCNs including the service provision phase and the service access phase according to different traffic patterns and performance requirements. For the service provision phase, we investigate the impact of communication channel conditions on the average execution time of the computing tasks within WDCNs. We then discuses how to increase the robustness and power efficiency for WDCNs subject to the impact of channel variance and spatial heterogeneity. A resource allocation solution for computation oriented WDCNs is then introduced in detail which mitigates the effects of channel variations with a stochastic programming solution. Stochastic geometry and queue theory are combined to analyze the average performance of service response time and to design optimal access strategies during the service access phase. This access model provides a framework to analyze the service access performance and evaluate whether the channel heterogeneity should be considered. Based on this analysis, optimal strategies to access the service nodes can be determined in order to reduce the service response time. In addition, network initialization and synchronization are investigated in order to build a multiple channel WDCN in dynamic spectrum access (DSA) environments. Further, an efficient primary user detection method is proposed to reduce the channel vacation latency for WDCNs in DSA environments. Finally, this dissertation presents the complete design and implementation of a WDCN on COgnitive Radio Network (CORNET). Based on SDR technologies, software dedicated to WDCNs is designed and implemented across the PHY layer, MAC layer, and application layer. System experiments are carried out to demonstrate the performance issues and solutions presented in this dissertation. Wireless distributed computing networks (WDCNs) will become the next frontier of the wireless industry as the performance of wireless platforms is being increased every year and wireless industries are looking for "killer" applications for increased channel capacity. However, WDCNs have several unique problems compared with currently well-investigated methods for wireless sensor networks and wired distributed computing. For example, it is difficult for WDCNs to be power/energy efficient considering the uncertainty and heterogeneity of the wireless environment. In addition, the service model has to take account of the interference-limited feature of wireless channels to reduce the service delay. Our research proposes a two-phase model for WDCNs including the service provision phase and the service access phase according to different traffic patterns and performance requirements. For the service provision phase, we investigate the impact of communication channel conditions on the average execution time of the computing tasks within WDCNs. We then discuses how to increase the robustness and power efficiency for WDCNs subject to the impact of channel variance and spatial heterogeneity. A resource allocation solution for computation oriented WDCNs is then introduced in detail which mitigates the effects of channel variations with a stochastic programming solution. Stochastic geometry and queue theory are combined to analyze the average performance of service response time and to design optimal access strategies during the service access phase. This access model provides a framework to analyze the service access performance and evaluate whether the channel heterogeneity should be considered. Based on this analysis, optimal strategies to access the service nodes can be determined in order to reduce the service response time. In addition, network initialization and synchronization are investigated in order to build a multiple channel WDCN in dynamic spectrum access (DSA) environments. Further, an efficient primary user detection method is proposed to reduce the channel vacation latency for WDCNs in DSA environments. Finally, this dissertation presents the complete design and implementation of a WDCN on COgnitive Radio Network (CORNET). Based on SDR technologies, software dedicated to WDCNs is designed and implemented across the PHY layer, MAC layer, and application layer. System experiments are carried out to demonstrate the performance issues and solutions presented in this dissertation.
Ph. D.

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11

Kore, Anand. "Using idle workstations for distributed computing." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176488008.

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12

Liu, Huanjin. "Free roaming: A system for ubiquitous computing." CSUSB ScholarWorks, 2006. https://scholarworks.lib.csusb.edu/etd-project/3062.

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Based on the Umbilical Cord system, this project enriches the Ubiquitous Computing system with a Free Roaming system. This Free Roaming consists of a distributed authentication system, a data caching system and a communication system between them. It allows user to roam within this system and access his data everywhere. Together with the Umbilical Cord system, a Ubiquitous Computing system is functionally completed as a prototype, and is ready to be deployed into the Internet.

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13

Cui, Zheng. "Design and implementation of secure communications for a distributed mobile computing system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0016/MQ57103.pdf.

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14

Hossain, Nadir. "Efficiency limiting processes in novel laser materials for optical computing and communications applications." Thesis, University of Surrey, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581801.

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The novel Ga(NAsP)-based semiconductors have recently grown in popularity due to applications such as development of energy efficient long-term stable semiconductor lasers on silicon substrates for optical computing applications. GaAsSb-based active materials have also recently been extensively investigated for the development of temperature stable uncooled semiconductor lasers for 1.3 !-lm optical communications applications. Electrical injection lasing operation at room temperature (RT) is demonstrated in Ga(NAsP) / GaP quantum well (QW) lasers with a threshold current density, J th of 4 kA/ cm2 at the lasing wavelength of 981 nm: From temperature dependence measurements we find that the threshold current is dominated by non-radiative recombination process(es), which account for at least 92% of Jth at RT. The characteristic temp_erature, To (TI) is measured to be ~104K (~99K) around 200K, which drops to ~58K (~37K) aroundRT. Hydrostatic pressure measurements reveal a strong increase in threshold current with increasing pressure. This . implies that current leakage dominates carrier recombination, which is also responsible for their low characteristic temperatures, To and TI at RT. The band-structure properties of novel BxGal_xP alloys are also investigated. These layers are utilized as strain-compensating layers for the lattice-matched integration of Ga(NAsP) . quantum well lasers on an exact (001) silicon substrate. Experimental and-theoretical studies reveal the dependence of the direct and indirect band gaps for strained BxGal_xP layers grown on silicon as a function of Boron composition from which we derive the properties of free- standing BxGal_xP' For Boron fractions up to 6%. We find that the bowing parameter for the lowest (indirect) band gap is -6.2±0.2 eV. High crystalline quality and promising optical material properties are demonstrated and applied to monolithically integrated Ga(NAsP) / (BGa)P multi-quantum well heterostructures on (001) silicon substrates. Electrical injection lasing operation is demonstrated for the first time up to 165K in Ga(NAsP) / (BGa)P QW lasers monolithically integrated on a (001) silicon substrate. The devices show aJth of 1.6 kA/ cm' at the lasing wavelength of 860 nm at 165 K. The To (TI) in the devices is ~198K (~99K) at 100 K;decreasing to ~73K (~35 K) at 165 K. Temperature dependence of the "Z" analysis shows that Zth increases from 1.7 at 40 K to 2.3 at 165 K. The value of Zth < 2 at low temperatures signifies that the monomolecular (defect) current contribution at threshold in these devices is significant. The non-radiative contribution accounts for ~ 83% (of which at least ~40% is monomolecular recombination) of Jth even at a low temperature of 165K. It is proposed that defects originate due to the non-optimized miscut angle of the silicon substrate and due to diffusion of Nitrogen from active region to the barrier regions. A strong increase in Jth with increasing pressure at 165K suggests the presence of, carrier leakage. The temperature and press~e dependence of Jth for GaAsSb/GaAs QW lasers with different device characteristics are investigated. Thermally activated carrier leakage via defects is observed in the GaAsSb/GaAs QW devices. Devices grown under optimal conditions reduce the nonradiative recombination mechanism from 93% to 76% at RT, compared with a device grown under non-optimized conditions. This improvement in carrier recombination mechanisms leads to a large improvement in the Jth from 533 Acm-2/QW to 138 Acm-2/QW and the characteristic temperature, To (TI) from ~51K (~104K) to ~62K (~138K) near RT.

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15

Delgado, Javier. "A grid computing network platform for enhanced data management and visualization." FIU Digital Commons, 2007. http://digitalcommons.fiu.edu/etd/2766.

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This thesis presents a novel approach towards providing a collaboration environment by using Grid Computing. The implementation includes the deployment of a cluster attached to a mural display for high performance computing and visualization and a Grid-infrastructure for sharing storage space across a wide area network and easing the remote use of the computing resources. A medical data processing application is implemented on the platform. The outcome is enhanced use of remote storage facilities and quick return time for computationally-intensive problems. The central issue of this thesis work is thus one that focuses on the development of a secure distributed system for data management and visualization to respond to the need for more efficient interaction and collaboration between technical researchers and medical professionals. The proposed networked solution is envisioned such as to provide synergy for more collaboration on theoretical and experimental issues involving analysis, visualization, and data sharing across sites.

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16

Soto, Garcia Victor. "Mobility-Oriented Data Retrieval for Computation Offloading in Vehicular Edge Computing." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38836.

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Vehicular edge computing (VEC) brings the cloud paradigm to the edge of the network, allowing nodes such as Roadside Units (RSUs) and On-Board Units (OBUs) in vehicles to perform services with location awareness and low delay requirements. Furthermore, it alleviates the bandwidth congestion caused by the large amount of data requests in the network. One of the major components of VEC, computation offloading, has gained increasing attention with the emergence of mobile and vehicular applications with high-computing and low-latency demands, such as Intelligent Transportation Systems and IoT-based applications. However, existing challenges need to be addressed for vehicles' resources to be used in an efficient manner. The primary challenge consists of the mobility of the vehicles, followed by intermittent or lack of connectivity. Therefore, the MPR (Mobility Prediction Retrieval) data retrieval protocol proposed in this work allows VEC to efficiently retrieve the output processed data of the offloaded application by using both vehicles and road side units as communication nodes. The developed protocol uses geo-location information of the network infrastructure and the users to accomplish an efficient data retrieval in a Vehicular Edge Computing environment. Moreover, the proposed MPR Protocol relies on both Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) communication to achieve a reliable retrieval of data, giving it a higher retrieval rate than methods that use V2I or V2V only. Finally, the experiments performed show the proposed protocol to achieve a more reliable data retrieval with lower communication delay when compared to related techniques.

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17

Thraskias, Christos A., Eythimios N. Lallas, Niels Neumann, Laurent Schares, Bert J. Offrein, Ronny Henker, Dirk Plettemeier, Frank Ellinger, Juerg Leuthold, and Ioannis Tomkos. "Survey of Photonic and Plasmonic Interconnect Technologies for Intra-Datacenter and High-Performance Computing Communications." Institute of Electrical and Electronics Engineers (IEEE), 2018. https://tud.qucosa.de/id/qucosa%3A35391.

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Large scale data centers (DC) and high performance computing (HPC) systems require more and more computing power at higher energy efficiency. They are already consuming megawatts of power, and a linear extrapolation of trends reveals that they may eventually lead to unrealistic power consumption scenarios in order to satisfy future requirements (e.g., Exascale computing). Conventional complementary metal oxide semiconductor (CMOS)-based electronic interconnects are not expected to keep up with the envisioned future board-to-board and chip-to-chip (within multi-chip-modules) interconnect requirements because of bandwidth-density and power-consumption limitations. However, low-power and high-speed optics-based interconnects are emerging as alternatives for DC and HPC communications; they offer unique opportunities for continued energy-efficiency and bandwidth-density improvements, although cost is a challenge at the shortest length scales. Plasmonics-based interconnects on the other hand, due to their extremely small size, offer another interesting solution for further scaling operational speed and energy efficiency. At the device-level, CMOS compatibility is also an important issue, since ultimately photonics or plasmonics will have to be co-integrated with electronics. In this paper, we survey the available literature and compare the aforementioned interconnect technologies, with respect to their suitability for high-speed and energy-efficient on-chip and offchip communications. This paper refers to relatively short links with potential applications in the following interconnect distance hierarchy: local group of racks, board to board, module to module, chip to chip, and on chip connections. We compare different interconnect device modules, including low-energy output devices (such as lasers, modulators, and LEDs), photodetectors, passive devices (i.e., waveguides and couplers) and electrical circuitry (such as laserdiode drivers, modulator drivers, transimpedance, and limiting amplifiers). We show that photonic technologies have the potential to meet the requirements for selected HPC and DC applications in a shorter term. We also present that plasmonic interconnect modules could offer ultra-compact active areas, leading to high integration bandwidth densities, and low device capacitances allowing for ultra-high bandwidth operation that would satisfy the application requirements further into the future.

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18

Ahmed, Kishwar. "Energy Demand Response for High-Performance Computing Systems." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3569.

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Анотація:

The growing computational demand of scientific applications has greatly motivated the development of large-scale high-performance computing (HPC) systems in the past decade. To accommodate the increasing demand of applications, HPC systems have been going through dramatic architectural changes (e.g., introduction of many-core and multi-core systems, rapid growth of complex interconnection network for efficient communication between thousands of nodes), as well as significant increase in size (e.g., modern supercomputers consist of hundreds of thousands of nodes). With such changes in architecture and size, the energy consumption by these systems has increased significantly. With the advent of exascale supercomputers in the next few years, power consumption of the HPC systems will surely increase; some systems may even consume hundreds of megawatts of electricity. Demand response programs are designed to help the energy service providers to stabilize the power system by reducing the energy consumption of participating systems during the time periods of high demand power usage or temporary shortage in power supply. This dissertation focuses on developing energy-efficient demand-response models and algorithms to enable HPC system's demand response participation. In the first part, we present interconnection network models for performance prediction of large-scale HPC applications. They are based on interconnected topologies widely used in HPC systems: dragonfly, torus, and fat-tree. Our interconnect models are fully integrated with an implementation of message-passing interface (MPI) that can mimic most of its functions with packet-level accuracy. Extensive experiments show that our integrated models provide good accuracy for predicting the network behavior, while at the same time allowing for good parallel scaling performance. In the second part, we present an energy-efficient demand-response model to reduce HPC systems' energy consumption during demand response periods. We propose HPC job scheduling and resource provisioning schemes to enable HPC system's emergency demand response participation. In the final part, we propose an economic demand-response model to allow both HPC operator and HPC users to jointly reduce HPC system's energy cost. Our proposed model allows the participation of HPC systems in economic demand-response programs through a contract-based rewarding scheme that can incentivize HPC users to participate in demand response.

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19

Mastin, Alan. "Human-Machine Interface for Tactical Air Traffic Control Communications." UNF Digital Commons, 1990. http://digitalcommons.unf.edu/etd/133.

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Анотація:

This thesis proposes the design for a prototype device that would be used by Air Traffic Controllers in the radar environment to input tactical Air Traffic Control (ATC) instructions to be sent to aircraft via the Mode S digital data link network. The purpose of the device is to reduce the time required to issue instructions and to eliminate misunderstandings that occur when instructions are issued over voice transmission frequencies. The purpose of this thesis was to develop the device in the most ergonomically suited manner based on the air traffic controller's communications requirements. Digital communications systems include both airborne and ground based components. This project was concerned with the development of the ground-based aspect of the communications system.

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20

Bozios, Athanasios. "Fog Computing : Architecture and Security aspects." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-80178.

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Анотація:

As the number of Internet of Things (IoT) devices that are used daily is increasing, the inadequacy of cloud computing to provide neseccary IoT-related features, such as low latency, geographic distribution and location awareness, is becoming more evident. Fog computing is introduced as a new computing paradigm, in order to solve this problem by extending the cloud‟s storage and computing resources to the network edge. However, the introduction of this new paradigm is also confronted by various security threats and challenges since the security practices that are implemented in cloud computing cannot be applied directly to this new architecture paradigm. To this end, various papers have been published in the context of fog computing security, in an effort to establish the best security practices towards the standardization of fog computing. In this thesis, we perform a systematic literature review of current research in order to provide with a classification of the various security threats and challenges in fog computing. Furthermore, we present the solutions that have been proposed so far and which security challenge do they address. Finally, we attempt to distinguish common aspects between the various proposals, evaluate current research on the subject and suggest directions for future research.

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21

Machado, Miguel Chagas Bilhau. "Monitoring system based on fog computing." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23462.

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Анотація:

Mestrado em Engenharia de Computadores e Telemática
This thesis is a contribution of an architectural solution, describing a system that represents an extra layer of computing power, placed between the cloud and sensor networks, acting both as a mediator whose central task is to manage, monitor and collect data from geographically-located groups of sensor nodes and as a communication hub to the cloud with which data is exchanged in a compact and minimalist fashion. The latter is accomplished by designing nodes as autonomous entities, able to organise themselves in smaller groups, within the system. Additionally, these entities possess inherent mechanisms which aim to accomplish fault tolerance within groups of nodes, maintaining the status quo of the overall system while performing in an ubiquitous environment, continuously embracing contextual changes. The overall solution was tested in a proof of concept where we conceived three test cases that helped us validate it.
Este documento apresenta uma arquitectura como solução para o desenvolvimento de uma camada extra de poder computacional entre os serviços na núvem e a Internet das Coisas, denominada de computação no nevoeiro. Esta camada é responsável pela gestão e recolha de dados provenientes de conjuntos de sensores, geograﬁcamente distribuídos, em níveis inferiores. Assim, o nevoeiro permite servir como ponto de agregação comunicando directamente com a núvem, minimizando a quantidade de tráfego na rede. A solução descreve a camada de nevoeiro como um conjunto de grupos de nós que se agrupam e organizam como um todo, autonomamente. Existem ainda mecanismos auxiliares que permitem a existência de um certo grau de tolerância a falhas de forma a manter o status quo do sistema em ambientes ubíquos, lidando com as constantes alterações de contexto. A solução foi testada e validada através de uma prova de conceito onde foram realizados três casos de teste, concebidos de forma a abranger todos os componentes da mesma.

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22

Rahafrouz, Amir. "Distributed Orchestration Framework for Fog Computing." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-77118.

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The rise of IoT-based system is making an impact on our daily lives and environment. Fog Computing is a paradigm to utilize IoT data and process them at the first hop of access network instead of distant clouds, and it is going to bring promising applications for us. A mature framework for fog computing still lacks until today. In this study, we propose an approach for monitoring fog nodes in a distributed system using the FogFlow framework. We extend the functionality of FogFlow by adding the monitoring capability of Docker containers using cAdvisor. We use Prometheus for collecting distributed data and aggregate them. The monitoring data of the entire distributed system of fog nodes is accessed via an API from Prometheus. Furthermore, the monitoring data is used to perform the ranking of fog nodes to choose the place to place the serverless functions (Fog Function). The ranking mechanism uses Analytical Hierarchy Processes (AHP) to place the fog function according to resource utilization and saturation of fog nodes’ hardware. Finally, an experiment test-bed is set up with an image-processing application to detect faces. The effect of our ranking approach on the Quality of Service is measured and compared to the current FogFlow.

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23

Davis, Don, Toby Bennett, and Jay Costenbader. "RECONFIGURABLE GATEWAY SYSTEMS FOR SPACE DATA NETWORKING." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/608358.

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Анотація:

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California
Over a dozen commercial remote sensing programs are currently under development representing billions of dollars of potential investment. While technological advances have dramatically decreased the cost of building and launching these satellites, the cost and complexity of accessing their data for commercial use are still prohibitively high. This paper describes Reconfigurable Gateway Systems which provide, to a broad spectrum of existing and new data users, affordable telemetry data acquisition, processing and distribution for real-time remotely sensed data at rates up to 300 Mbps. These Gateway Systems are based upon reconfigurable computing, multiprocessing, and process automation technologies to meet a broad range of satellite communications and data processing applications. Their flexible architecture easily accommodates future enhancements for decompression, decryption, digital signal processing and image / SAR data processing.

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24

Grandi, Stefano. "Sviluppo di Servizi Android per applicazioni Fog Computing." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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Il Cloud Computing è stata la risposta alla crescente domanda di capacità di calcolo, di memorizzazione di dati e di flessibilità nel loro approvvigionamento. Ma se da un lato il Cloud ha permesso di sopperire alle limitazioni hardware a cui i dispositivi utente sono sottoposti, questo nuovo paradigma soffre inevitabilmente di quelle che sono le latenze dovute allo scambio di informazioni attraverso Internet. Inoltre la rete Internet, già messa a dura prova dal continuo e crescente traffico dati, non ha beneficiato dell'utilizzo del paradigma Cloud e teme quello che si appresta a diventare di vastissimo ambito di utilizzo, il paradigma dell'Internet of Things (IoT), per il quale si intende una famiglia di tecnologie il cui scopo è rendere qualunque tipo di oggetto, un dispositivo collegato ad Internet. È proprio in questo scenario che nasce il paradigma del Fog Computing, cioè l'idea di costruire la stessa architettura del Cloud, fisicamente più vicina ai client che, a causa delle loro scarse capacità di elaborazione, memoria o autonomia energetica, necessitano di demandare al Cloud l'esecuzione di operazioni costose. Il Fog si pone quindi l'obiettivo di ridurre al minimo la latenza nelle comunicazioni tra i client e i nodi Fog (dispositivi fisici che si occupano dell'esecuzione delle richieste di servizi), permettendo ai client, di non sottostare più agli svantaggi dovuti alla comunicazione Internet che si hanno con il Cloud, e scaricando quindi la rete Internet di traffico in eccesso. Il progetto di tesi ha quindi visto lo sviluppo di una applicazione Android, chiamata Fog Network Application, in grado di creare e gestire una Fog Network, cioè una rete virtuale, interna alla rete locale LAN, alla quale tutti i dispositivi in possesso dell'applicazione siano in grado di connettersi, quindi fornire dei servizi generici e/o tramite la definizione di una interfaccia, e infine richiedere l'utilizzo di tali servizi.

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25

Civolani, Lorenzo. "Fast Docker Container Deployment in Fog Computing infrastructures." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17701/.

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I contenitori software, meglio noti come container, realizzano ambienti virtuali in cui molteplici applicazioni possono eseguire senza il rischio di interferire fra di loro. L'efficienza e la semplicità dell'approccio hanno contribuito al forte incremento della popolarità dei contaier, e, tra le varie implementazioni disponibili, Docker è di gran lunga quella più diffusa. Sfortunatamente, a causa delle loro grandi dimensioni, il processo di deployment di un container da un registro remoto verso una macchina in locale tende a richiedere tempi lunghi. La lentezza di questa operazione è particolarmente svantaggiosa in un'architettura Fog computing, dove i servizi devono muoversi da un nodo all'altro in risposta alla mobilità degli utenti. Tra l'altro, l'impiego di server a basse prestazioni tipico di tale paradigma rischia di aggravare ulteriormente i ritardi. Questa tesi presenta FogDocker, un sistema che propone un approccio originale all'operazione di download delle immagini Docker con l'obiettivo di ridurre il tempo necessario per avviare un container. L'idea centrale del lavoro è di scaricare soltanto il contenuto essenziale per l'esecuzione del container e procedere immediatamente con l'avvio; poi, in un secondo momento, mentre l'applicazione è già al lavoro, il sistema può proseguire col recupero della restante parte dell'immagine. I risultati sperimentali confermano come FogDocker sia in grado di raggiungere una riduzione notevole del tempo necessario per avviare un container. Tale ottimizzazione si rivela essere particolarmente marcata quando applicata in un contesto a risorse computazionali limitate. I risultati ottenuti dal nostro sistema promettono di agevolare l'adozione dei software container nelle architetture di Fog computing, dove la rapidità di deployment è un fattore di vitale importanza.

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26

Valieri, Mario. "Dynamic Resource and Service Discovery in Fog Computing." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/22265/.

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The cloud computing is already a well-known paradigm, known and used in both business and consumers areas. It provides a lot of advantages, but today the necessity of data security and low latency is rapidly increasing. Nowadays, in next generation networks (NGN), the fog computing paradigm is able to satisfy strict latency and security requirements using distributed computational power. In a dynamic fog orchestration scenario, the discovery of available resources and services is a fundamental aspect to achieve a good quality system. This thesis is focused on the study and comparison of service and node discovery techniques and protocols, with the aim of finding an optimal solution to the problem related to a preexisting fog service orchestration system. Once the optimal solution is detected, a working implementation is proposed and evaluated with appropriate experimental measurements, particularly relevant for network administration.

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27

Struhar, Vaclav. "Improving Soft Real-time Performance of Fog Computing." Licentiate thesis, Mälardalens högskola, Inbyggda system, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55679.

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Fog computing is a distributed computing paradigm that brings data processing from remote cloud data centers into the vicinity of the edge of the network. The computation is performed closer to the source of the data, and thus it decreases the time unpredictability of cloud computing that stems from (i) the computation in shared multi-tenant remote data centers, and (ii) long distance data transfers between the source of the data and the data centers. The computation in fog computing provides fast response times and enables latency sensitive applications. However, industrial systems require time-bounded response times, also denoted as RT. The correctness of such systems depends not only on the logical results of the computations but also on the physical time instant at which these results are produced. Time-bounded responses in fog computing are attributed to two main aspects: computation and communication. In this thesis, we explore both aspects targeting soft RT applications in fog computing in which the usefulness of the produced computational results degrades with real-time requirements violations. With regards to the computation, we provide a systematic literature survey on a novel lightweight RT container-based virtualization that ensures spatial and temporal isolation of co-located applications. Subsequently, we utilize a mechanism enabling RT container-based virtualization and propose a solution for orchestrating RT containers in a distributed environment. Concerning the communication aspect, we propose a solution for a dynamic bandwidth distribution in virtualized networks.

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28

Lee, Young-Jun. "Routing and Efficient Evaluation Techniques for Multi-hop Mobile Wireless Networks." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7455.

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In this dissertation, routing protocols, load-balancing protocols, and efficient evaluation techniques for multi-hop mobile wireless networks are explored. With the advancements made in wireless communication and computer technologies, a new type of mobile wireless network, known as a mobile ad hoc network (MANET), has drawn constant attention. In recent years, several routing protocols for MANETs have been proposed. However, there still remains the need for mechanisms for better scalability support with respect to network size, traffic volume, and mobility. To address this issue, a new method for multi-hop routing in MANETs called Dynamic NIx-Vector Routing (DNVR) is proposed. DNVR has several distinct features compared to other existing on-demand routing protocols, which lead to more stable routes and better scalability. Currently, ad hoc routing protocols lack load-balancing capabilities. Therefore they often fail to provide good service quality, especially in the presence of a large volume of network traffic since the network load concentrates on some nodes, resulting in a highly congested environment. To address this issue, a novel load-balancing technique for ad hoc on-demand routing protocols is proposed. The new method is simple but very effective in achieving load balance and congestion alleviation. In addition, it operates in a completely distributed fashion. To evaluate and verify wireless network protocols effectively, especially to test their scalability properties, scalable and efficient network simulation methods are required. Usually simulation of such large-scale wireless networks needs a long execution time and requires a large amount of computing resources such as powerful CPUs and memory. Traditionally, to cope with this problem, parallel network simulation techniques with parallel computing capabilities have been considered. This dissertation explores a different type of method, which is efficient and can be achieved with a sequential simulation, as well as a parallel and distributed technique for large-scale mobile wireless networks.

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29

Hascoët, Julien. "Contributions to Software Runtime for Clustered Manycores Applied to Embedded and High-Performance Applications." Thesis, Rennes, INSA, 2018. http://www.theses.fr/2018ISAR0029/document.

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Le besoin en calculs est toujours plus important et difficile à satisfaire, spécialement dans le domaine de l’informatique embarquée qui inclue les voitures autonomes, drones et téléphones intelligents. Les systèmes embarqués doivent respecter des contraintes fortes de temps, de consommation et de sécurité. Les nouveaux processeurs parallèles et hétérogènes comme le MPPA® de Kalray utilisé dans cette thèse, doivent alors combiner haute performance et basse consommation. Pour cela, le MPPA® intègre 288 coeurs, regroupés en 18 clusters à mémoire locale partagée, un réseau sur puce et des moteurs DMA pour les communications. Ces processeurs sont difficiles à programmer, engendrant des coûts de développement importants. Cette thèse a pour objectif de simplifier leur programmation tout en optimisant les performances finales. Nous proposons pour cela AOS, une librairie de communication et synchronisation haute performance gérant les mémoires locales distribuées des processeurs clustérisés. La librairie atteint 70% de la crête matérielle pour des transferts supérieurs à 8 KB. Nous proposons plusieurs outils de développement basés sur AOS et des modèles de programmation flux-dedonnées pour accélérer le développement d’applications parallèles pour processeurs clustérisés, notamment OpenVX qui est un nouveau standard pour les applications de vision et les réseaux de neurones. Nous automatisons l’optimisation de l’application OpenVX en faisant du pré-chargement de données et en les fusionnants, pour éviter le mur de la bande passante mémoire externe. Les résultats montrent des facteurs d’accélération super linéaires
The growing need for computing is more and more challenging, especially in the embedded system world with autonomous cars, drones, and smartphones. New highly parallel and heterogeneous processors emerge to answer this challenge. They operate in constrained environments with real-time requirements, reduced power consumption, and safety. Programming these new chips is a time-consuming and challenging task leading to huge software development costs. The Kalray MPPA® processor is a competitive example for low-power super-computing on a single chip. It integrates up to 288 VLIW cores grouped in 18 clusters, each fitted with shared local memory. These clusters are interconnected with a high-bandwidth network-on-chip, and DMA engines are used to communicate. This processor is used in this thesis for experimental results. We propose the AOS library enabling highperformance communications and synchronizations of distributed local memories on clustered manycores. AOS provides 70% of the peak hardware throughput for transfers larger than 8 KB. We propose tools for the implementation of static and dynamic dataflow programs based on AOS to accelerate the parallel application developments onto clustered manycores. We propose an implementation of OpenVX for clustered manycores on top of AOS. OpenVX is a standard based on dataflow for the development of computer vision and neural network computing. The proposed OpenVX implementation includes automatic optimizations like data prefetch to overlap communications and computations, or kernel fusion to avoid the main memory bandwidth bottleneck. Results show super-linear speedups

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30

Meskine, Mohamed. "Vehicular Fog/Edge Computing to improve dependability and performance." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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We have more and more objects connected to the network. These objects need local information increasingly. This means that cloud computing is not suitable in some applications. This is also due to the high latency that it presents. The thesis is focused on the vehicular field. In the presented appli- cation, we will use fog computing and 5G. These two technologies are important to guarantee a good performance. This is important because thanks to that we can avoid an accident. The application is to provide that the user will be able to see the vehicles within a radius of 100 meters. The vehicles within this radius will be presented on the display inside the vehicle. Inside the vehicle there will be a processor that sends messages to the driver in case of emergency. In case that the warning remains, there will be automatic braking and/or steering. The idea of the thesis is to improve three aspects: latency, mobility and reliability. Latency has been improved thanks to the idea of uncorrelation. Mobility, i.e. the time it takes to pass control from one small cell to another, has been improved thanks to the interconnection between the fog nodes and the information on the user’s destination. Reliability is improved thanks to the interconnection between layers and besides thanks to the use of two links.

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31

Bhal, Siddharth. "Fog computing for robotics system with adaptive task allocation." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78723.

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The evolution of cloud computing has finally started to affect robotics. Indeed, there have been several real-time cloud applications making their way into robotics as of late. Inherent benefits of cloud robotics include providing virtually infinite computational power and enabling collaboration of a multitude of connected devices. However, its drawbacks include higher latency and overall higher energy consumption. Moreover, local devices in proximity incur higher latency when communicating among themselves via the cloud. At the same time, the cloud is a single point of failure in the network. Fog Computing is an extension of the cloud computing paradigm providing data, compute, storage and application services to end-users on a so-called edge layer. Distinguishing characteristics are its support for mobility and dense geographical distribution. We propose to study the implications of applying fog computing concepts in robotics by developing a middle-ware solution for Robotic Fog Computing Cluster solution for enabling adaptive distributed computation in heterogeneous multi-robot systems interacting with the Internet of Things (IoT). The developed middle-ware has a modular plug-in architecture based on micro-services and facilitates communication of IOT devices with the multi-robot systems. In addition, the developed middle-ware solutions support different load balancing or task allocation algorithms. In particular, we establish that we can enhance the performance of distributed system by decreasing overall system latency by using already established multi-criteria decision-making algorithms like TOPSIS and TODIM with naive Q-learning and with Neural Network based Q-learning.
Master of Science

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32

POLTRONIERI, Filippo. "Value-of-Information Middlewares for Fog and Edge Computing." Doctoral thesis, Università degli studi di Ferrara, 2021. http://hdl.handle.net/11392/2488252.

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Fog and Edge Computing aim to deliver low-latency, immersive, and powerful services by processing information close to both devices and users. This is well suited for IoT applications in Smart City, where IoT gateways, Cloudlets, Base Stations, and other computational nodes can process (part of) the data generated by the multitude of IoT sensors directly at the edge of the network. However, the implementation of Fog and Edge Computing is challenging because it requires to deal with a (limited number of) constrained devices, dynamic services' requirements, and heterogeneous network conditions. Differently from the Cloud, where computational resources are supposed to be unlimited, Fog and Edge services should be capable to adapt to scarce and constrained resources and deal with the deluge of IoT data. To facilitate the adoption of Fog and Edge Computing this thesis proposes innovative middlewares capable of providing comprehensive solutions to address the highly dynamic characteristics of these environments. These middlewares provide functions to allocate and distribute Fog and Edge services among the available computational devices, monitor the status of the environment, and promptly modify their configuration. To deal with the IoT data deluge this thesis investigates the interesting criterion of Value-of-Information (VoI). Originally born as an extension of Shannon's Information Theory for decision making science, researchers have studied VoI as an information management tool to select and prioritize information processing and dissemination. For this purpose, this thesis proposes the adoption of information management policies allowing the definition of service components, composable software modules that can be chained to create larger and more complex services. In addition, the middlewares presented in this thesis leverage the promising concept of VoI to select only the most valuable piece of information for processing and dissemination and to scale computational workload in an automated and lossiness fashion. This would enable to reduce the computational and network load and to propose innovative methodologies to optimize the available resources. The research efforts presented in this thesis are the results of the collaboration with international institutes and a research period at the Florida Institute for Human and Machine Cognition (IHMC), FL, USA.
Con i termini Fog ed Edge Computing si indicano dei paradigmi computazionali che, spostando l'elaborazione dei dati IoT nelle prossimità sia dei dispositivi che degli utenti, mirano a fornire servizi a bassa latenza, immersivi e real-time. Fog ed Edge Computing trovano applicazione in contesti Smart Cities, dove è possibile sfruttare la capacità computazionale di gateway IoT, Cloudlet e Base Station per elaborare parte dei dati generati dall'IoT direttamente ai margini della rete. L'adozione dei paradigmi di Fog ed Edge Computing è tuttavia complessa in quanto pone una serie di sfide tra cui il processamento dell’enorme mole di dati generati dall’IoT, la presenza di un numero limitato di dispositivi altamente eterogenei e con capacità computazionali scarse, requisiti di servizio altamente dinamici e reti con caratteristiche eterogenee. Per garantire i requisiti stringenti di bassa latenza, soluzioni per Fog ed Edge Computing devono essere in grado di utilizzare al meglio le scarse risorse a disposizione, gestendole al meglio. Se questi paradigmi sono oggetto di ampie ricerche, vi è la necessità di investigare soluzioni innovative che consentano di gestire l’enorme mole dati IoT e permettere una concreta applicazione di Fog ed Edge Computing. Questa tesi propone middleware innovativi in grado di fornire soluzioni complete per fronteggiare al meglio le caratteristiche altamente dinamiche di scenari Smart Cities, fornendo metodologie e strumenti per allocare e distribuire servizi tra le risorse a disposizione, monitorare lo stato delle risorse e modificare prontamente la loro configurazione. Come criterio innovativo per la prioritizzazione dei dati IoT per processamento e disseminazione, questa tesi adotta il concetto di Value-of-Information (VoI), nato come estensione della Teoria dell'Informazione di Shannon e applicato in ambiti decisionali. A tal fine, questa tesi propone politiche di gestione delle informazioni che consentono di realizzare servizi modulari e facilmente (ri-)componibili e tecniche di ottimizzazione innovative che ben si adattano a questi servizi. Inoltre, i middleware presentati in questa tesi integrano il concetto di VoI sia a livello di servizio che a livello di gestione per selezionare le informazioni più preziose per l'elaborazione e la diffusione, riducendo così il carico computazionale e garantendo una gestione ottimale dei dispositivi e della rete. Le ricerche presentate in questa tesi sono il risultato della collaborazione con istituti di ricerca internazionali e di un periodo di ricerca trascorso presso il Florida Institute for Human and Machine Cognition (IHMC), FL, USA.

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Holm, Rasmus. "The fog-unit : Evaluation of the fog-unit’s effect on network performance." Thesis, Mittuniversitetet, Avdelningen för informationssystem och -teknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-34048.

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Today at various locations and factories we have a lot of sensors and actuators that interact with each other and a control-unit. The control-unit is in most cases a cloud-based solution. This is in most cases a good solution. However, there is a rise in expected devices and sensors which will most likely be too much data for the existing network to handle. This paper researches if a fog-unit might be the solution to this problem. The setup of the fog-unit in the network is a unit between the cloud and the sensors and actuators. In this paper the fog-unit and sensors/actuators have been emulated on Raspberry Pi’s. The sensors are emulated using python-threads and communicate with the fog-unit using the UDP-based protocol CoAP and the fog communicates to the cloud using the TCP- based protocol MQTT. After a prototype was built it using said Raspberry Pi’s it was sent through a few measurements in the fields of bandwidth, cloud-utilization and response times. This was later compared to another setup without the fog-unit as the control setup. The result with this kind of setup was that a fog-unit lowers the cloud-utilization and use of bandwidth, however it increases the round trip time of a request from the cloud by a large amount. Which leads to the conclusion that a fog-unit in this kind of setup might be a good network solution if the response time to the cloud isn’t important.

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Ahmed, Arif. "Efficient cloud application deployment in distributed fog infrastructures." Thesis, Rennes 1, 2020. http://www.theses.fr/2020REN1S004.

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Les architectures Fog computing sont composées d'un grand nombre de machines dispersées dans une zone géographique telle qu'une ville ou une région. Dans ce contexte il est important de permettre un démarrage rapide des applications déployées sous forme de containers Docker. Cette thèse étudie les raisons de la lenteur de déploiement, et identifie trois opportunités susceptibles de réduire le temps de déploiement des conteneurs: (1) améliorer le taux de réussite du cache Docker; (2) accélérer l'opération d'installation d'une image; et (3) accélérer le processus de démarrage après la création d'un conteneur
Fog computing architectures are composed of a large number of machines distributed across a geographical area such as a city or a region. In this context it is important to support a quick startup of applications deployed in the for of docker containers. This thesis explores the reasons for slow deployment and identifies three improvement opportunities: (1) improving the Docker cache hit rate; (2) speed-up the image installation operation; and (3) accelerate the application boot phase after the creation of a container

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35

Khan, Kafeel Ahmed. "Web-based Management of Fog Computing Services implemented in Docker." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18934/.

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The aim and motivation of this thesis project is to introduce the implementation of the Fog computing scenario. For possible demonstration, we use the feasible or concur solution already deployed in the cloud computing paradigm. An emerging trend of IoT in the current era required more development in cloud computing due to the centralized control of resources that is no-more beneficial in the IoT base scenario. A distributed base approach called Fog computing is introduced that manages the services without being the use of a centralized pool of cloud. Although, Fog cannot fully function without being centralized control. But in order to implement the Fog node, I used a hypervisor supported device to configure virtual machines on the server and considered it as edge or fog node and make it capable to hold Fog services. Further, I used the docker container orchestration tool configure along with the Apache server that can host webpages to interact with the Docker API support and last a local machine that is used to access the fog node by a browser. Further, I analyze the response time of on-demand service with respect to the number of containers and conclude that using Fog as an intermittent node reduces the overall container formation time as compared to those users that directly connect with the cloud server this approach can fulfill some level of latency requirement by IoT devices.

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36

Fahs, Ali Jawad. "Proximity-aware replicas management in geo-distributed fog computing platforms." Thesis, Rennes 1, 2020. http://www.theses.fr/2020REN1S076.

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L'architecture géo-distribuée de fog computing fournit aux utilisateurs des ressources accessibles avec une faible latence. Cependant, exploiter pleinement cette architecture nécessite une distribution similaire de l'application par l'utilisation de techniques de réplication. Par conséquent, la gestion de ces répliques doit intégrer des algorithmes prenant en compte la proximité aux différents niveaux de gestion des ressources du système. Dans cette thèse, nous avons abordé ce problème à travers trois contributions. Premièrement, nous avons conçu un système de routage des requêtes entre les utilisateurs et les ressource prenant en compte la proximité. Deuxièmement, nous avons proposé des algorithmes dynamiques pour le placement des répliques prenant en compte les derniers percentiles de la latence. Enfin, nous avons développé un système de mise à l’échelle automatique qui ajustent le nombre des répliques de l'application en fonction de la charge subie par les applications fog computing
Geo-distributed fog computing architectures provide users with resources reachable within low latency. However, fully exploiting the fog architecture requires a similar distribution of the application by the means of replication. As a result, fog application replica management should implement proximity-aware algorithms to handle different levels of resource management. In this thesis, we addressed this problem over three contributions. First, we designed a proximity-aware user-to-replica routing mechanism. Second, we proposed dynamic tail-latency-aware replica placement algorithms. Finally, we developed autoscaling algorithms to dynamically scale the application resources according to the non-stationary workload experienced by fog platforms

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Jalew, Esubalew Alemneh. "Fog Computing based traffic Safety for Connected Vulnerable Road Users." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCK057/document.

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Chaque année, des millions de personnes meurent et beaucoup d'autres subissent des séquelles graves à la suite d'accidents de la route. Malgré une multitude d’initiatives, le nombre de cas mortels et d'accidents graves augmente chaque année en engendrant des problèmes préoccupants à la fois sociaux, économiques et sanitaires. En raison de leur nombre élevé et de l'absence de protection personnelle, plus de la moitié de ces décès concerne les usagers vulnérables (en anglais, vulnerable road users - VRU) regroupant les piétons, cyclistes et motocyclistes. Les appareils mobiles, combinés à la technologie de Fog Computing (ou informatique géodistribuée, ou même informatique en brouillard), représentent une solution réaliste à court terme pour les protéger en les avertissant de l’imminence d'un accident de circulation. L’omniprésence des appareils mobiles et leurs capacités de calcul élevées font de ces appareils un élément important à considérer dans les solutions de sécurité routière. Le Fog Computing offre des fonctionnalités adaptées aux applications de sécurité routière, puisqu’il s’agit d’une extension du Cloud Computing permettant de rapprocher les services informatiques, le stockage et le réseau au plus près des utilisateurs finaux. Par conséquent, dans cette thèse, nous proposons une architecture réseau sans infrastructure supplémentaire (PV-Alert) pour des fins de sécurité routière et reposant uniquement sur les appareils mobiles des VRU et des conducteurs sur la route avec l’aide du concept de Fog Computing. Les données géographiques et cinématiques de ces appareils sont collectées et envoyées périodiquement au serveur fog situé à proximité. Le serveur fog traite ces données en exécutant un algorithme de calcul de risque d’accident de circulation et renvoie des notifications en cas d'accident imminent. L’évaluation de cette architecture montre qu’elle est capable de générer des alertes en temps réel et qu’elle est plus performante que d’autres architectures en termes de fiabilité, d’évolutivité et de latence
Annually, millions of people die and many more sustain non-fatal injuries because of road traffic crashes. Despite multitude of countermeasures, the number of causalities and disabilities owing to traffic accidents are increasing each year causing grinding social, economic, and health problems. Due to their high volume and lack of protective-shells, more than half of road traffic deaths are imputed to vulnerable road users (VRUs): pedestrians, cyclists and motorcyclists. Mobile devices combined with fog computing can provide feasible solutions to protect VRUs by predicting collusions and warning users of an imminent traffic accident. Mobile devices’ ubiquity and high computational capabilities make the devices an important components of traffic safety solutions. Fog computing has features that suits to traffic safety applications as it is an extension of cloud computing that brings down computing, storage, and network services to the proximity of end user. Therefore, in this thesis, we have proposed an infrastructure-less traffic safety architecture that depends on fog computing and mobile devices possessed by VRUs and drivers. The main duties of mobile devices are extracting their positions and other related data and sending cooperative awareness message to a nearby fog server using wireless connection. The fog server estimates collision using a collision prediction algorithm and sends an alert message, if an about-to-occur collision is predicted. Evaluation results shows that the proposed architecture is able to render alerts in real time. Moreover, analytical and performance evaluations depict that the architecture outperforms other related road safety architectures in terms of reliability, scalability and latency. However, before deploying the architecture, challenges pertaining to weaknesses of important ingredients of the architecture should be treated prudently. Position read by mobile devices are not accurate and do not meet maximum position sampling rates traffic safety applications demand. Moreover, continuous and high rate position sampling drains mobile devices battery quickly. From fog computing’s point of view, it confronts new privacy and security challenges in addition to those assumed from cloud computing. For aforementioned challenges, we have proposed new solutions: (i) In order to improve GPS accuracy, we have proposed an efficient and effective two-stage map matching algorithm. In the first stage, GPS readings obtained from smartphones are passed through Kalman filter to smooth outlier readings. In the second stage, the smoothed positions are mapped to road segments using online time warping algorithm. (ii) position sampling frequency requirement is fulfilled by an energy efficient location prediction system that fuses GPS and inertial sensors’ data. (iii) For energy efficiency, we proposed an energy efficient fuzzy logic-based adaptive beaconing rate management that ensures safety of VRUs. (iv) finally, privacy and security issues are addressed indirectly using trust management system. The two-way subjective logic-based trust management system enables fog clients to evaluate the trust level of fog servers before awarding the service and allows the servers to check out the trustworthiness of the service demanders. Engaging omnipresent mobile device and QoS-aware fog computing paradigm in active traffic safety applications has the potential to reduce overwhelming number of traffic accidents on VRUs

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38

Rosu, Marcel-Catalin. "Communication support for cluster computing." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/8256.

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39

Shirin, Abkenar Forough. "Towards Hyper-efficient IoT Networks Using Fog Paradigm." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/28951.

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Fog computing was emerged as a treasured paradigm to improve the efficiency of the typical cloud of things (CoT) architecture of the Internet of Things (IoT) networks. Contrasting to the CoT in which the resource-rich high-performance data centers (DCs) are located far from the energy-constrained terminal nodes (TNs), fog nodes (FNs) in fog-enabled architecture provide computing resources in the proximity of the TNs. Therefore, the TNs consume less energy to offload their generated tasks to the FNs rather than the cloud DCs. Moreover, shortening the distance between the TNs and the FNs results in alleviating the transmission latency for the delay-sensitive tasks generated by the TNs. This is more significant for specific applications, such as smart healthcare, search and rescue, and disaster management, wherein making a prompt decision is vital to save lives. However, Fog-IoT networks still suffer from challenges regarding energy efficiency and provisioning quality of service (QoS) requirements, especially in terms of delay and throughput. The motivation behind this thesis is to tackle the corresponding challenges and improve the performance of the Fog-IoT networks. To this end, novel optimization problems, models, methods, and algorithms are proposed that mainly focus on the energy efficiency improvement and QoS provisioning in Fog-IoT networks. Moreover, due to the importance of the mobility of FNs, the contributions of the thesis encompass improving the performance of Fog-IoT networks with respect to both fixed and mobile FNs.

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Zaripov, Behruz. "Analysis of Fog Networking Procedures in Heterogeneous Wireless Networks." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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The purpose of this study is to provide a general framework of the latest trends of mobile network architectures. The two main architectures treated in this work are Cloud-RAN and Fog-RAN. We give descriptions of both architectures, then show advantages and disadvantages of them. We mainly focus on the performance of Fog-RAN model taking into account only computation and communication latencies. In order to analyse our Fog-RAN architecture, we measure the impact of traffic produced in our network, by using 3 different policies: Random Policy, Maximum Available Capacity Policy and Nearest Node Policy. Furthermore, we measure the impact of delay by fixing the amount of traffic generated by the network. Numerical results of our considered scenarios show that the maximum available capacity policy outperforms two other polices, when the traffic produced in the network is very high. When the traffic is very low, the best policy is the nearest node one. On the other hand, by fixing the amount of traffic we show that when the delay threshold is from 1-3 ms the Maximum capacity policy performs better than two other policies. When the delay threshold is greater than 5 ms the Nearest Node policy shows better results.

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41

Subbiah, Arun. "Design and evaluation of a distributed diagnosis algorithm for arbitrary network topologies in dynamic fault environments." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/13273.

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42

Ahlcrona, Felix. "Sakernas Internet : En studie om vehicular fog computing påverkan i trafiken." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-15713.

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Framtidens fordon kommer vara väldigt annorlunda jämfört med dagens fordon. Stor del av förändringen kommer ske med hjälp av IoT. Världen kommer bli oerhört uppkopplat, sensorer kommer kunna ta fram data som de flesta av oss inte ens visste fanns. Mer data betyder även mer problem. Enorma mängder data kommer genereras och distribueras av framtidens IoT-enheter och denna data behöver analyseras och lagras på effektiva sätt med hjälp av Big data principer. Fog computing är en utveckling av Cloud tekniken som föreslås som en lösning på många av de problem IoT lider utav. Är tradionella lagringsmöjligheter och analyseringsverktyg tillräckliga för den enorma volymen data som kommer produceras eller krävs det nya tekniker för att stödja utvecklingen? Denna studie kommer försöka besvara frågeställningen: ”Vilka problem och möjligheter får utvecklingen av Fog computing i personbilar för konsumenter?” Frågeställningen besvaras genom en systematisk litteraturstudie. Den systematiska litteraturstudien syfte är identifiera och tolka tidigare litteratur och forskning. Analys av materialet har skett med hjälp av öppen kodning som har använts för att sortera och kategorisera data. Resultat visar att tekniker som IoT, Big data och Fog computing är väldigt integrerade i varandra. I framtidens fordon kommer det finns mycket IoTenheter som producerar enorma mängder data. Fog computing kommer bli en effektiv lösning för att hantera de mängder data från IoT-enheterna med låg fördröjning. Möjligheterna blir nya applikationer och system som hjälper till med att förbättra säkerheten i trafiken, miljön och information om bilens tillstånd. Det finns flera risker och problem som behöver lösas innan en fullskalig version kan börja användas, risker som autentisering av data, integriteten för användaren samt bestämma vilken mobilitetsmodell som är effektivast.
Future vehicles will be very different from today's vehicles. Much of the change will be done using the IoT. The world will be very connected, sensors will be able to access data that most of us did not even know existed. More data also means more problems. Enormous amounts of data will be generated and distributed by the future's IoT devices, and this data needs to be analyzed and stored efficiently using Big data Principles. Fog computing is a development of Cloud technology that is suggested as a solution to many of the problems IoT suffer from. Are traditional storage and analysis tools sufficient for the huge volume of data that will be produced or are new technologies needed to support development? This study will try to answer the question: "What problems and opportunities does the development of Fog computing in passenger cars have for consumers?" The question is answered by a systematic literature study. The objective of the systematic literature study is to identify and interpret previous literature and research. Analysis of the material has been done by using open coding where coding has been used to sort and categorize data. Results show that technologies like IoT, Big data and Fog computing are very integrated in each other. In the future vehicles there will be a lot of IoT devices that produce huge amounts of data. Fog computing will be an effective solution for managing the amount of data from IoT devices with a low latency. The possibilities will create new applications and systems that help improve traffic safety, the environment and information about the car's state and condition. There are several risks and problems that need to be resolved before a full-scale version can be used, such as data authentication, user integrity, and deciding on the most efficient mobility model.

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Ramalho, Fl?vio de Sousa. "SmartEdge: fog computing cloud extensions to support latency-sensitive IoT applications." PROGRAMA DE P?S-GRADUA??O EM SISTEMAS E COMPUTA??O, 2016. https://repositorio.ufrn.br/jspui/handle/123456789/22557.

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O r?pido crescimento do n?mero de dispositivos conectados ? Internet, associado ?s taxas crescentes de popularidade e demanda de aplica??es e servi?os em tempo real na nuvem, com restri??es de lat?ncia, torna muito dif?cil para estruturas de computa??o em nuvem tradicionais acomod?-los de forma eficiente. Mais especificamente, a abordagem centralizada adotada tradicionalmente por Data Centers (DC) atuais apresentam problemas de desempenho para atender de aplica??es em nuvem com alta densidade, principalmente quanto a capacidade de resposta e escalabilidade. Nossa depend?ncia insubstitu?vel por computa??o em nuvem, exige infra-estruturas de DCs sempre dispon?veis, enquanto mant?m ao mesmo tempo capacidades de desempenho suficientes para responder a uma enorme quantidade de solicita??es de aplicativos em nuvem. Neste trabalho, a aplicabilidade do emergente paradigma de computa??o em n?voa ? explorada para melhorar o desempenho no suporte de aplica??es em nuvem sens?veis ? lat?ncia voltadas a Internet das Coisas (do ingl?s Internet of Things - IoT). Com base neste objetivo, apresentamos o novo modelo denominado Infraestrutura de Borda como um Servi?o (do ingl?s Edge Infrastructure as a Service - EIaaS), que procura oferecer um novo modelo de computa??o em nuvem com servi?o de entrega baseado em computa??o de borda voltado a atender de forma eficiente as exig?ncias de aplica??es IoT em tempo real sens?veis ? lat?ncia. Com a abordagem EIaaS, provedores de nuvem podem implantar dinamicamente aplica??es/servi?os IoT diretamente nas infra-estruturas de computa??o de borda, nem como gerir seus recursos de n?vem/rede em tempo de execu??o, como forma de manter as aplica??es IoT sempre melhor conectadas e melhor servidas. A abordagem resultante ? arquitetada em uma estrutura modular, tendo como base tecnol?gica ferramentas de Rede Definida por Software (do ingl?s, Software- Defined Networking - SDN) para lidar com recursos de computa??o de borda (CPU, mem?ria, etc.) e de rede (caminhos, largura de banda, etc.), respectivamente. Os resultados preliminares mostram como as principais t?cnicas de virtualiza??o utilizadas no ?mbito deste trabalho, afetam o desempenho das aplica??es na infraestrutura de borda da rede. A virtualiza??o por containers leva vantagem sobre a t?cnica de virtualiza??o por m?quinas virtuais para implantar aplica??es na borda da rede, uma vez que oferece grande flexibilidade mesmo na presen?a de demanda de recursos.
The rapid growth in the number of Internet-connected devices, associated to the increasing rates in popularity and demand for real-time and latency-constrained cloud application services makes the use of traditional cloud computing frameworks challenging to afford such environment. More specifically, the centralized approach traditionally adopted by current Data Center (DC) pose performance issues to suit a high density of cloud applications, mainly in terms to responsiveness and scalability. Our irreplaceable dependency on cloud computing, demands DC infrastructures always available while keeping, at the same time, enough performance capabilities for responding to a huge amount of cloud application requests. In this work, the applicability of the fog computing emerging paradigm is exploited to enhance the performance on supporting latency-sensitive cloud applications tailored for Internet of Things (IoT).With this goal in mind, we introduce a new service model named Edge Infrastructure as a Service (EIaaS), which seeks to offer a new edge computing tailored cloud computing service delivery model to efficiently suit the requirements of the real-time latency-sensitive IoT applications. With EIaaS approach, cloud providers are allowed to dynamically deploy IoT applications/services in the edge computing infrastructures and manage cloud/network resources at the run time, as means to keep IoT applications always best connected and best served. The resulting approach is modeled in a modular architecture, leveraging both container and Software-Defined Networking technologies to handle edge computing (CPU, memory, etc) and network resources (path, bandwidth, etc) respectively. Preliminary results show how the virtualization technique affects the performance of applications at the network edge infra. The container-based virtualization takes advantage over the hypervisor-based technique for deploying applications at the edge computing infrastructure, as it offers a great deal of flexibility under the presence of resource constraints.

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Lee, Chun-ming, and 李俊明. "Efficient communication subsystem for cluster computing." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31221245.

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45

Lee, Chun-ming. "Efficient communication subsystem for cluster computing /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20604592.

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46

Hill, Ryan Tebbutt. "Adaptive interfaces for mobile preference-based searching." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/1248.

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Today's mobile computing devices provide a convenient means to search for points-of-interest (POIs) such as restaurants and accommodation. Mobile Preference-Based Search Tools (PBSTs) allow users to identify POIs such as restaurants or accommodation most suited to their needs and constraints using a mobile device. These devices however, have several design constraints including limited screen space and hardware capabilities. Adaptive User Interfaces (AUIs) have been proposed to address these issues but have not been extensively applied to mobile PBSTs such as mobile tourist guides. In addition, AUIs possess several benefits and advantages over static (traditional) interfaces, which do not take a user's preferences, skill set and experience into account. Little research, however, has been conducted into identifying the potential benefits of AUIs for mobile preference-based searching (PBS). The aim of this research was to determine the extent to which an AUI could improve the effectiveness and user satisfaction of mobile PBS. A literature study was conducted to determine the benefits and limitations of existing mobile PBSTs and determine how these could be improved. The potential benefits of AUIs for mobile PBSTs and a mobile map-based visualisation system were identified. A suitable model for incorporating an AUI into a mobile PBST was identified. The requirements for a mobile PBST were combined with the potentially adaptable objects of a Mobile Map-based Visualisation (MMV) system to provide adaptation suggestions for POInter, an existing mobile tourist guide. A field study using POInter was conducted in order to measure the extent to which participants agreed with suggestions provided for adapting the information, interaction and visualisation aspects of the system. These results were used to derive adaptation requirements for A-POInter, an adaptive version of POInter. Using a model-based design approach, an AUI was designed and implemented for A-POInter. An extensive field study was then conducted to evaluate the usability of the adaptations provided by A-POInter. The quantitative and qualitative data collected from the evaluations allowed the usability of A-POInter to be determined. The results of the field study showed that the participants were highly satisfied with the usability and the usefulness of the adaptations provided by A-POInter. Conclusions and recommendations for future work based on the results of the research were then outlined to conclude the dissertation.

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47

Bida, Mihail. "Tecniche di Drift Detection basate su Fog Computing per Scenari Industria 4.0." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23020/.

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Uno dei concetti più interessanti di Industria 4.0, quella che oggi viene intesa come quarta rivoluzione industriale, è il Digital Twin (gemello digitale), basato sull'idea che ogni parte fisica debba avere una rappresentazione nel mondo digitale. Questo è permesso dalla grande quantità di dati della sensoristica, automaticamente generati e provenienti dai macchinari industriali. Una sfaccettatura del Digital Twin, che si basa sull'analisi di questi flussi di dati con lo scopo di ottimizzazione dei processi produttivi, è la Predictive Maintenance. Questa, consiste nell’effettuare diagnosi dei componenti e del macchinario tramite lo studio dei datastream in modo da individuare interventi di manutenzione soltanto quando strettamente necessario. Questo studio si focalizza sulla regressione, una tecnica specifica basata sull'apprendimento automatico usato per identificare un concept drift, un cambiamento di concetto nei datastream in entrata, in modo da poter attivare azioni di manutenzione predittiva. L'obiettivo è di riconoscere l'usura crescente che porterebbe il macchinario a un fallimento in modo da prevenirlo, cercando di discriminare tra dati sani di normale utilizzo e segnalare un cambio di concetto quando dati non visti o non sani vengono incontrati. Si è costruita una pipeline composta da varie componenti estendibili e personalizzabili che permettono di scegliere i modelli di regressione da testare (e allenare) e di adattare le parti a stream differenti. Questa gestisce il flusso di dati dal macchinario fino all'analisi e all'eventuale allarme. L'architettura è stata pensata ed è stata fornita una sua reale implementazione su fog node tramite l'utilizzo di docker container. Il tutto è stato testato e ne vengono mostrati i risultati utilizzando dati sintetizzati secondo la letteratura presente per i macchinari industriali.

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48

Bhowmick, Satyajit. "A Fog-based Cloud Paradigm for Time-Sensitive Applications." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1467988828.

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49

Debbage, Mark. "Reliable communication protocols for high-performance computing." Thesis, University of Southampton, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358359.

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50

Tsai, I.-Ming, and 蔡一鳴. "Quantum Boolean Circuits for Quantum Computing and Communications." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/68727984781291695914.

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博士
國立臺灣大學
電機工程學研究所
91
Quantum information science is a multidisciplinary research area. It combines quantum mechanics, theoretical computer science, information theory, and mathematics to explore the possibilities of making efficient computing and communication. In this dissertation, we first present a historical overview of quantum mechanics and give an introduction of quantum computing and quantum communication, and then we propose some important engineering applications of quantum boolean circuits. First, we show how a classical Boolean function can be realized using quantum boolean circuits with minimum space. It is well-known that any classical combinational circuits can be implemented with Toffoli gates using the straightforward, but inefficient, replacement algorithm. In this dissertation, we propose a systematic procedure to derive a minimum space quantum circuit to implement a given classical combinational logic. Second, we explain how quantum boolean circuits can be used to search multiple targets in an unordered database. To do this, we show how quantum boolean circuits can be used to implement the oracle circuit and the inversion-about-average function in Grover's search algorithm. In addition, we also show that a slight modification of the oracle circuit can be used to search multiple targets. Finally, we present a switching architecture such that digital data can be switched in the quantum domain. This results in a quantum switch that can be used to build classical and quantum information networks. Compared with a traditional space or time domain switch, the proposed switching mechanism is much more scalable. Assuming an n-by-n quantum switch, the space consumption grows linearly, i.e. O(n), while the time complexity is O(1) for unicasting, and O(log n) for multicasting. Based on these advantages, a high throughput switching device can be built simply by increasing the number of I/O ports.

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