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1
Alexander, David. „A Network Metadata Infrastructure for Locating Network Devices“. Ohio University / OhioLINK, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1088176648.
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Kühnert, Wolfram. „Dynamic Devices Network Architecture“. [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10952962.
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3
Zenteno, Efrain. „Vector Measurements for Wireless Network Devices“. Licentiate thesis, KTH, Signalbehandling, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-111863.
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Wireless networks are an iconic technology of today’s modern era, theyare present in our daily activities as can be exemplified by cellular communications,wi-fi, bluetooth, and others. Vector measurements play an importantrole in the design, simulation, and testing of wireless networks and are usedto characterize key devices operating in the radio interface, such as amplifiers,filters, and mixers.Accurate characterization is the key for improving the capacity and efficiencyof wireless networks. As the demand for network capacity continuouslyincreases, the accuracy of vector measurements must also improve. Further,it is anticipated that such trends will continue in the years to come. Consequently,the wireless industry needs to include nonlinear behavior in theircharacterization and analysis, to assess and guaranty the operation of the devices,and to comply to the specifications from governmental regulations. Incontrast to linear behavior, nonlinear behavior presents an additional bandwidthrequirement because the signal bandwidth grows when it passes throughnonlinear devices. In this thesis, vector measurements for devices operatingin wireless networks are studied, emphasizing a synthetic approach for theinstrumentation. This approach enables the use of digital post-processing algorithms,which enhances the measurement accuracy and/or speed and canovercome hardware impairments. This thesis presents the design of a vectorialmeasurement system for wireless devices considering the aforementionedtrends and requirements. It also explores the advantages of the proposedapproach, describes its limitations, and discusses the digital signal processingalgorithms used to reach its final functionality. Finally, measurement resultsof the proposed setup are presented, analyzed and compared to those of modernindustrial instruments.QC 20130204
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Duan, Xiao. „DSP-enabled reconfigurable optical network devices and architectures for cloud access networks“. Thesis, Bangor University, 2018. https://research.bangor.ac.uk/portal/en/theses/dspenabled-reconfigurable-optical-network-devices-and-architectures-for-cloud-access-networks(68eaa57e-f0af-4c67-b1cf-c32cfd2ee00f).html.
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To meet the ever-increasing bandwidth requirements, the rapid growth in highly dynamic traffic patterns, and the increasing complexity in network operation, whilst providing high power consumption efficiency and cost-effectiveness, the approach of combining traditional optical access networks, metropolitan area networks and 4-th generation (4G)/5-th generation (5G) mobile front-haul/back-haul networks into unified cloud access networks (CANs) is one of the most preferred “future-proof” technical strategies. The aim of this dissertation research is to extensively explore, both numerically and experimentally, the technical feasibility of utilising digital signal processing (DSP) to achieve key fundamental elements of CANs from device level to network architecture level including: i) software reconfigurable optical transceivers, ii) DSP-enabled reconfigurable optical add/drop multiplexers (ROADMs), iii) network operation characteristics-transparent digital filter multiple access (DFMA) techniques, and iv) DFMA-based passive optical network (PON) with DSP-enabled software reconfigurability. As reconfigurable optical transceivers constitute fundamental building blocks of the CAN’s physical layer, digital orthogonal filtering-based novel software reconfigurable transceivers are proposed and experimentally and numerically explored, for the first time. By making use of Hilbert-pair-based 32-tap digital orthogonal filters implemented in field programmable gate arrays (FPGAs), a 2GS/s@8-bit digital-to-analogue converter (DAC)/analogue-to-digital converter (ADC), and an electro-absorption modulated laser (EML) intensity modulator (IM), world-first reconfigurable real-time transceivers are successfully experimentally demonstrated in a 25km IMDD SSMF system. The transceiver dynamically multiplexes two orthogonal frequency division multiplexed (OFDM) channels with a total capacity of 3.44Gb/s. Experimental results also indicate that the transceiver performance is fully transparent to various subcarrier modulation formats of up to 64-QAM, and that the maximum achievable transceiver performance is mainly limited by the cross-talk effect between two spectrally-overlapped orthogonal channels, which can, however, be minimised by adaptive modulation of the OFDM signals. For further transceiver optimisations, the impacts of major transceiver design parameters including digital filter tap number and subcarrier modulation format on the transmission performance are also numerically explored. II Reconfigurable optical add/drop multiplexers (ROADMs) are also vital networking devices for application in CANs as they play a critical role in offering fast and flexible network reconfiguration. A new optical-electrical-optical (O-E-O) conversion-free, software-switched flexible ROADM is extensively explored, which is capable of providing dynamic add/drop operations at wavelength, sub-wavelength and orthogonal sub-band levels in software defined networks incorporating the reconfigurable transceivers. Firstly, the basic add and drop operations of the proposed ROADMs are theoretically explored and the ROADM designs are optimised. To crucially validate the practical feasibility of the ROADMs, ROADMs are experimentally demonstrated, for the first time. Experimental results show that the add and drop operation performances are independent of the sub-band signal spectral location and add/drop power penalties are < 2dB. In addition, the ROADMs are also robust against a differential optical power dynamic range of > 2dB and a drop RF signal power range of 7.1dB. In addition to exploring key optical networking devices for CANs, the first ever DFMA PON experimental demonstrations are also conducted, by using two real-time, reconfigurable, OOFDM-modulated optical network units (ONUs) operating on spectrally overlapped multi-Gb/s orthogonal channels, and an offline optical line terminal (OLT). For multipoint-to-point upstream signal transmission over 26km SSMF in an IMDD DFMA PON, experiments show that each ONU achieves a similar upstream BER performance, excellent robustness to inter-ONU sample timing offset (STO) and a large ONU launch power variation range. Given the importance of IMDD DFMA-PON channel frequency response roll-off, both theoretical and experimental explorations are undertaken to investigate the impact of channel frequency response roll-off on the upstream transmission of the DFMA PON system Such work provides valuable insights into channel roll-off-induced performance dependencies to facilitate cost-effective practical network/transceiver/component designs.
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Cardwell, Gregory S. „Residual network data structures in Android devices“. Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5506.
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Approved for public release; distribution is unlimitedThe emergence and recent ubiquity of Smartphones present new opportunities and challenges to forensic examiners. Smartphones enable new mobile application and use paradigms by being constantly attached to the Internet via one of several physical communication media, e.g. cellular radio, WiFi, or Bluetooth. The Smartphone's storage medium represents a potential source of current and historical network metadata and records of prior data transfers. By using known ground truth data exchanges in a controlled experimental environment, this thesis identifies network metadata stored by the Android operating system that can be readily retrieved from the device's internal non-volatile storage. The identified network metadata can ascertain the identity of prior network access points to which the device associated. An important by-product of this research is a well-labeled Android Smartphone image corpus, allowing the mobile forensic community to perform repeatable, scientific experiments, and to test mobile forensic tools.
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Anderson, Pehr C. (Pehr Christian) 1974. „Filaments : lightweight network interfaces for embedded devices“. Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/46249.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Includes bibliographical references (leaf 63).
Filaments are low-cost interfaces for attaching devices to an Ethernet network. While most networking research pushes for faster high-end systems, the filament project targets low-end devices with the goal of making networking easy. Filaments wrap the complexity of the network into a simple and convenient package. The vast majority of device communications require only a tiny thread or filament of connectivity. Before filaments, one could either tie each device to a desktop PC or to deploy a specialized device network. Filaments allow you to leverage the same network used by desktop computers without making devices dependent on them.
by Pehr C. Anderson.
M.Eng.
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Tan, SiewYeen Agnes. „A Network Measurement Tool for Handheld Devices“. Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/32982.
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This thesis describes a performance measurement tool that allows a user to measure network performance using a handheld device. The measurement tool consists of a client program that runs on a Microsoft Pocket PC device and a server program that runs on a regular Microsoft Windows computer. Both programs are Windows applications implemented in C/C++ using the Microsoft Embedded Visual Tool and Microsoft Visual Studio. The use of a Pocket PC device provides mobility to users, which can save time and energy when performing experiments. The thesis describes the design of the performance measurement application, implementation issues, and tests conducted using the tool.Master of Science
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Yusuf, Adewale, Jerry Lartey und Vilhelm Wareus. „Network Admission Control (NAC)Securing end point devices“. Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-5507.
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There have been remarkable growths in wireless communication networks in
recent years; this is because of its merits over the wired networks such as
Mobility and convenience. Wireless networks transmit the signal over the
open air via radio waves of different frequencies, this makes it to be
vulnerable to several attacks and anybody on the street can easily intercept the
wireless data or inject new data into the entire network. There has been
existence of wired equivalent privacy (WEP) protocol (IEEE 802.11i), which
was designed for wireless network security. There were concerns of security
vulnerabilities in WEP; this made it necessary for the implementation of
another solution to overcome the weaknesses of the previous wireless
network security. The IEEE 802.1X (port-based network admission control)
which is defined on Extensible Authentication protocol (EAP) provides
effective and efficient admission control to wireless and other networks
devices [8].
Our thesis investigates the efficiency of NAC (IEEE 802.1X) as a security
solution, access different vendor solutions, protocols supported and look into
the inter-operability of these various vendors. In as much as we support the
premise of NAC being an excellent solution, we will also make brilliant
recommendations in this thesis to be considered for future refinements of this
security solution as well as deployment scenarios for the university network.
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Spadavecchia, Ljiljana. „A network-based asynchronous architecture for cryptographic devices“. Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/860.
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The traditional model of cryptography examines the security of the cipher as a mathematical function. However, ciphers that are secure when specified as mathematical functions are not necessarily secure in real-world implementations. The physical implementations of ciphers can be extremely difficult to control and often leak socalled side-channel information. Side-channel cryptanalysis attacks have shown to be especially effective as a practical means for attacking implementations of cryptographic algorithms on simple hardware platforms, such as smart-cards. Adversaries can obtain sensitive information from side-channels, such as the timing of operations, power consumption and electromagnetic emissions. Some of the attack techniques require surprisingly little side-channel information to break some of the best known ciphers. In constrained devices, such as smart-cards, straightforward implementations of cryptographic algorithms can be broken with minimal work. Preventing these attacks has become an active and a challenging area of research. Power analysis is a successful cryptanalytic technique that extracts secret information from cryptographic devices by analysing the power consumed during their operation. A particularly dangerous class of power analysis, differential power analysis (DPA), relies on the correlation of power consumption measurements. It has been proposed that adding non-determinism to the execution of the cryptographic device would reduce the danger of these attacks. It has also been demonstrated that asynchronous logic has advantages for security-sensitive applications. This thesis investigates the security and performance advantages of using a network-based asynchronous architecture, in which the functional units of the datapath form a network. Non-deterministic execution is achieved by exploiting concurrent execution of instructions both with and without data-dependencies; and by forwarding register values between instructions with data-dependencies using randomised routing over the network. The executions of cryptographic algorithms on different architectural configurations are simulated, and the obtained power traces are subjected to DPA attacks. The results show that the proposed architecture introduces a level of non-determinism in the execution that significantly raises the threshold for DPA attacks to succeed. In addition, the performance analysis shows that the improved security does not degrade performance.
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Krishna, Ashwin. „Composing and connecting devices in animal telemetry network“. Kansas State University, 2016. http://hdl.handle.net/2097/32882.
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Master of ScienceDepartment of Computing and Information Sciences
Venkatesh P. Ranganath
As the Internet of Things (IoT) continues to grow, the need for services that span multiple application domains will continue to increase to realise the numerous possibilities enabled by IoT. Today, however, heterogeneity among devices leads to interoperability issues while building a system of systems and often give rise to closed ecosystems. The issues with interoperability are driven by the inability of devices and apps from different vendors to communicate with each other. The interoperability problem forces the users to stick to one particular vendor, leading to vendor lock-in. To achieve interoperability, the users have to do the heavy lifting (at times impossible) of connecting heterogeneous devices. As we slowly move towards system-of-systems and IoT, there is a real need to support heterogeneity and interoperability. A recent effort in Santos Lab developed Medical Device Coordination Framework (MDCF), which was a step to address these issues in the space of human medical systems. Subsequently, we have been wondering if a similar solution can be employed in the area of animal science. In this effort, by borrowing observations from MDCF and knowledge from on-field experience, we have created a demonstration showcasing how a combination of precise component descriptions (via DSL) and communication patterns can be used in software development and deployment to overcome barriers due to heterogeneity, interoperability and to enable an open ecosystem of apps and devices in the space of animal telemetry.
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Gabdurahmanov, Murat, und Simon Trygg. „Analysis and Evaluation of Network Management Solutions : A Comparison of Network Management Solutions Suitable for Networks with 2,500+ Devices“. Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-188793.
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Some companies today are using sub-optimal and nearly obsolete management systems for their networks. Given the large number of different services that are demanded by users, there is a need to adapt the network structure to support the current and potential future demands. As a result, there is a need for new Network Management Solutions (NMSs). The aim of this thesis project is to help a company who uses a NMS called Local Area Network (LAN) Management Solution (LMS). LMS was designed by Cisco for managing LAN networks. However, the company’s demands are growing and they need to expand their network more than expected. Moreover, LMS is designed to only support devices by Cisco, whereas the company wants a universal solution with wide device support from many manufacturers. This thesis presents an analysis of their current system and suggests potential solutions for an upgrade that will meet all of the company’s demands and will have a long operating life. To help find reasonable solutions a thorough evaluation of their existing NMS and network monitoring and management needs was made. This evaluation gave good insights into different aspects of their system. A reasonable solution was found by following a three-step approach, beginning with 82 possible solutions, filtering out and breaking down with each step, until only the most suitable NMS was left. Two NMSs has been proposed as equally suitable replacements: IBM Tivoli Netcool/OMNIbus and ManageEngine OpManager. Regardless of which one is chosen, they both have the following advantages over the company’s existing NMS: they are very stable solutions which can handle a large number of managed devices; they are universal solutions with wide device support, and the company can add custom support if needed; they are user-friendly with the ability to add custom interfaces; and they both have a professional first-line technical support department locally located.Vissa företag använder idag suboptimala och föråldrade övervakningsssystem för sina nätverk. Med tanke på det stora antalet olika tjänster som efterfrågas av användare finns det ett stort behov av att anpassa nätverksstrukturen för att stödja de nuvarande och potentiellt framtida kraven. Som ett resultat finns det ett behov av nya övervakningssystem (Network Management Solutions (NMSs)) för nätverken. Syftet med detta examensarbete är att hjälpa ett företag som använder NMS:en Local Area Network (LAN) Management Solution (LMS). LMS utecklades av Cisco för att hantera lokala nätverk (LANs). Men med tiden har företagets krav förändrats och de har därför behövt expandera sitt nätverk mer än väntat. Dessutom är LMS endast utformad för att hantera enheter tillverkade av Cisco, medan företaget vill ha en universal lösning med stöd för enheter från många olika tillverkare. Denna rapport presenterar en analys av deras nuvarande system, samt föreslår möjliga lösningar som kan ersätta detta. Den nya lösningen ska vara långvarig samt ska uppfylla alla krav företaget ställt. För att hitta lämpliga lösningar har en grundlig utvärdering av den befintliga NMS:en samt en analys av de ställda kraven utförts. Denna analys gav goda insikter i olika aspekter av deras nuvarande system. En lämplig lösning hittades genom att följa en trestegsmetod. Metoden utgick från 82 möjliga lösningar, som efter flera steg av filtrering resulterade i de mest lämpade ersättningssystemen. Två NMS:er har föreslagits som lika lämpliga ersättare: IBM Tivoli Netcool/OMNIbus och ManageEngine OpManager. Oavsett vilken som väljs, har de båda följande fördelar jämfört med den nuvarande NMS:en: de är båda väldigt stabila lösningar som klarar av en stor mängd hanterade enheter; de är universella lösningar med stöd för en stor mängd olika enheter, dessutom går det även att lägga till eget stöd för enheter vid behov; de är användarvänliga och har möjlighet till att anpassa egna gränssnitt; samt att de båda har en professionell first-line teknisk support placerad lokalt i landet.<p>
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Lykouropoulos, Efstathios, Andreas Kostoulas und Zainab Jumaa. „Connect street light control devices in a secure network“. Thesis, Högskolan i Halmstad, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-28180.
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Wireless communications is a constantly progressing technology in network engineering society, creating an environment full of opportunities that are targeting in financial growth, quality of life and humans prosperity. Wireless security is the science that has as a goal to provide safe data communication between authorized users and prevent unauthorized users from gaining access, deny access, damage or counterfeit data in a wireless environment. In order to success it uses layers of protection that consist of software and hardware mechanisms that are able to monitor network’s behavior and in coordination provide a safe and secure environment for the user. In this thesis, a scientific research will be conducted in a given wireless network topology designed for an original application. This is about an intelligent street lightning system and it has already been implemented by Greinon Engineering which is the company that we are cooperating with. It is a matter of great importance that this thesis was conducted under real life criteria and in cooperation with an engineering company. This means that our programming, our ideas, our study research were all rotated and concentrated in certain type of hardware – software and network topology. In this thesis there is a detailed overview of basic wireless security mechanisms – vulnerabilities – types of attacks and countermeasures focused on 802.11b protocol. Moreover there will be security weak point’s analysis on the given industrial network; our proposals to protect and secure this network based on our threat analysis of the current system. There is an analysis on the most up to date VPN security implementations and reasoning that guided our team to conclude in a specific procedure - protocol and implementation, including limitation factors – obstacles faces during this procedure. During this research iterative approach in procedures – ideas and implementation attempts is followed. Basic goal is to provide security solutions that are easy applicable, low cost, easy to maintain and monitor.
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Altrabsheh, Bilal. „Investigation of low cost techniques for realising microwave and millimeter-wave network analysers“. Thesis, University of Surrey, 2003. http://epubs.surrey.ac.uk/843309/.
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The work presented in this thesis is on the development of reliable low cost measurement systems for measuring microwave and millimetre-wave devices. The purpose of this work is to find techniques which use multiple power detectors and can measure magnitude and phase without the need for expensive superheterodyne receivers. Two novel microwave measurement systems have been designed with the intention of providing a measurement facility which enables the characterisation of both active and passive devices in terms of their scattering parameters. The first method is based on using a multistate reflectometer, which uses dielectric waveguide in the frequency range of 110GHz up to 170GHz. The dielectric multistate reflectometer is a four-port reflectometer, which uses a programmable phase shifter to give a flat relative phase shift over the entire frequency range of the dielectric waveguides used in the multistate reflectometer. The phase shifter has an eccentric rotating cylinder with an offset axis to allow a number of different phase shifts to the wave travelling in the dielectric waveguides in the multistate reflectometer. This system has been developed as an equivalent to a one-port network analyser. The second method is based on using the multi-probe reflectometer in which the standing wave in a line is measured using a number of fixed detector probes. A microstrip line prototype in the frequency range of 1GHz to 5.5GHz has been demonstrated and the design of a monolithic microwave integrated circuit (MMIC) version for the frequency range of 40GHz to 325GHz has been earned out. Improved methods of calibration of the system have been derived as well as different methods for error correction. The realisation of a full two-port network analyser using the technique has been demonstrated. Key words: dielectric multistate reflectometer, programmable phase shifter, multi-probe reflectometer, detection, microwave measurement, millimetre-wave measurement, calibration, error corrections.
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McMahon, Michael J. „An approach for enhanced management of network-attached devices“. abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1442840.
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Deng, Shuo. „Intelligent network selection and energy reduction for mobile devices“. Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/99819.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 137-142).
The popularity of mobile devices has stimulated rapid progress in both Wi-Fi and cellular technologies. Before LTE was widely deployed, Wi-Fi speeds dominated cellular network speeds. But that is no longer true today. In a study we conducted with a crowd-sourced measurement tool used by over 1,000 users in 16 countries, we found that 40% of the time LTE outperforms Wi-Fi, and 75% of the time the difference between LTE and Wi-Fi throughput is higher than 1 Mbits/s. Thus, instead of the currently popular "always prefer Wi-Fi" policy, we argue that mobile devices should use the best available combination of networks: Wi-Fi, LTE, or both. Selecting the best network combination, however, is a challenging problem because: 1) network conditions vary with both location and time; 2) many network transfers are short, which means that the decision must be made with low overhead; and, 3) the best choice is determined not only by best network performance, but also constrained by practical factors such as monetary cost and battery life. In this dissertation, we present Delphi, a software controller for network selection on mobile devices. Delphi makes intelligent network selection decisions according to current network conditions and monetary cost concerns, as well as battery-life considerations. Our experiments show that Delphi reduces application network transfer time by 46% for web browsing and by 49% for video streaming, compared with Android's default policy of always using Wi-Fi when it is available. Delphi can also be configured to achieve high throughput while being energy efficient; in this configuration, it achieves 1.9 x the through-put of Android's default policy while only consuming 6% more energy. Delphi improves performance but uses the cellular network more extensively than the status quo, consuming more energy than before. To address this problem, we develop a general method to reduce the energy consumption of cellular interfaces on mobile devices. The key idea is to use the statistics of data transfers to determine the best times at which to put the radio in different power states. These techniques not only make Delphi more useful in practice but can be deployed independently without Delphi to improve energy efficiency for any cellular-network-enabled devices. Experiments show that our techniques reduce energy consumption by 15% to 60% across various traffic patterns.
by Shuo Deng.
Ph. D.
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Qian, Xiaolan 1977. „A protocol for a wireless network of mobile devices“. Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86494.
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Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.Includes bibliographical references (leaf 53).
by Xiaolan Qian.
S.B.and M.Eng.
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Guulay, Biniam Gebregergs. „CheesePi: Measuring Home Network Performance Using Dedicated Hardware Devices“. Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-184917.
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Internet users may not get the service quality promised by theirproviders, and also may not know what service they can receive.When users experience poor Internet connection performance, itis not easy to identify the source of the problem. We developCheesePi, a distributed measurement system that measures theInternet connection experience of home users based on some net-work performance attributes (e.g. latency, packet loss rate, andWiFi signal quality). The CheesePi runs on a Raspberry Pi (acredit card sized computer) connected to the user’s home networkas a measurement agent. It is important to measure the networkperformance from the user’s side since it is difficult to measureeach individual’s link from the operator (provider) side. Eachmeasurement agent conducts measurement periodically withoutdisturbing the user’s Internet quality. Measurements are con-ducted during popular media events from SICS (Swedish Insti-tute of Computer Science) and student accommodations. Themeasurement results show customers with an Ethernet connectionexperienced significantly better latency and packet loss comparedto WiFi users. In most of the measurements users at SICS per-ceived better latency and packet loss compared to the users at thestudent accommodation. We also quantify how customers experi-enced lower performance when streaming from websites which donot use CDN technology compared to the websites which do useCDN, particularly during popular media events.CheesePi
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Nyrönen, P. (Pekka). „Convolutional neural network based super-resolution for mobile devices“. Master's thesis, University of Oulu, 2018. http://urn.fi/URN:NBN:fi:oulu-201812083250.
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Super-resolution is a challenging problem of restoring details lost to diffraction in the image capturing process. Degradations from the environment and the imaging device increase its difficulty, and they are strongly present in mobile phone cameras. The latest promising approaches involve convolutional neural networks, but little testing has been done on degraded images. Also, sizes of neural networks raise a question of their applicability on mobile devices. A wide review of published super-resolution neural networks is done. Four of the network architectures are chosen, and their TensorFlow models are trained and tested for their output quality on high quality and degraded images and compared against bicubic interpolation with sharpening. For the first time, MTF and CPIQ acutance responses are measured from their outputs after processing photographs of a resolution chart. Their execution times on a mobile device are measured for small image sizes and typical phone camera photo sizes. It is shown that the networks are able to learn degradation resilience, and that quality of their results surpasses that of the bicubic interpolations with sharpening. However, even the lightest models still take a considerable time to process images on a mobile device. Moreover, it is shown that the current way of training and evaluating super-resolution neural networks with high quality images is inadequate for practical purposes, and that degradations have to be incorporated into training data in order to overcome the problemSuperresoluutio on haastava diffraktion kuvaa otettaessa hävittämien yksityiskotien palautusongelma. Ympäristöstä ja kuvantamislaitteistosta syntyvät rappeumat lisäävät sen vaikeutta, ja ne ovat voimakkaasti läsnä matkapuhelinten kameroissa. Viimeisimmät lupaavat lähestymistavat hyödyntävät konvoluutioneuroverkkoja, mutta niiden testausta heikkolaatuisilla kuvilla on tehty vähän. Lisäksi neuroverkkojen koot herättävät kysymyksen niiden käytettävyydestä mobiililaitteilla. Julkaistuista superresoluutioverkoista tehdään laaja katsaus. Neljän valitun verkkoarkkitehtuurin TensorFlow-mallien ulostulojen laatua testataan puhtailla ja heikompilaatuisilla kuvilla ja tuloksia verrataan terävöitettyyn kuutiolliseen interpolaatioon. Ensimmäistä kertaa MTF- ja CPIQ-terävyysvaste mitataan niiden ulostulokuvista niiden käsiteltyä valokuvia resoluutiokartasta. Mallien suoritusaikoja mitataan niin pienille kuville kuin tyypillisille kännykkäkameroiden kuvakoille. Tulokset osoittavat, että verkot pystyvät oppimaan kestäviksi laadun heikennyksille, ja että niiden tulosten laatu ylittää terävöitetyn kuutiollisen interpolaation tulokset. Kevyimmätkin mallit vaativat kuitenkin huomattavasti laskenta-aikaa mobiililaitteella. Lisäksi osoitetaan, että nykyinen tapa kouluttaa ja arvioida superresoluutioneuroverkkoja korkealaatuisilla kuvilla on riittämätön käytännön tarkoitusperiin, ja että laadun heikennys on sisällytettävä koulutusaineistoon ongelman yli pääsemiseksi
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Krkusic, Enis. „Security of the mobile devices in VäxjöKommun and corporation“. Thesis, Växjö University, School of Mathematics and Systems Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-6253.
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Astistova, T. I., und O. B. Typa. „Chatbot development for Telegram social network“. Thesis, Київський національний університет технологій та дизайну, 2021. https://er.knutd.edu.ua/handle/123456789/19330.
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Zhou, Wei. „Autonomous smart antenna systems for future mobile devices“. Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/9959.
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Along with the current trend of wireless technology innovation, wideband, compact size, low-profile, lightweight and multiple functional antenna and array designs are becoming more attractive in many applications. Conventional wireless systems utilise omni-directional or sectored antenna systems. The disadvantage of such antenna systems is that the electromagnetic energy, required by a particular user located in a certain direction, is radiated unnecessarily in every direction within the entire cell, hence causing interference to other users in the system. In order to limit this source of interference and direct the energy to the desired user, smart antenna systems have been investigated and developed. This thesis presents the design, simulation, fabrication and full implementation of a novel smart antenna system for future mobile applications. The design and characterisation of a novel antenna structure and four-element liner array geometry for smart antenna systems are proposed in the first stage of this study. Firstly, a miniaturised microstrip-fed planar monopole antenna with Archimedean spiral slots to cover WiFi/Bluetooth and LTE mobile applications has been demonstrated. The fundamental structure of the proposed antenna element is a circular patch, which operates in high frequency range, for the purpose of miniaturising the circuit dimension. In order to achieve a multi-band performance, Archimedean spiral slots, acting as resonance paths, have been etched on the circular patch antenna. Different shapes of Archimedean spiral slots have been investigated and compared. The miniaturised and optimised antenna achieves a bandwidth of 2.2GHz to 2.9GHz covering WiFi/Bluetooth (2.45GHz) and LTE (2.6GHz) mobile standards. Then a four-element linear antenna array geometry utilising the planar monopole elements with Archimedean spiral slots has been described. All the relevant parameters have been studied and evaluated. Different phase shifts are excited for the array elements, and the main beam scanning range has been simulated and analysed. The second stage of the study presents several feeding network structures, which control the amplitude and phase excitations of the smart antenna elements. Research begins with the basic Wilkinson power divider configuration. Then this thesis presents a compact feeding network for circular antenna array, reconfigurable feeding networks for tuning the operating frequency and polarisations, a feeding network on high resistivity silicon (HRS), and an ultrawide-band (UWB) feeding network covering from 0.5GHz to 10GHz. The UWB feeding network is used to establish the smart antenna array system. Different topologies of phase shifters are discussed in the third stage, including ferrite phase shifters and planar phase shifters using switched delay line and loaded transmission line technologies. Diodes, FETs, MMIC and MEMS are integrated into different configurations. Based on the comparison, a low loss and high accurate Hittite MMIC analogue phase shifter has been selected and fully evaluated for this implementation. For the purpose of impedance matching and field matching, compact and ultra wideband CPW-to-Microstrip transitions are utilised between the phase shifters, feeding network and antenna elements. Finally, the fully integrated smart antenna array achieves a 10dB reflection coefficient from 2.25GHz to 2.8GHz, which covers WiFi/Bluetooth (2.45GHz) and LTE (2.6GHz) mobile applications. By appropriately controlling the voltage on the phase shifters, the main beam of the antenna array is steered ±50° and ±52°, for 2.45GHz and 2.6GHz, respectively. Furthermore, the smart antenna array demonstrates a gain of 8.5dBi with 40° 3dB bandwidth in broadside direction, and has more than 10dB side lobe level suppression across the scan. The final stage of the study investigates hardware and software automatic control systems for the smart antenna array. Two microcontrollers PIC18F4550 and LPC1768 are utilised to build the control PCBs. Using the graphical user interfaces provided in this thesis, it is able to configure the beam steering of the smart antenna array, which allows the user to analyse and optimise the signal strength of the received WiFi signals around the mobile device. The design strategies proposed in this thesis contribute to the realisation of adaptable and autonomous smart phone systems.
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Coue, Dominique Xavier Henri Leon. „Feedforward artificial neural network design utilising subthreshold mode CMOS devices“. Thesis, University of Plymouth, 1997. http://hdl.handle.net/10026.1/1633.
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This thesis reviews various previously reported techniques for simulating artificial neural networks and investigates the design of fully-connected feedforward networks based on MOS transistors operating in the subthreshold mode of conduction as they are suitable for performing compact, low power, implantable pattern recognition systems. The principal objective is to demonstrate that the transfer characteristic of the devices can be fully exploited to design basic processing modules which overcome the linearity range, weight resolution, processing speed, noise and mismatch of components problems associated with weak inversion conduction, and so be used to implement networks which can be trained to perform practical tasks. A new four-quadrant analogue multiplier, one of the most important cells in the design of artificial neural networks, is developed. Analytical as well as simulation results suggest that the new scheme can efficiently be used to emulate both the synaptic and thresholding functions. To complement this thresholding-synapse, a novel current-to-voltage converter is also introduced. The characteristics of the well known sample-and-hold circuit as a weight memory scheme are analytically derived and simulation results suggest that a dummy compensated technique is required to obtain the required minimum of 8 bits weight resolution. Performance of the combined load and thresholding-synapse arrangement as well as an on-chip update/refresh mechanism are analytically evaluated and simulation studies on the Exclusive OR network as a benchmark problem are provided and indicate a useful level of functionality. Experimental results on the Exclusive OR network and a 'QRS' complex detector based on a 10:6:3 multilayer perceptron are also presented and demonstrate the potential of the proposed design techniques in emulating feedforward neural networks.
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Kao, Yi-Hsuan. „Optimizing task assignment for collaborative computing over heterogeneous network devices“. Thesis, University of Southern California, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10124490.
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The Internet of Things promises to enable a wide range of new applications involving sensors, embedded devices and mobile devices. Different from traditional cloud computing, where the centralized and powerful servers offer high quality computing service, in the era of the Internet of Things, there are abundant computational resources distributed over the network. These devices are not as powerful as servers, but are easier to access with faster setup and short-range communication. However, because of energy, computation, and bandwidth constraints on smart things and other edge devices, it will be imperative to collaboratively run a computational-intensive application that a single device cannot support individually. As many IoT applications, like data processing, can be divided into multiple tasks, we study the problem of assigning such tasks to multiple devices taking into account their abilities and the costs, and latencies associated with both task computation and data communication over the network.
A system that leverages collaborative computing over the network faces highly variant run-time environment. For example, the resource released by a device may suddenly decrease due to the change of states on local processes, or the channel quality may degrade due to mobility. Hence, such a system has to learn the available resources, be aware of changes and flexibly adapt task assignment strategy that efficiently makes use of these resources.
We take a step by step approach to achieve these goals. First, we assume that the amount of resources are deterministic and known. We formulate a task assignment problem that aims to minimize the application latency (system response time) subject to a single cost constraint so that we will not overuse the available resource. Second, we consider that each device has its own cost budget and our new multi-constrained formulation clearly attributes the cost to each device separately. Moving a step further, we assume that the amount of resources are stochastic processes with known distributions, and solve a stochastic optimization with a strong QoS constraint. That is, instead of providing a guarantee on the average latency, our task assignment strategy gives a guarantee that p% of time the latency is less than t, where p and t are arbitrary numbers. Finally, we assume that the amount of run-time resources are unknown and stochastic, and design online algorithms that learn the unknown information within limited amount of time and make competitive task assignment.
We aim to develop algorithms that efficiently make decisions at run-time. That is, the computational complexity should be as light as possible so that running the algorithm does not incur considerable overhead. For optimizations based on known resource profile, we show these problems are NP-hard and propose polynomial-time approximation algorithms with performance guarantee, where the performance loss caused by sub-optimal strategy is bounded. For online learning formulations, we propose light algorithms for both stationary environment and non-stationary environment and show their competitiveness by comparing the performance with the optimal offline policy (solved by assuming the resource profile is known).
We perform comprehensive numerical evaluations, including simulations based on trace data measured at application run-time, and validate our analysis on algorithm's complexity and performance based on the numerical results. Especially, we compare our algorithms with the existing heuristics and show that in some cases the performance loss given by the heuristic is considerable due to the sub-optimal strategy. Hence, we conclude that to efficiently leverage the distributed computational resource over the network, it is essential to formulate a sophisticated optimization problem that well captures the practical scenarios, and provide an algorithm that is light in complexity and suggests a good assignment strategy with performance guarantee.
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Nafziger, Jonathan W. „A Novel Cache Migration Scheme in Network-on-Chip Devices“. University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1282327354.
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Lindqvist, Anna. „Threats to smart buildings : Securing devices in a SCADA network“. Thesis, Linköpings universitet, Institutionen för datavetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176723.
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This paper examines the possibilities of performing tests with the aim to ensure that devices in a SCADA network can be deemed secure before deployment. SCADA systems are found in most industries and have recently seen an increased use in building automation, most importantly the healthcare sector, which means that a successful attack toward such a system could endanger lives of patients and healthcare professionals.The method of testing was created to examine whether devices conflicted with the security flaws identified by OWASP IoT Top 10 list, meaning that OWASP IoT Top 10 was the foundation for the methodology used in this paper.Results of the tests show that the devices used in testing are not in conflict with the OWASP IoT Top 10 list when using the default settings. However, some settings that can be enabled on the devices would constitute a security risk if enabled.
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Dikme, Altay. „A Quantum Neural Network for Noisy Intermediate Scale Quantum Devices“. Thesis, KTH, Tillämpad fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-300394.
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Neural networks have helped the field of machine learning grow tremendously in the past decade, and can be used to solve a variety of real world problems such as classification problems. On another front, the field of quantum computing has advanced, with quantum devices publicly available via the cloud. The availability of such systems has led to the creation of a new field of study, Quantum Machine Learning, which attempts to create quantum analogues of classical machine learning techniques. One such method is the Quantum Neural Network (QNN) inspired by classical neural networks. In this thesis we design a QNN compatible with Noisy Intermediate Scale Quantum (NISQ) devices, which are characterised by a limited number of qubits and small decoherence times. Furthermore we provide an implementation of the QNN classifier using the open source quantum computing software development kit, Qiskit provided by IBM. We perform a binary classification experiment on a subset of the MNIST data set, and our results showed a classification accuracy of 80.6% for a QNN with circuit depth 20.Neurala nätverk har varit en stor del av utvecklingen av maskininlärning som ett forskningsområde i det senaste årtiondet, och dessa nätverk har flera appliceringsområden, som till exempel klassificieringsproblemet. Parallelt med denna utveckling, har forskning kring kvantdatorer vuxit fram, med flera kvantsystem allmänt tillgängliga via molnet. Denna tillgänglighet har lett till skapandet av ett nytt forskningsområde; kvantmaskininlärning, som försöker skapa motsvarigheter till klassiska maskininlärningsmetoder på kvantdatorer. En sån metod är kvantneurala nätverk som inspireras av klassiska neurala nätverk. I denna avhandling designar vi ett kvantneuralt närverk som är kompatibel med nuvarande kvantsystem, som kännetecknas av ett begränsat antal qubits och korta dekoherenstider. Dessutom tillhandahåller vi en implementering av en klassificerare med ett kvantneuralt nätverk, med hjälp av IBMs programvaruutvecklingsmiljö Qiskit. Vi utför ett binärt klassificeringsexperiment på en delmängd av MNIST-datamängden, och våra resultatvisar en klassificeringsnoggrannhet på 80,6% för ett kvantneuralt nätverk med kretsdjup 20.
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Phillips, Ian D. „OTDM network processing using all-optical and electro-optical devices“. Thesis, Aston University, 1998. http://publications.aston.ac.uk/15370/.
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The current optical communications network consists of point-to-point optical transmission paths interconnected with relatively low-speed electronic switching and routing devices. As the demand for capacity increases, then higher speed electronic devices will become necessary. It is however hard to realise electronic chip-sets above 10 Gbit/s, and therefore to increase the achievable performance of the network, electro-optic and all-optic switching and routing architectures are being investigated. This thesis aims to provide a detailed experimental analysis of high-speed optical processing within an optical time division multiplexed (OTDM) network node. This includes the functions of demultiplexing, 'drop and insert' multiplexing, data regeneration, and clock recovery. It examines the possibilities of combining these tasks using a single device. Two optical switching technologies are explored. The first is an all-optical device known as 'semiconductor optical amplifier-based nonlinear optical loop mirror' (SOA-NOLM). Switching is achieved by using an intense 'control' pulse to induce a phase shift in a low-intensity signal propagating through an interferometer. Simultaneous demultiplexing, data regeneration and clock recovery are demonstrated for the first time using a single SOA-NOLM. The second device is an electroabsorption (EA) modulator, which until this thesis had been used in a uni-directional configuration to achieve picosecond pulse generation, data encoding, demultiplexing, and 'drop and insert' multiplexing. This thesis presents results on the use of an EA modulator in a novel bi-directional configuration. Two independent channels are demultiplexed from a high-speed OTDM data stream using a single device. Simultaneous demultiplexing with stable, ultra-low jitter clock recovery is demonstrated, and then used in a self-contained 40 Gbit/s 'drop and insert' node. Finally, a 10 GHz source is analysed that exploits the EA modulator bi-directionality to increase the pulse extinction ratio to a level where it could be used in an 80 Gbit/s OTDM network.
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Pierfederici, Eugenio. „Inferring the behaviour and security of networked devices via communication analysis“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19418/.
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In the last years the number of devices connected to the Internet has been increasing exponentially and it has reached huge numbers, just days ago the RIPE Network Coordination Center announced it run out of IPv4 addresses.
As a consequence, it's extremely complex to control what is happening on the network and what, or whom, a device is communicating with. We are losing control over many of our devices. It's becoming everyday more difficult to know what the device is doing and what is it sharing on the Internet.
Luckily, in the last years the attention to security, privacy and awareness is ever increasing: the users pay more attention to what their devices are doing and care about it.
While big software (like the operative systems and most mobile devices) make available an increasing number of tools to monitor the device traffic, some devices cannot be inspected or those same tools may be forged in a way that makes it impossible to detect some specific malicious behaviours.
Until now every successful method to detect or filter the behaviour of the devices has been trying to only detect anomalies or manually lock some specific behaviours; this means nobody ever tried to understand at a discrete
level of accuracy what the device does relying only on the analysis of the metadata of the traffic intercepted.
That’s why in this thesis I defined a model able to detect the behaviour which is occurring on the device by the mere observation of its network traffic. In doing so, I first defined a model that takes the raw low-level information regarding the communications occurring, process them and return information about the high-level operations occurring on the device. I then built a demo that uses that model and demonstrates its feasibility. The data used are low-level information on the traffic without ever inspecting its payload.
To improve the efficiency of the algorithm, I also use a form of Recurrent Neural Networks to finally infer the device behaviour.
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Nuangjamnong, Chompu. „An investigation of network management“. Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2009. https://ro.ecu.edu.au/theses/1836.
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Modern information networks are so integral to everyday business and society that even short period of downtime can adversely affect many thousands of users. Because of the inherently heterogeneous nature of network devices and protocols, these networks are typically administered using a range of command-line interface (CLI) tools and graphical user interface (GUI) tools from many different vendors. Mastering all these different tools takes time and experience and it is often hard to get an integrated, high-level view of the network. This means network administrators may inadve1iently misconfigure their systems or overlook a potential threat.
To explore some of these issues, this project evaluated State Model Diagrams (SMDs) as both a network administration tool and as a way of teaching administrators about fundamental networking concepts. SMDs are an abstract modelling tool that allows experienced practitioners and novices to grasp the complexities of network administration by identifying essential networking objects, processes, and concepts without getting bogged down in too many distracting details.
In 2007 and 2008, ECU post-graduate students doing networking courses were given a comprehensive demonstration of SMDs. The students then completed a questionnaire on how they thought SMDs compared to other network tools and how they thought SMDs could be practically applied. A result of twenty (48.8%) of positive responses from among 41 participating students have clearly demonstrated that SMDs were potentially useful as a NM tool for managing network systems and provided a richer conceptual understanding aligned with that of an expert.
In this research study, the results showed that SMDs would help most of the participants understand and administer their networks, and a majority believed that SMDs would help reduce the fundamental complexity of their multi-tool work environment. Lastly, fu1iher research is required with a larger and more varied population but the results so far indicate that SMDs are a valuable tool for network administrators.
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Chu, Guang Yong. „Photonic devices for next generation fiber-to-the-home access network“. Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/386564.
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It would be unaffordable if the WDM-PON technologies were directly applied for massive deployment. Hence, the potential WDM-PON is to be integrated and improved in order to adapt it for NGPON and the future 5G. The UDWDM-PON can be considered as an ultimate solution for the next-generation access network capable of providing unlimited bandwidth for each user, thanks to the coherent detection.
Plenty of scientists have believed that it is crucial to increase the operating speed and maximum reach of WDM-PON, while it has no sense if people achieve them without a ordable cost.
In order to apply them cost-effciently, the system should require colorless ONUs and bidirectional systems. It is desired that the whole system use modulators on a low bias consumption, even limit the number of amplifiers.
However, for bidirectional transmission the backscattering effects would limit the performance if we want to reuse the carrier from OLT. So, we should design a method to separate the wavelength between upstream and downstream.
The traditional UDWDM-PON uses 2 laser at ONU, in this thesis, the single-DFB based ONUs are presented with integrated devices.
What is the most plausible configuration? The photonic devices such as RSOA, DEML, FML with advanced configurations are presented in this thesis with different applications.
The proposed thesis includes these parts: key devices for WDM-PON and the chirp parameters of these integrated photonic devices are measured, the polarization independent RSOA with different applications is also included, demonstration of dual output DEML with bidirectional coherent UDWDM-PON transmission, mitigating residual AM of DEML for phase modulation, and fast tuning for the UDWDM channel via FML are described.Por sus altos requerimientos técnicos, sería inasumible aplicar las tecnologías WDM-PON directamente para el despliegue masivo de Fiber-to-the-Home de nueva generación. Por lo tanto, el potencial se WDM-PON se debe integrar y mejorar con el fin de adaptarlo para NGPON y el futuro 5G. Hoy dia, operadores, usuarios y científicos, ven crucial augmentar la velocitat de funcionament y el alcance de las redes de acceso PON, si bien no tiene sentido conseguirlo con un coste inasequible. El UDWDM-PON puede considerarse como una solución definitiva para la red de acceso de próxima generación, capaz de proporcionar ancho de banda ilimitado para cada usuario, gracias a la detección coherente, por lo que en esta tesis se aborda su realización con un coste e integración prácticos. Con el fin de aplicarlos de manera rentable, el sistema debería exigir a las ONU que sean idénticas, si láseres preseleccionados o incoloros, y ser bidireccionales. Se desea que el conjunto de moduladores del sistema tengan en un bajo consumo, e incluso limitar el número de amplificadores. Sin embargo, para la transmisión bidireccional los efectos de retrodispersión limitarían el rendimiento si queremos volver a utilizar la portadora generada en la OLT. Por lo tanto, debemos diseñar un método para separar la longitud de onda en las transmisiones de bajada y de retorno del usuario a la central. El tradicional UDWDM-PON utiliza 2 láseres en la ONU; en esta tesis, las ONUs usan dispositivos integrados basados en un sólo DFB. ¿Cuál es la configuración más plausible? Los dispositivos fotónicos como RSOA, DEML, FML con configuraciones avanzadas se presentan en esta tesis con diferentes aplicaciones, que resuelven distintos problemas técnicos. La tesis incluye las siguientes partes: análisis y medida de dispositivos fotónicos clave para WDM-PON con modulación de fase, la independencia a la polarización de RSOA con diferentes aplicaciones, demostración de DEML con doble salida para transmisión bidireccional coherente UDWDM-PON, mitigación de AM residual de DEML para la modulación de fase, y la sintonía rápida de canal de UDWDM a través de FML.
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Murphy, Ethan Kane. „Radial-Basis-Function Neural Network Optimization of Microwave Systems“. Link to electronic thesis, 2002. http://www.wpi.edu/Pubs/ETD/Available/etd-0113103-121206/.
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Master's Project (M.S.) -- Worcester Polytechnic Institute.Keywords: optimization technique; microwave systems; optimization technique; neural networks; QuickWave 3D. Includes bibliographical references (p. 68-71).
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Martínez, Anny. „An ontology-based approach toward the configuration of heterogeneous network devices“. Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/299803.
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Despite the numerous efforts of standardization, semantic issues remain in effect in many subfields of networking. The inability to exchange data unambiguously between information systems and human resources is an issue that hinders technology implementation, semantic interoperability, service deployment, network management, technology migration, among many others. In this thesis, we will approach the semantic issues in two critical subfields of networking, namely, network configuration management and network addressing architectures. The fact that makes the study in these areas rather appealing is that in both scenarios semantic issues have been around from the very early days of networking. However, as networks continue to grow in size and complexity current practices are becoming neither scalable nor practical.
One of the most complex and essential tasks in network management is the configuration of network devices. The lack of comprehensive and standard means for modifying and controlling the configuration of network elements has led to the continuous and extended use of proprietary Command Line Interfaces (CLIs). Unfortunately, CLIs are generally both, device and vendor-specific. In the context of heterogeneous network infrastructures---i.e., networks typically composed of multiple devices from different vendors---the use of several CLIs raises serious Operation, Administration and Management (OAM) issues. Accordingly, network administrators are forced to gain specialized expertise and to continuously keep knowledge and skills up to date as new features, system upgrades or technologies appear. Overall, the utilization of proprietary mechanisms allows neither sharing knowledge consistently between vendors' domains nor reusing configurations to achieve full automation of network configuration tasks---which are typically required in autonomic management. Due to this heterogeneity, CLIs typically provide a help feature which is in turn an useful source of knowledge to enable semantic interpretation of a vendor's configuration space. The large amount of information a network administrator must learn and manage makes Information Extraction (IE) and other forms of natural language analysis of the Artificial Intelligence (AI) field key enablers for the network device configuration space. This thesis presents the design and implementation specification of the first Ontology-Based Information Extraction (OBIE) System from the CLI of network devices for the automation and abstraction of device configurations. Moreover, the so-called semantic overload of IP addresses---wherein addresses are both identifiers and locators of a node at the same time---is one of the main constraints over mobility of network hosts, multi-homing and scalability of the routing system. In light of this, numerous approaches have emerged in an effort to decouple the semantics of the network addressing scheme. In this thesis, we approach this issue from two perspectives, namely, a non-disruptive (i.e., evolutionary) solution to the current Internet and a clean-slate approach for Future Internet. In the first scenario, we analyze the Locator/Identifier Separation Protocol (LISP) as it is currently one of the strongest solutions to the semantic overload issue. However, its adoption is hindered by existing problems in the proposed mapping systems. Herein, we propose the LISP Redundancy Protocol (LRP) aimed to complement the LISP framework and strengthen feasibility of deployment, while at the same time, minimize mapping table size, latency time and maximize reachability in the network. In the second scenario, we explore TARIFA a Next Generation Internet architecture and introduce a novel service-centric addressing scheme which aims to overcome the issues related to routing and semantic overload of IP addresses.A pesar de los numerosos esfuerzos de estandarización, los problemas de semántica continúan en efecto en muchas subáreas de networking. La inabilidad de intercambiar data sin ambiguedad entre sistemas es un problema que limita la interoperabilidad semántica. En esta tesis, abordamos los problemas de semántica en dos áreas: (i) la gestión de configuración y (ii) arquitecturas de direccionamiento. El hecho que hace el estudio en estas áreas de interés, es que los problemas de semántica datan desde los inicios del Internet. Sin embargo, mientras las redes continúan creciendo en tamaño y complejidad, los mecanismos desplegados dejan de ser escalabales y prácticos. Una de las tareas más complejas y esenciales en la gestión de redes es la configuración de equipos. La falta de mecanismos estándar para la modificación y control de la configuración de equipos ha llevado al uso continuado y extendido de interfaces por líneas de comando (CLI). Desafortunadamente, las CLIs son generalmente, específicos por fabricante y dispositivo. En el contexto de redes heterogéneas--es decir, redes típicamente compuestas por múltiples dispositivos de distintos fabricantes--el uso de varias CLIs trae consigo serios problemas de operación, administración y gestión. En consecuencia, los administradores de red se ven forzados a adquirir experiencia en el manejo específico de múltiples tecnologías y además, a mantenerse continuamente actualizados en la medida en que nuevas funcionalidades o tecnologías emergen, o bien con actualizaciones de sistemas operativos. En general, la utilización de mecanismos propietarios no permite compartir conocimientos de forma consistente a lo largo de plataformas heterogéneas, ni reutilizar configuraciones con el objetivo de alcanzar la completa automatización de tareas de configuración--que son típicamente requeridas en el área de gestión autonómica. Debido a esta heterogeneidad, las CLIs suelen proporcionar una función de ayuda que fundamentalmente aporta información para la interpretación semántica del entorno de configuración de un fabricante. La gran cantidad de información que un administrador debe aprender y manejar, hace de la extracción de información y otras formas de análisis de lenguaje natural del campo de Inteligencia Artificial, potenciales herramientas para la configuración de equipos en entornos heterogéneos. Esta tesis presenta el diseño y especificaciones de implementación del primer sistema de extracción de información basada en ontologías desde el CLI de dispositivos de red, para la automatización y abstracción de configuraciones. Por otra parte, la denominada sobrecarga semántica de direcciones IP--en donde, las direcciones son identificadores y localizadores al mismo tiempo--es una de las principales limitaciones sobre mobilidad, multi-homing y escalabilidad del sistema de enrutamiento. Por esta razón, numerosas propuestas han emergido en un esfuerzo por desacoplar la semántica del esquema de direccionamiento de las redes actuales. En esta tesis, abordamos este problema desde dos perspectivas, la primera de ellas una aproximación no-disruptiva (es decir, evolucionaria) al problema del Internet actual y la segunda, una nueva propuesta en torno a futuras arquitecturas del Internet. En el primer escenario, analizamos el protocolo LISP (del inglés, Locator/Identifier Separation Protocol) ya que es en efecto, una de las soluciones con mayor potencial para la resolucion del problema de semántica. Sin embargo, su adopción está limitada por problemas en los sistemas de mapeo propuestos. En esta tesis, proponemos LRP (del inglés, LISP Redundancy Protocol) un protocolo destinado a complementar LISP e incrementar la factibilidad de despliegue, a la vez que, reduce el tamaño de las tablas de mapeo, tiempo de latencia y maximiza accesibilidad. En el segundo escenario, exploramos TARIFA una arquitectura de red de nueva generación e introducimos un novedoso esquema de direccionamiento orientado a servicios.
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Mandowara, Piyush. „Live video streaming for handheld devices over an ad hoc network“. Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/941.
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Larsson, Magnus. „Sanitization of embedded network devices : Investigation of vendor’s factory reset procedure“. Thesis, KTH, Radio Systems Laboratory (RS Lab), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-166305.
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Embedded devices such as routers, switches, and firewalls commonly have sensitive information stored on them such as passwords, cryptographic keys, and information about the network around them and services that these device(s) provide. When disposing of or reselling this equipment in the secondary market it is crucial to erase this sensitive information. However, there is an important question that must be asked: Do the erase commands and routines offered by the device manufacturers actually erase the sensitive data? This thesis investigates methods and tools to determine the completeness of this erasure in some common network devices. These methods are used on a sample of networking equipment found to still contain sensitive information after being erased according to vendor recommendations. A computer program was developed to show how this information can be removed. The information in this document is useful for equipment owners, brokers and others looking to remarket their current equipment; all of whom want to minimize the risk of leaking sensitive data to other parties.Nätverksutrustning såsom routrar, switchar och brandväggar har ofta känslig information lagrad internt, som lösenord, kryptografiska nycklar, information om nätverket runt dem samt tjänster de tillhandahåller. Om denna utrustning ska säljas på andrahandsmarkanden eller på annat sätt byta ägare är det viktigt att all känslig information raderas. Men kan man lita på att raderings rutiner och metoder som tillhandahålls av tillverkaren verkligen raderar känslig data? Denna avhandling undersöker lämpliga verktyg och metoder för att granska vilken information som minnen i inbyggda system innehåller. Dessa metoder testas praktiskt på några system som visar sig ha kvar känslig information efter att de raderats enligt tillverkarens rekommendationer. Ett datorprogram som demonstrerar hur denna information kan undersökas och raderas finns med som en del av avhandlingen. Informationen i detta dokument är användbar för ägare av datakomutrustning, mäklare av sådana samt andra som vill minimera risken för att läcka känslig information vid återförsäljning av sin begagnade utrustning.
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Milner, Simon Howard. „In service non-intrusive measurement devices for telephony networks“. Thesis, Manchester Metropolitan University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260851.
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Kalin, John Howard. „Simulating IoT Frameworks and Devices in the Smart Home“. Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78767.
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The rapid growth of the Internet of Things (IoT) has led to a situation where individual manufacturers develop their own communication protocols and frameworks that are often incompatible with other systems. Part of this is due to the use of incompatible communication hardware, and part is due to the entrenched proprietary systems. This has created a heterogeneous communication landscape, where it is difficult for devices to coordinate their efforts. To remedy this, a number of IoT Frameworks have been proposed to provide a common interface between IoT devices. There are many approaches to common frameworks, each with their strengths and weaknesses, but there is no clear winner among them. This thesis presents a virtual network testbed for implementing smart home IoT Frameworks. It consists of a simulated home network made up of multiple Virtual Machines (VM), simulated smart home devices and an implementation of the OpenHAB framework to integrate the devices. Simulated devices are designed to be network- accurate representations of actual devices, a LIFX smart lightbulb was developed and an existing Nest thermostat simulation was integrated. The demonstrated setup serves as a proof of concept for the idea of a home network testbed. Such a testbed could allow for the development of new IoT frameworks or the comparison of existing ones, and it could also serve as an education aid to illustrate how smart home IoT devices communicate with one another.Master of Science
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Kobezak, Philip D. „Frequent Inventory of Network Devices for Incident Response: A Data-driven Approach to Cybersecurity and Network Operations“. Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83375.
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Challenges exist in higher education networks with host inventory and identification. Any student, staff, faculty, or dedicated IT administrator can be the primary responsible personnel for devices on the network. Confounding the problem is that there is also a large mix of personally-owned devices. These network environments are a hybrid of corporate enterprise, federated network, and Internet service provider. This management model has survived for decades based on the ability to identify responsible personnel when a host, system, or user account is suspected to have been compromised or is disrupting network availability for others. Mobile devices, roaming wireless access, and users accessing services from multiple devices has made the task of identification onerous. With increasing numbers of hosts on networks of higher education institutions, strategies such as dynamic addressing and address translation become necessary. The proliferation of the Internet of Things (IoT) makes this identification task even more difficult. Loss of intellectual property, extortion, theft, and reputational damage are all significant risks to research institution networks. Quickly responding to and remediating incidents reduces exposure and risk.
This research evaluates what universities are doing for host inventory and creates a working prototype of a system for associating relevant log events to one or more responsible people. The prototype reduces the need for human-driven updates while enriching the dynamic host inventory with additional information. It also shows the value of associating application and service authentications to hosts. The prototype uses live network data which is de-identified to protect privacy.Master of Science
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Yan, Han. „Smart devices collaboration for energy saving in home networks“. Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S122/document.
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Au cours des dernières années, la révolution numérique a continué sa progression. Les technologies de l'information et des communications (TIC) ont totalement changé la vie quotidienne des gens à leur domicile (concept de « maison numérique »). Pendant ce temps, non seulement le volume des émissions de CO2 produit par les TIC, ce qu'on appelle l'empreinte carbone, est sans cesse en croissance mais elle s'accompagne également d'une hausse du prix de l'électricité, augmentant fortement la part des équipements numériques dans la budget global des ménages. Ainsi, pour des raisons environnementale et économique, réduire la consommation d'énergie dans les nombreux équipements du réseau domestique est devenu un enjeu majeur. Dans ce contexte, la thèse porte sur la conception, l'évaluation et la mise en œuvre d'un ensemble de mécanismes dans le but de répondre aux problèmes de consommation d'énergie sur les réseaux locaux rassemblant les équipements numériques domestiques. Nous proposons un réseau de contrôle qui est formé par des noeuds de contrôle de l'énergie placés au-dessus du réseau traditionnel. Chaque nœud de contrôle est relié à un dispositif en vue de coordonner les états d'alimentation de l'équipement domestique associé.. Un démonstrateur pour un système Home Power Efficiency (HOPE) a également été mis en œuvre. Il démontre la faisabilité de la solution technique que nous proposons pour le contrôle de l'énergie dans un réseau domestique réel avec des scénarios réels qui sont souvent utilisées par utilisateur. Après avoir analysé le mode d'utilisation des équipements du réseau domestique, nous proposons un système de gestion d'énergie qui contrôle ces équipements minimisant ainsi que leur consommation. Le système est basé sur l'analyse des services collaboratifs, chaque service est découpé en blocs fonctionnels atomiques, distribués dans les différents équipements. Cela permet de gérer avec plus de précision les besoins énergétiques de chaque équipement de manière à n'alimenter que les composants nécessaires au service demandé. Pour conclure ces travaux, nous avons également cherché à minimiser les impacts de l'économie d'énergie sur la qualité d'expérience perçue par l'utilisateur (notamment le délai d'activation des services). Nous proposons un système de gestion d'énergie pour des services collaboratifs offrant plusieurs compromis possibles entre la consommation d'énergie et le délai d'activation des services dans un réseau domestique. Il est complété par un algorithme d'apprentissage du comportement des utilisateurs domestiquesIn recent years, Information and Communications Technology (ICT) has totally changed the people daily life in the Digital Home. Meanwhile, not only the amount of CO2 emission of ICT, so called ''footprint'', is increasing without cease, but also the price of electricity is constantly rising. Thus, it is quite important to reduce energy consumption in the home network and home devices for the environmental and economic reasons. In order to cope with this context, the thesis concerns the design, the evaluation, and the implementation of a novel set of mechanisms with the purpose of responding to home network energy consumption problems. We proposed firstly an Overlay Energy Control Network which is formed by the overlay energy control nodes. Each node is connected to one device which forms an overlay control network to coordinate the power states of the device. Then, a testbed for HOme Power Efficiency system (HOPE) is implemented to demonstrate the technical solution for energy control in a real home network environment with several frequently used scenarios. After analyzing user's way of use of their home network equipment, we propose a power management which controls the devices based on the analysis of the collaborative services. These frequently used collaborative services require different functional blocks in different devices. This model provides the possibility to turn on the right requested functional blocks in the right device at the right moment. Finally, based on the former contribution, the collaborative overlay power management offers several possible tradeoffs between the power consumption and the waiting delay in the home network
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Qiao, Wei. „Integrated control of wind farms, facts devices and the power network using neural networks and adaptive critic designs“. Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/29716.
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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.Committee Chair: Ronald G. Harley; Committee Member: David G. Taylor; Committee Member: Deepakraj M. Divan; Committee Member: Ganesh Kumar Venayagamoorthy; Committee Member: Thomas G. Habetler. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Sánchez, Rivera Giovanny. „Efficient multiprocessing architectures for spiking neural network emulation based on configurable devices“. Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/285319.
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The exploration of the dynamics of bioinspired neural networks has allowed neuroscientists to understand some clues and structures of the brain. Electronic neural network implementations are useful tools for this exploration. However, appropriate architectures are necessary due to the extremely high complexity of those networks. There has been an extraordinary development in reconfigurable computing devices within a short period of time especially in their resource availability, speed, and reconfigurability (FPGAs), which makes these devices suitable to emulate those networks.
Reconfigurable parallel hardware architecture is proposed in this thesis in order to emulate in real time complex and biologically realistic spiking neural networks (SNNs). Some relevant SNN models and their hardware approaches have been studied, and analyzed in order to create an architecture that supports the implementation of these SNN models efficiently. The key factors, which involve flexibility in algorithm programmability, high performance processing, low area and power consumption, have been taken into account. In order to boost the performance of the proposed architecture, several techniques have been developed: time to space mapping, neural virtualization, flexible synapse-neuron mapping, specific learning and execution modes, among others.
Besides this, an interface unit has been developed in order to build a bio-inspired system, which can process sensory information from the environment. The spiking-neuron-based system combines analog and digital multi-processor implementations. Several applications have been developed as a proof-of-concept in order to show the capabilities of the proposed architecture for processing this type of information.L'estudi de la dinàmica de les xarxes neuronals bio-inspirades ha permès als neurocientífics entendre alguns processos i estructures del cervell. Les implementacions electròniques d'aquestes xarxes neuronals són eines útils per dur a terme aquest tipus d'estudi. No obstant això, l'alta complexitat de les xarxes neuronals requereix d'una arquitectura apropiada que pugui simular aquest tipus de xarxes. Emular aquest tipus de xarxes en dispositius configurables és possible a causa del seu extraordinari desenvolupament respecte a la seva disponibilitat de recursos, velocitat i capacitat de reconfiguració (FPGAs ). En aquesta tesi es proposa una arquitectura maquinari paral·lela i configurable per emular les complexes i realistes xarxes neuronals tipus spiking en temps real. S'han estudiat i analitzat alguns models de neurones tipus spiking rellevants i les seves implementacions en maquinari , amb la finalitat de crear una arquitectura que suporti la implementació d'aquests models de manera eficient . S'han tingut en compte diversos factors clau, incloent flexibilitat en la programació d'algorismes, processament d'alt rendiment, baix consum d'energia i àrea. S'han aplicat diverses tècniques en l'arquitectura desenvolupada amb el propòsit d'augmentar la seva capacitat de processament. Aquestes tècniques són: mapejat de temps a espai, virtualització de les neurones, mapeig flexible de neurones i sinapsis, modes d'execució, i aprenentatge específic, entre d'altres. A més, s'ha desenvolupat una unitat d'interfície de dades per tal de construir un sistema bio-inspirat, que pot processar informació sensorial del medi ambient. Aquest sistema basat en neurones tipus spiking combina implementacions analògiques i digitals. S'han desenvolupat diverses aplicacions usant aquest sistema com a prova de concepte, per tal de mostrar les capacitats de l'arquitectura proposada per al processament d'aquest tipus d'informació.
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Nguyen, Neal Huynh. „Logging, Visualization, and Analysis of Network and Power Data of IoT Devices“. DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1990.
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There are approximately 23.14 billion IoT(Internet of Things) devices currently in use worldwide. This number is projected to grow to over 75 billion by 2025. Despite their ubiquity little is known about the security and privacy implications of IoT devices. Several large-scale attacks against IoT devices have already been recorded.
To help address this knowledge gap, we have collected a year’s worth of network traffic and power data from 16 common IoT devices. From this data, we show that we can identify different smart speakers, like the Echo Dot, from analyzing one minute of power data on a shared power line.
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Fenn, Edward, und Eric Fornling. „Mapping and identifying misplaced devices on a network by use of metadata“. Thesis, Blekinge Tekniska Högskola, Institutionen för datalogi och datorsystemteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-14687.
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Context. Network placement of devices is an issue of operational security for most companies today. Since a misplaced device can compromise an entire network and in extension, a company, it is essential to keep track of what is placed where. Knowledge is the key to success, and knowing your network is required to make it secure. Large networks however may be hard to keep track of, since employees can connect or unplug devices and make it hard for the administrators to keep updated on the network at all times. Objectives. This analysis focuses on the creation of an analysis method for network mapping based on metadata. This analysis method is to be implemented in a tool that automatically maps a network based on specific metadata attributes. The motivation and goal for this study is to create a method that will improve network mapping with regard to identifying misplaced devices, and to achieve a better understanding of the impact misplaced systems can have on a network. Method. The method for analyzing the metadata was manually checking the network metadata that was gathered by Outpost24 AB’s proprietary vulnerability scanner. By analyzing this metadata, certain attributes were singled out as necessary for the identification. These attributes were then implemented in a probability function that based on the information determines the device type. The results from the probability function are then presented visually as a network graph. A warning algorithm was then run against these results and prompted warnings when finding misplaced devices on subnets. Results. The proposed method is deemed to be 30 878 times faster than the previous method, i.e. the manual control of metadata. It is however not as accurate with an identification rate of between 80% and 93% of devices and correct device type identification of 95-98% of the identified devices. This is as opposed to the previous method, i.e. the manual control of metadata, with 80-93%% identification rate and 100% correct device type identification. The proposed method also flagged 48.9% of the subnets as misconfigured. Conclusion. In conclusion, the proposed method proves that it is indeed possible to identify misplaced devices on networks based on metadata analysis. The proposed method is also considerably faster than the previous method, but does need some further work to be as efficient as the previous method and reach a 100% device type identification rate.Kontext. Placeringen av enheter i nätverk har idag blivit en säkerhetsfråga för de flesta företagen. Eftersom en felplacerad enhet kan äventyra ett helt nätverk, och i förlängning, ett företag så är det essentiellt att ha koll på vad som är placerat vart. Kunskap är nyckeln till framgång, och att ha kunskap om sin nätverksstruktur är avgörande för att göra nätverket säkert. Stora nätverk kan dock vara svåra att ha koll på om anställda kan lägga till eller ta bort enheter, och på så sätt göra det svårt för administratören att ständigt hålla sig uppdaterad om vad som finns vart. Mål. Den här studien fokuserar på skapandet av en analysmetod för att kartlägga ett nätverk baserat på metadata från nätverket. Analysmetoden ska sedan implementeras i ett verktyg som sedan automatiskt kartlägger nätverket utifrån den metadata som valts ut i analysmetoden. Motivationen och målet med den här studien är att skapa en metod som förbättrar nätverkskartläggning med syftet att identifiera felplacerade enheter, och att uppnå en större förståelse för den inverkan felplacerade enheter kan få för ett nätverk. Metod. Metoden för att analysera metadatan var att genom att för hand leta igenom den metadata som Outpost24 ABs sårbarhetsskanner samlade in när den letade efter sårbarheter i ett nätverk. Genom att analysera metadatan så kunde vi singla ut enskilda bitar som vi ansåg vara nödvändiga för att identifiera enhetens typ. Dessa attribut implementerades sedan i en sannolikhetsfunktion som avgjorde vilken typ en enhet hade, baserat på informationen i metadatan. Resultatet från denna sannolikhetsfunktion presenterades sedan visuellt som en graf. En algoritm som matade ut varningar om den hittade felkonfigurerade subnät kördes sedan mot resultaten från sannolikhetsfunktionen. Resultat. Den i den här rapporten föreslagna metoden är fastställt till att vara cirka 30 878 gånger snabbare än föregående metoder, i.e. att leta igenom metadatan för hand. Dock så är den föreslagna metoden inte lika exakt då den har en identifikationsgrad på 80-93% av enheterna på nätverket, och en korrekt identifikationsgrad på enhetstypen på 95-98% av de identifierade enheterna. Detta till skillnad från den föregående metoden som hade 80-93% respektive 100% identifikationsgrad. Den föreslagna metoden identifierade också 48.9% av alla subnät som felkonfigurerade. Sammanfattning. För att sammanfatta så bevisar den föreslagna metoden att det är möjligt att identifiera felplacerade enheter på ett nätverk utifrån en analys av nätverkets metadata. Den föreslagna metoden är dessutom avsevärt snabbare än föregående metoder, men behöver utvecklas mer för att nå samma identifikationsgrad som föregående metoder. Det här arbetet kan ses som ett proof-of-concept gällande identifikation av enheter baserat på metadata, och behöver därför utvecklas för att nå sin fulla potential.
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Xiao, Shuo Electrical Engineering & Telecommunications Faculty of Engineering UNSW. „Transmission power control in body-wearable sensor devices for healthcare monitoring“. Publisher:University of New South Wales. Electrical Engineering & Telecommunications, 2008. http://handle.unsw.edu.au/1959.4/41104.
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Emerging body-wearable sensor devices for continuous health monitoring are severely energy constrained and yet required to offer high communication reliability under fluctuating channel conditions. This thesis aims at investigating the opportunities and challenges in the use of dynamic radio transmit power control for prolonging the lifetime of such devices. We first present extensive empirical evidence that the wireless link quality can change rapidly in body area networks, and a fixed transmit power results in either wasted energy (when the link is good) or low reliability (when the link is bad). We then propose a class of schemes feasible for practical implementation that adapt transmit power in real-time based on feedback information from the receiver. We show conservative, balanced, and aggressive adaptations of our scheme that progressively achieve higher energy savings of 14%-30% in exchange for higher potential packet losses (up to 10%). We also provide guidelines on how the parameters can be tuned to achieve the desired trade-off between energy savings and reliability within the chosen operating environment. Finally, we implement and profile our scheme on a MicaZ mote based platform, demonstrating that energy savings are achievable even with imperfect feedback information, and report preliminary results on the ultra-low-power integrated healthcare monitoring platform from our collaborating partner Toumaz Technology. In conclusion, our work shows adaptive radio transmit power control as a low-cost way of extending the battery-life of severely energy constrained body wearable devices, and opens the door to further optimizations customized for specific deployment scenarios.
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Kasparek, Alexander J. „Secure Key Agreement for Wearable Medical Devices“. Digital WPI, 2019. https://digitalcommons.wpi.edu/etd-theses/1333.
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In this thesis we explore if a proposed random binary sequence generation algorithm can be combined with a separately proposed symmetric key agreement protocol to provide usable security for communications in Wireless Body Area Networks (WBAN). Other previous works in this area fall short by only considering key generation between two of the same signals or allowing for key generation between two different types of signals but with the cost of a significant signal collection time requirement. We hoped to advance this area of research by making secure key generation more efficient with less signal collection time and allowing keys to be generated between two sensors that measure two different physiological signals. However, while the binary sequence generation algorithm and key agreement protocol perform well separately, they do not perform well together. The combined approach yields keys that have good properties for use in a WBAN, but the generation rate is low.
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Naik, Vinayak Shashikant. „Reliable and secure data transport in large scale wireless networks of embedded devices“. Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1154092710.
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Zeraatzade, Mahbube. „Transmission congestion management by optimal placement of FACTS devices“. Thesis, Brunel University, 2010. http://bura.brunel.ac.uk/handle/2438/4710.
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This thesis describes the implementation of the Flexible AC Transmission Systems (FACTS) devices to develop a market-based approach to the problem of transmission congestion management in a Balancing Market. The causes, remedies and pricing methods of transmission congestion are briefly reviewed. Balancing Market exists in markets in which most of the trading is done via decentralized bilateral contracts. In these markets only final adjustments necessary to ensure secure system operation is carried out at a centralized Balancing Market. Each market player can participate in the Balancing Market by submitting offers and bids to increase and decrease its initially submitted active generation output. In this research a method is proposed to reduce costs associated with congestion re-dispatch in a Balancing Market by optimal placement of FACTS devices, and in particular Thyristor Controlled Phase Shifter Transformers (TCPST). The proposed technique is applicable to both Mixed Integer Linear Programming (MILP) and Mixed Integer Non-Linear Programming (MINLP). In the MILP a power system network is represented by a simplified DC power flow under a MILP structure and the Market participants' offers and bids are also represented by linear models. Results show that applications of FACTS devices can significantly reduce costs of congestion re-dispatch. The application of the method based on the MINLP creates a nonlinear and non-convex AC OPF problem that might be trapped in local sub-optima solutions. The reliability of the solution that determines the optimal placement of FACTS devices is an important issue and is carried out by investigation of alternative solvers. The behavior of the MINLP solvers is presented and finally the best solvers for this particular optimization problem are introduced. The application of DC OPF is very common in industry. The accuracy of the DC OPF results is investigated and a comparison between the DC and AC OPF is presented.
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Hussain, Musharrif, und Sulman Mahmood. „Secure Software and Communication on Handheld Devices“. Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4348.
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Some applications on mobile handheld devices are involved in exchanging critical information e. g. sending positioning data of heavy-good vehicles as a basis for road toll. This information must not be accessed or modified illegitimately; however, there is the risk that can be accessed or modified by modifying the application or during communication of the handheld device with its counterpart. This thesis report investigates concepts to shelter software from modification and how the communication of these applications running on a handheld device over public mobile network can be made more secure. This work was performed by carefully identifying relevant literature and developing the concept that how a smart card can enhance the security of the software running on it particularly for handheld devices. It also discusses the issues and threats to smart cards. Furthermore it proposes a solution based on the specified scenario. The security of the software comprises on two layers; one layer is for analysis prevention, making it hard to understand the behaviour of the program both at static and dynamic levels. The other layer is responsible for verifying the integrity of the software to ensure that it is not modified. The software is installed on smart card which acts as an extra security layer. The communication relies on the security features of the public mobile network with some enhancement. In order to shelter the communication via public Internet, a border based VPN solution is deployed between the public mobile network and the remote server using the network assisted approach. This thesis will serve as basis for designing a secure communication path for Swedish road toll system.Some applications on mobile handheld devices are involved in exchanging critical information e. g. sending positioning data of heavy-good vehicles as a basis for road toll. This information must not be accessed or modified illegitimately; however, there is the risk that can be accessed or modified by modifying the application or during communication of the handheld device with its counterpart. This thesis report investigates concepts to shelter software from modification and how the communication of these applications running on a handheld device over public mobile network can be made more secure. This work was performed by carefully identifying relevant literature and developing the concept that how a smart card can enhance the security of the software running on it particularly for handheld devices. It also discusses the issues and threats to smart cards. Furthermore it proposes a solution based on the specified scenario. The security of the software comprises on two layers; one layer is for analysis prevention, making it hard to understand the behaviour of the program both at static and dynamic levels. The other layer is responsible for verifying the integrity of the software to ensure that it is not modified. The software is installed on smart card which acts as an extra security layer. The communication relies on the security features of the public mobile network with some enhancement. In order to shelter the communication via public Internet, a border based VPN solution is deployed between the public mobile network and the remote server using the network assisted approach. This thesis will serve as basis for designing a secure communication path for Swedish road toll system.
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Rossland, Lindvall Caspar, und Mikael Söderberg. „Efficient naming for Smart Home devices in Information Centric Networks“. Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-424259.
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The current network trends point towards a significant discrepancy between the data usage and the underlying architecture; a severely increasing amount of data is being sent from more devices while data usage is becoming more data-centric instead of the previously host-centric. Information Centric Network (ICN) is a new alternative network paradigm that is designed for a data-centric usage. ICN is based on uniquely naming data packages and making it location independent. This thesis researched how to implement an efficient naming for ICN in a Smart Home Scenario. The results are based on testing how the forwarding information base is populated for numerous different scenarios and how a node's duty cycle affects its power usage. The results indicate that a hierarchical naming is optimized for hierarchical-like network topology and a flat naming for interconnected network topologies. An optimized duty cycle is strongly dependent on the specific network and accordingto the results can a sub-optimal duty cycle lead to excessive powerusage.
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Norman, Kelly Robert. „Encryption of Computer Peripheral Devices“. Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1232.pdf.
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Keeney, Jacquelyn Nicole. „Evaluation of the Repeatability and Reproducibility of Network-Level Pavement Macrotexture Measuring Devices“. Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78721.
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The purpose of this thesis was to assess the repeatability and reproducibility of two high-speed macrotexture measuring systems. The first portion of the study collected macrotexture measurements using the two high-speed systems on the Virginia Smart Road facility and validated the reproducibility of the mean profile depth (MPD) measurements with reference CT Meter measurements. The various data sets were then compared with each other. The objective was to determine whether the two systems are collecting repeatable and reproducible data.
The analysis showed that the two high-speed systems investigated have good repeatability (0.105 mm for the Ames and 0.113 mm for the SCRIM) when measuring the average MPD of the sections investigated. The two systems produce measurements that are highly-correlated (Ames R2 = 0.9591 and SCRIM R2 = 0.9157) with the reference ones obtained with the CT Meter. While the Ames systems, with the data processed using the Virginia Tech filter, measures MPD values that are very close to those of the CT Meter, with a virtually zero systematic bias. The SCRIM obtains slightly lower readings. The differences are thought to be due to the filtering of the raw pavement elevation measurements used by the SCRIM processing software to eliminate dropout and spikes in the laser measurements.Master of Science