Dissertations / Theses: 'Operating Systems'

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Clarke, Reginald. "College operating systems." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340657.

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Martlew, P. J. "Microcomputer process operating systems." Thesis, Swansea University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638017.

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A chemical process plant control software support system aimed at simplifying the task of designing and implementing complete digital computer chemical plant control systems was designed, and partially implemented on an 8-bit microcomputer. The bulk of the system (excluding the program development environment) was designed and fully specified, as was the application programming language. The system was designed with the aim of reducing the number of faults present in a finished application system. Consequently ease of use, conceptual simplicity, flexibility and reliability were its main design goals. The system was broken into two major components. These were the software support system and the application programming system. The software support system provided a mechanism to fully configure the system structure to match that of the controlled plant, a comprehensive menu driven operator interface, and a run-time execution control environment. The application programming system comprised a module interface type application language with message based inter-module communication and a very high level event and data interface to the controlled system. The application programming language compiler and editor were not implemented, due to the constraints imposed by project timescales. The attached appendices contain full details of the design and implementation work carried out, whilst the thesis itself illustrates the more general issues which underlie the system design.

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Pinnix, Justin Everett. "Operating System Kernel for All Real Time Systems." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20010310-181302.

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PINNIX, JUSTIN EVERETT. Operating System Kernel for All Real Time Systems.(Under the direction of Robert J. Fornaro and Vicki E. Jones.)

This document describes the requirements, design, and implementation of OSKAR, ahard real time operating system for Intel Pentium compatible personal computers.OSKAR provides rate monotonic scheduling, fixed and dynamic priority scheduling,semaphores, message passing, priority ceiling protocols, TCP/IP networking, and globaltime synchronization using the Global Positioning System (GPS). It is intended toprovide researchers a test bed for real time projects that is inexpensive, simple tounderstand, and easy to extend.

The design of the system is described with special emphasis on design tradeoffs made toimprove real time requirements compliance. The implementation is covered in detail atthe source code level. Experiments to qualify functionality and obtain performanceprofiles are included and the results explained.

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Baumann, Andrew Computer Science &amp Engineering Faculty of Engineering UNSW. "Dynamic update for operating systems." Awarded by:University of New South Wales. Computer Science and Engineering, 2007. http://handle.unsw.edu.au/1959.4/28356.

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Patches to modern operating systems, including bug fixes and security updates, and the reboots and downtime they require, cause tremendous problems for system users and administrators. The aim of this research is to develop a model for dynamic update of operating systems, allowing a system to be patched without the need for a reboot or other service interruption. In this work, a model for dynamic update based on operating system modularity is developed and evaluated using a prototype implementation for the K42 operating system. The prototype is able to update kernel code and data structures, even when the interfaces between kernel modules change. When applying an update, at no point is the system's entire execution blocked, and there is no additional overhead after an update has been applied. The base runtime overhead is also very low. An analysis of the K42 revision history shows that approximately 79% of past performance and bug-fix changes to K42 could be converted to dynamic updates, and the proportion would be even higher if the changes were being developed for dynamic update. The model also extends to other systems such as Linux and BSD, that although structured modularly, are not strictly object-oriented like K42. The experience with this approach shows that dynamic update for operating systems is feasible given a sufficiently-modular system structure, allows maintenance patches and updates to be applied without disruption, and need not constrain system performance.

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O'Shea, Gregory Francis Gerard. "Access control in operating systems." Thesis, Birkbeck (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301025.

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Moura, F. C. S. "Performance evaluation of operating systems." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374799.

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Tomiyama, Hiroyuki, Shinya Honda, and Hiroaki Takada. "Real-Time Operating Systems for Multicore Embedded Systems." IEEE, 2008. http://hdl.handle.net/2237/12100.

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Oakes, David R. "Microsoft operating systems development and strategy : an assessment of the Windows 2000 Server operating system." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA369436.

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Thesis (M.S. in Systems Technology (Scientific and Technical Intelligence)) Naval Postgraduate School, September 1999.
Thesis advisor(s): Douglas E. Brinkley. Includes bibliographical references (p. 151-153). Also Available online.

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Mack, Raphael. "Modeling and verifying embedded operating systems." Zürich : ETH, Eidgenössische Technische Hochschule Zürich, Institut für Computersysteme, 2008. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=367.

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Aigner, Ronald. "Communication in Microkernel-Based Operating Systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-68373.

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Communication in microkernel-based systems is much more frequent than system calls known from monolithic kernels. This can be attributed to the placement of system services into their own protection domains. Communication has to be fast to avoid unnecessary overhead. Also, communication channels in microkernel-based systems are used for more than just remote procedure calls. In distributed systems, which also have a componentized design, it is state of the art to use tools to generate stubs for the communication between components. The communication interfaces of components are described in an interface definition language (IDL). In contrast to distributed systems, components of a microkernel-based system run on the same architecture and message delivery is guaranteed. In this Thesis, I explore the different kinds of communication, which can be used in microkernel-based systems, as well as their possible representation in IDL. Specifically, I introduce the syntax to describe kernel objects in IDL. I discuss the complexity of IDL compilers and its relation to the complexity of the IDL. Furthermore, I evaluate the performance of the communication stubs generated by different IDL compilers and discuss techniques to minimize performance overhead in generated stubs. I validated these techniques by implementing the Drops IDL Compiler - Dice. Finally, this Thesis presents a mechanism to measure the frequency and performance of invocations of generated communication code. I used this technique to conduct measurements in highly complex systems and introducing the least possible overhead.

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Coltzau, Hauke, and Herwig Unger. "3DIOS1 – Konzept eines Internet-Operating-Systems." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-141688.

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Es wird ein Konzept für ein zukünftiges Betriebssystem vorgestellt, das den Anforderungen und Möglichkeiten der zunehmenden Vernetzung von Rechnern und anderen Endgeräten Rechnung trägt. Es erweitert den bekannten Grundgedanken, mit Hilfe von Peer-to-Peer Technologien explorierbare virtuelle 3D-Landschaften zu erzeugen, ohne dabei von einem zentralen Anbieter abhängig zu sein. Es soll Nutzern die Möglichkeit bieten, das Serviceangebot im Internet ohne Einschränkungen zu durchsuchen und dabei anhand eigener semantischer Kriterien die für sie interessanten Services hervorzuheben. Über Parameter der Darstellung sollen Netzwerkeigenschaften, die für den Nutzer von Belang sein können, intuitiv erfassbar sein. Das System beinhaltet darüber hinaus Möglichkeiten zur Last- und Verkehrsbalancierung. In diesem Artikel werden Anforderungen an die zu Grunde liegende Infrastruktur und die grafische Benutzeroberfläche definiert, erste Skizzen des zukünftigen Systems vorgestellt und die weiteren Schritte bis zur Verwirklichung eines Prototyps diskutiert.

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Neugebauer, Rolf. "Decentralising resource management in operating systems." Thesis, University of Glasgow, 2003. http://theses.gla.ac.uk/4118/.

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This dissertation explores operating system mechanisms to allow resource-aware applications to be involved in the process of managing resources under the premise that these applications (1) potentially have some (implicit) notion of their future resource demands and (2) can adapt their resource demands. The general idea is to provide feedback to resource-aware applications so that they can proactively participate in the management of resources. This approach has the benefit that resource management policies can be removed from central entities and the operating system has only to provide mechanism. Furthermore, in contrast to centralised approaches, application specific features can be more easily exploited. To achieve this aim, I propose to deploy a microeconomic theory, namely congestion or shadow pricing, which has recently received attention for managing congestion in communication networks. Applications are charged based on the potential "damage" they cause to other consumers by using resources. Consumers interpret these congestion charges as feedback signals which they use to adjust their resource consumption. It can be shown theoretically that such a system with consumers merely acting in their own self-interest will converge to a social optimum. This dissertation focuses on the operating system mechanisms required to decentralise resource management this way. In particular it identifies four mechanisms: pricing & charging, credit accounting, resource usage accounting, and multiplexing. While the latter two are mechanisms generally required for the accurate management of resources, pricing & charging and credit accounting present novel mechanisms. It is argued that congestion prices are the correct economic model in this context and provide appropriate feedback to applications. The credit accounting mechanism is necessary to ensure the overall stability of the system by assigning value to credits.

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Stuber, Matthew David. "Evaluation of process systems operating envelopes." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/79143.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2013.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 229-238).
This thesis addresses the problem of worst-case steady-state design of process systems under uncertainty, also known as robust design. Designing for the worst case is of great importance when considering systems for deployment in extreme and hostile environments, where operational failures cannot be risked due to extraordinarily high economic and/or environmental expense. For this unique scenario, the cost of "over-designing" the process far outweighs the cost associated with operational failure. Hence, it must be guaranteed that the process is sufficiently robust in order to avoid operational failures. Many engineering, economic, and operations research applications are concerned with worst-case scenarios. Classically, these problems give rise to a type of leader-follower game, or Stackelberg game, commonly known as the "minimax" problem, or more precisely as a max-min or min-max optimization problem. However, since the application here is to steady-state design, the problem formulation results in a more general nonconvex equality-constrained min-max program, for which no previously available algorithm can solve effectively. Under certain assumptions, the equality constraints, which correspond to the steady-state model, can be eliminated from the problem by solving them for the state variables as implicit functions of the control variables and uncertainty parameters. This approach eliminates explicit functional dependence on the state variables, and in turn reduces the dimensionality of the original problem. However, this embeds implicit functions in the program, which have no explicit algebraic form and can only be approximated using numerical methods. By doing this, the max-min program can be reformulated as a more computationally tractable semi-infinite program, with the caveat that there are embedded implicit functions. Semi-infinite programming with embedded implicit functions is a new approach to modeling worst-case design problems. Furthermore, modeling process systems--especially those associated with chemical engineering--often results in highly nonconvex functions. The primary contribution of this thesis is a mathematical tool for solving implicit semi-infinite programs and assessing robust feasibility of process systems using a rigorous model-based approach. This tool has the ability to determine, with mathematical certainty, whether or not a physical process system based on the proposed design will fail in the worst case by taking into account uncertainty in the model parameters and uncertainty in the environment.
by Matthew David Stuber.
Ph.D.

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Sinha, Amit 1976. "Energy efficient operating systems and software." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86773.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.
Includes bibliographical references (p. 153-159).
Energy efficient system design is becoming increasingly important with the proliferation of portable, battery-operated appliances such as laptops, Personal Digital Assistants (PDAs) and cellular phones. Numerous dedicated hardware approaches for energy mini-mization have been proposed while software energy efficiency has been relatively unexplored. Since it is the software that drives the hardware, decisions taken during software design can have a significant impact on system energy consumption. This thesis explores avenues for improving system energy efficiency from application level to the operating system level. The embedded operating system can have a significant impact on system energy by performing dynamic power management both in the active and passive states of the device. Software controlled active power management techniques using dynamic voltage and frequency scaling have been explored. Efficient workload prediction strategies have been developed that enable just-in-time computation. An algorithm for efficient real-time operating system task scheduling has also been developed that minimizes energy consumption. Portable systems spend a lot of time in sleep mode. Idle power management strategies have been developed that consider the effect of leakage and duty-cycle on system lifetime. A hierarchical shutdown approach for systems characterized multiple sleep states has been proposed. Although the proposed techniques are quite general, their applicability and utility have been demonstrated using the MIT [mu]AMPS wireless sensor node an example system wherever possible.
(cont.) To quantify software energy consumption, an estimation framework has been developed based on experiments on the StrongARM and Hitachi processors. The software energy profiling tool is available on-line. Finally, in energy constrained systems, we would like to have the ability to trade-off quality of service for extended battery life. A scalable approach to application development has been demonstrated that allows energy quality trade-offs.
by Amit Sinha.
Ph.D.

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Coltzau, Hauke, and Herwig Unger. "3DIOS1 – Konzept eines Internet-Operating-Systems." Technische Universität Dresden, 2009. https://tud.qucosa.de/id/qucosa%3A27977.

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Es wird ein Konzept für ein zukünftiges Betriebssystem vorgestellt, das den Anforderungen und Möglichkeiten der zunehmenden Vernetzung von Rechnern und anderen Endgeräten Rechnung trägt. Es erweitert den bekannten Grundgedanken, mit Hilfe von Peer-to-Peer Technologien explorierbare virtuelle 3D-Landschaften zu erzeugen, ohne dabei von einem zentralen Anbieter abhängig zu sein. Es soll Nutzern die Möglichkeit bieten, das Serviceangebot im Internet ohne Einschränkungen zu durchsuchen und dabei anhand eigener semantischer Kriterien die für sie interessanten Services hervorzuheben. Über Parameter der Darstellung sollen Netzwerkeigenschaften, die für den Nutzer von Belang sein können, intuitiv erfassbar sein. Das System beinhaltet darüber hinaus Möglichkeiten zur Last- und Verkehrsbalancierung. In diesem Artikel werden Anforderungen an die zu Grunde liegende Infrastruktur und die grafische Benutzeroberfläche definiert, erste Skizzen des zukünftigen Systems vorgestellt und die weiteren Schritte bis zur Verwirklichung eines Prototyps diskutiert.

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Caiazza, Gianluca <1991&gt. "Security Enhancements of Robot Operating Systems." Master's Degree Thesis, Università Ca' Foscari Venezia, 2017. http://hdl.handle.net/10579/10238.

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In recent years we observed a grown of cybersecurity threats, especially thanks to the ubiquitous of connected and autonomous devices. A list of these devices, commonly defined as Internet of Things, includes industrial automation, autonomous vehicles, robot-assisted surgery, surveillance platforms, home service automation and many more robotics domains; considering the sensitive information that are processed by these devices, the possibility of attacks should be considered as a serious security matter. This thesis focuses on the Robot Operating System (ROS), a widely adopted standard robotic middle-ware. We will analyse its possible vulnerabilities and the resulting threats that could be posed by attackers. More in details, the present work will provide an in-depth analysis of ROS and SROS - a proposed addition to the ROS API ecosystem to support modern cryptography and security measures - in addition to the development of a static analyser upon SROS for the automatic creation of software-enforcement security profiles. In order to do so, we performed the following tasks: (1) standardize the security logging format; (2) standardize the profile syntax for the policy; (3) provide new tooling to introspect recorded security logs. Lastly, we discussed some enhancements for SROS following the standard proposed by oneM2M.

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Watson, Robert Nicholas Maxwell. "New approaches to operating system security extensibility." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609485.

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Craft, Timothy L. "The systems engineering design of a smart Forward Operating Base surveillance system for forward operating base protection." Monterey, California: Naval Postgraduate School, 2013. http://hdl.handle.net/10945/34650.

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Approved for public release; distribution is unlimited
Forward operating bases are vulnerable to terrorist activity due to their location and limited resources. Threat awareness under these conditions is paramount to the safety of the personnel and to mission accomplishment. In the absence of the manpower required to maintain complete and continuous monitoring of the FOBs surroundings, an automated surveillance system is needed. The Smart FOB Surveillance System (SFSS) employs a multi-agent behavior analysis and decision system with Swarm Intelligence (SI) through a network-centric systems engineering method of development to create a robust surveillance system. The SFSS provides the capability of an intelligence automated system for continuously monitoring areas for certain behaviors, linking individuals, predicting future behaviors, and taking appropriate action against them to eliminate threats and the possibility of future threats. Environments, such as insurgent urban areas, Forward Operating Bases, country borders, and other high-value target areas all require constant personnel behavior surveillance and monitoring. The SFSS utilizes a complex network of aerial, fixed and mobile terrestrial units, capable of identifying and processing audible, visual, and signal intelligence in order to determine personnel behavior in a given area of interest as well as recording and processing intelligence data. The focus is on creating a system to protect Forward Operating Bases (FOB) by providing continuous and autonomous surveillance and threat alerts. In this manner, a Smart FOB Surveillance System (SFSS) will be designed in this thesis using the systems engineering process.

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Wei, Jinpeng. "Improving operating systems security two case studies /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31849.

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Thesis (Ph.D)--Computing, Georgia Institute of Technology, 2010.
Committee Chair: Pu, Calton; Committee Member: Ahamad, Mustaque; Committee Member: Blough, Douglas; Committee Member: Giffin, Jonathon; Committee Member: Li, Kang. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Frame, Charles E. "Personal computer and workstation operating systems tutorial." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA280132.

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Thesis (M.S. in Information Technology Management) Naval Postgraduate School, March 1994.
Thesis advisor(s): Norman F. Schneidewind. "March 1994." Includes bibliographical references. Also available online.

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Swift, Michael M. "Improving the reliability of commodity operating systems /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/7019.

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Denz, Robert. "Securing Operating Systems Through Utility Virtual Machines." Thesis, Dartmouth College, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10190644.

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The advent of hypervisors revolutionized the computing industry in terms of malware prevention and detection, secure virtual machine managers, and cloud resilience. However, this has resulted in a disjointed response to handling known threats rather than preventing unknown zero-day threats. This thesis introduces a new paradigm to cloud computing – utility virtual machines – that directly leverages virtualization hardware for protection and eliminates often accepted roles of the operating system kernel. This represents a break from prevailing practices and serves to establish a hardware root of trust for system operation.

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Fotuhi-Firuzabad, Mahmud. "Operating health analysis of electric power systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0012/NQ27407.pdf.

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Kazakidis, Vassilios N. "Operating risk, planning for flexible mining systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ61126.pdf.

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Westman, Patrik. "Debugging methods - applied on networking operating systems." Thesis, Umeå universitet, Institutionen för datavetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-81115.

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As the computer hardware has become more powerful the parallel and distributed programming has become increasingly popular. The debugging of these systems are however complex. It is common that when debugging such systems only print-statements are used since debugging environments may be hard, or impossible to run on the target systems.The aim of this thesis is to provide an understanding of debugger architecture and the most commonly used debugging techniques and where these are used. This will not give a complete understanding of them, but hopefully questions will be raised that may aid users to expand their debugging operations and question the techniques that they use.Some of these debugging techniques will be applied to give suggestion of a method which allow debugging of systems with several processes where dependencies between the processes are high. This method is presented in chapter 4 and involves a remote debugging solution using the GDB debugger as a back-end debugger.

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Jannotti, John 1974. "Applying exokernel principles to conventional operating systems." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50043.

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DeBrunner, Linda Sumners. "Multitasking operating systems for real-time applications." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/104318.

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Crawley, P. D. "Optimum operating policies for multiple reservoir systems /." Title page, contents and synopsis only, 1990. http://web4.library.adelaide.edu.au/theses/09EN/09enc911.pdf.

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Lescouet, Alexis. "Memory management for operating systems and runtimes." Electronic Thesis or Diss., Institut polytechnique de Paris, 2021. http://www.theses.fr/2021IPPAS008.

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Avec l'émergence et l'évolution rapide de domaines scientifiques tels que l'analyse de données ou l'intelligence artificielle, les besoins en puissance de calcul ont fortement augmenté. Depuis des années, en raison de contraintes physiques, l'augmentation de la puissance des processeurs se fait au travers d'une augmentation du nombre de cœurs et non plus d'une augmentation de la fréquence. Ce nouveau paradigme nécessite une évolution du logiciel afin de pouvoir développer toute la puissance de ces machines, faisant ainsi du parallélisme une pierre angulaire de la pile logicielle. Les systèmes d'exploitation, directement concernés, doivent inclure différentes règles permettant la bonne gestion de différents types de machines. Cependant, la gestion de ressources est souvent divisée en différentes unités responsables chacune d'une ressource spécifique, qui prennent des décisions sans vision globale du système. De plus, en raison de la complexité et de l'évolution rapide du matériel, les systèmes d'exploitation ont de plus en plus de difficultés à tenir compte des variations subtiles entre deux machines. L'important développement de la technologie de virtualisation nous permet de proposer une nouvelle approche pour la gestion de ressources qui utilise la virtualisation pour ajouter une couche de gestion des ressources dédiée entre la machine et le système d'exploitation habituel. Au même titre que les systèmes d'exploitation, les applications doivent exécuter une partie de leur code en parallèle pour obtenir des performances élevées. C'est le cas en particulier pour les environnements d'exécution tels que MPI qui ont pour but d'aider à la parallélisation d'applications. Avec les architectures matérielles modernes dotées de réseaux rapides, le recouvrement de la communication réseau avec du calcul est devenu partie intégrante du parallélisme applicatif. Une certaine quantité de recouvrement peut être obtenue manuellement mais cela reste une procédure complexe. Notre approche propose de transformer automatiquement les communications bloquantes en communications non bloquantes, augmentant ainsi le potentiel de recouvrement. Pour cela, nous utilisons un thread séparé pour les communications et contrôlons les accès à la mémoire des communications. Nous garantissons ainsi la progression des communications et une meilleure parallélisation de celles-ci et des calculs
During the last decade, the need for computational power has increased due to the emergence and fast evolution of fields such as data analysis or artificial intelligence. This tendency is also reinforced by the growing number of services and end-user devices. Due to physical constraints, the trend for new hardware has shifted from an increase in processor frequency to an increase in the number of cores per machine. This new paradigm requires software to adapt, making the ability to manage such a parallelism the cornerstone of many parts of the software stack. Directly concerned by this change, operating systems have evolved to include complex rules each pertaining to different hardware configurations. However, more often than not, resources management units are responsible for one specific resource and make a decision in isolation. Moreover, because of the complexity and fast evolution rate of hardware, operating systems, not designed to use a generic approach have trouble keeping up. Given the advance of virtualization technology, we propose a new approach to resource management in complex topologies using virtualization to add a small software layer dedicated to resources placement in between the hardware and a standard operating system. Similarly, in user space applications, parallelism is an important lever to attain high performances, which is why high performance computing runtimes, such as MPI, are built to increase parallelism in applications. The recent changes in modern architectures combined with fast networks have made overlapping CPU-bound computation and network communication a key part of parallel applications. While some degree of overlap might be attained manually, this is often a complex and error prone procedure. Our proposal automatically transforms blocking communications into non blocking ones to increase the overlapping potential. To this end, we use a separate communication thread responsible for handling communications and a memory protection mechanism to track memory accesses in communication buffers. This guarantees both progress for these communications and the largest window during which communication and computation can be processed in parallel

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Pettersson, Erik. "Comparison of System Performance During DDoS Attacks in Modern Operating Systems." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-13748.

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Distributed Denial of Service attacks are an ever prevalent challenge for system administra-tors today to overcome. The attack, which is all about restricting legitimate users access to a service, such as a web-page. Can cost companies and governments millions of dollars if not properly managed. This study aims to explore if there is any difference in performance between some of the most modern iterations of popular server operating systems today. Those server operating systems are: Windows Server 2016, Ubuntu 16 and FreeBSD 11. And submitting them to one of the most popular DDoS attacks at the time of writing, a so called HTTP-Get request. The webservers used are some of the most widely used today, Apache and Microsoft IIS. Each server will be submitted to attacks, and compared between one another. Different de-fence methods will also be tested and examined. Tests include shorter tests that is repeated multiple times for data validity, and one longer test for every condition in order to control if the results are similar. During these tests, the operating systems will measure CPU/RAM utilization, and a control computer will measure Round Trip Time. Windows Server 2016 using IIS and FreeBSD 11 perform similarly resource wise, but Win-dows Server 2016 with IIS had a better Round Trip Time performance. Windows Server 2016 with Apache performs worst in all measurements, while Ubuntu 16 performs in the middle, but has the most stable performance.

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Woolard, C. C. "A network object oriented operating system." Thesis, University of Essex, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381930.

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Grossman, Michael D. "A computer simulation of processor scheduling in UNIX 4.2BSD /." Online version of thesis, 1987. http://hdl.handle.net/1850/10295.

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Goel, Ashvin. "Operating system support for low-latency streaming /." Full text open access at:, 2003. http://content.ohsu.edu/u?/etd,194.

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Wang, Xiaolong. "A Secure Computing Platform for Building Automation Using Microkernel-based Operating Systems." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7589.

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Building Automation System (BAS) is a complex distributed control system that is widely deployed in commercial, residential, industrial buildings for monitoring and controlling mechanical/electrical equipment. Through increasing industrial and technological advances, the control components of BAS are becoming increasingly interconnected. Along with potential benefits, integration also introduces new attack vectors, which tremendous increases safety and security risks in the control system. Historically, BAS lacks security design and relies on physical isolation and "security through obscurity". These methods are unacceptable with the "smart building" technologies. The industry needs to reevaluate the safety and security of the current building automation system, and design a comprehensive solution to provide integrity, reliability, and confidentiality on both system and network levels. This dissertation focuses on the system level in the effort to provide a reliable computing foundation for the devices and controllers. Leveraged on the preferred security features such as, robust modular design, small privilege code, and formal verifiability of microkernel architecture, this work describes a security enhanced operating system with built-in mandatory access control and a proxy-based communication framework for building automation controllers. This solution ensures policy-enforced communication and isolation between critical applications and non-critical applications in a potentially hostile cyber environment.

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Larsson, Anders. "Fully automatic benchmarking of real-time operating systems." Thesis, University of Skövde, Department of Computer Science, 1998. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-172.

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Testing and evaluating the performance of different software solutions is important in order to compare them with each other. Measuring, or benchmark, software is not a trivial task and conducting tests in a real-time environment implicates it further. Still, measuring is the only way to provide useful information, for example, which real-time operating system is best suitable for a specific hardware configuration.

The purpose of this project is to design a benchmark support system, which automatically performs benchmarks of a real-time operating system in a host-target environment. The benchmarks are conducted according to a user-defined specification and the support system also allows a developer to create configurable benchmarks.

The benchmark support system described also allows parameters to increase monotonically within a specified interval during benchmark execution. This is an important feature in order to detect unpredictable behavior of the real-time system.

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Bagikni, Tarek al. "Developing an autonomic system engineering testbed using virtualization virtualization of operating systems." Saarbrücken VDM, Müller, 2007. http://d-nb.info/986348104/04.

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Snowdon, David Computer Science &amp Engineering Faculty of Engineering UNSW. "Operating system directed power management." Awarded By:University of New South Wales. Computer Science & Engineering, 2010. http://handle.unsw.edu.au/1959.4/44747.

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Energy is a critical resource in all types of computing systems from servers, where energy costs dominate data centre expenses and carbon footprints, to embedded systems, where the system's battery life limits the device's functionality. In their efforts to reduce the energy use of these system's hardware manufacturers have implemented features which allow a reduced energy consumption under software control. This thesis shows that managing these settings is a more complex problem than previously considered. Where much (but not all) of the previous academic research investigates unrealistic scenarios, this thesis presents a solution to managing the power on varying hardware. Instead of making unrealistic assumptions, we extract a model from empirical data and characterise that model. Our models estimate the effect of different power management settings on the behaviour of the hardware platform, taking into account the workload, platform and environmental characteristics, but without any kind of a-priori knowledge of the specific workloads being run. These models encapsulate a system's knowledge of the platform. We also developed a \emph{generalised energy-delay} policy which allows us to quickly express the instantaneous importance of both performance and energy to the system. It allows us to select a power management strategy from a number of options. This thesis shows, by evaluation on a number of platforms, that our implementation, Koala, can accurately meet energy and performance goals. In some cases, our system saves 26\% of the system-level energy required for a task, while losing only 1\% performance. This is nearly 46\% of the dynamic energy. Taking advantage of all energy-saving opportunities requires detailed platform, workload and environmental information. Given this knowledge, we reach the exciting conclusion that near optimal power management is possible on real operating systems, with real platforms and real workloads.

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Szyperski, Clemens A. "Insight Ethos : on object-orientation in operating systems /." Zürich : Verlag der Fachvereine an den schweizerischen Hochschulen und Techniken, 1992. http://opac.nebis.ch/cgi-bin/showAbstract.pl?u20=3728119482.

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Dodge, Catherine A. "Recommendations for secure initialization routines in operating systems /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FDodge.pdf.

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Thesis (M.S. in Computer Science)--Naval Postgraduate School, December 2004.
Thesis Advisor(s): Cynthia E. Irvine, Thuy D. Nguyen. Includes bibliographical references (p. 107-109) Also available online.

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MORENO, MARCELO FERREIRA. "A FRAMEWORK FOR QOS PROVISIONING IN OPERATING SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=3341@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
A demanda progressiva por aplicações multimídia distribuídas, caracterizadas por fortes exigências sobre os recursos computacionais, torna evidente a necessidade de provisão de qualidade de serviço (QoS) em cada um dos subsistemas envolvidos, como redes de comunicação e sistemas operacionais. Ao mesmo tempo, tais subsistemas devem ser flexíveis para que possam oferecer novos serviços a aplicações futuras, ou seja, devem ser adaptáveis em tempo de execução. Especificamente, sistemas operacionais de uso geral provêm pouco ou nenhum suporte a QoS e à adaptabilidade dos serviços, impulsionando vários estudos isolados nessas áreas. Observando-se algumas tecnologias implementadas em sistemas operacionais específicos, nota-se que os mecanismos de provisão possuem certas semelhanças funcionais. Assim, este trabalho propõe uma arquitetura adaptável para a provisão de QoS nos subsistemas de rede e de escalonamento de processos de sistemas operacionais, independente de implementação, através da descrição de frameworks genéricos. É demonstrado, também, como os pontos de flexibilização desses frameworks podem ser especializados para a implementação de alguns modelos de QoS. Por último, é proposto um cenário de uso da arquitetura, no qual um sistema operacional de uso geral ligeiramente modificado é utilizado como infra- estrutura para a instanciação dos frameworks de QoS.
The progressive demand for distributed multimedia applications, which are characterized by strong requirements over computational resources, makes evident the need for quality of service (QoS) provisioning in each one of the involved subsystems (e.g. communication networks and operating systems). At the same time, these subsystems must be flexible enough that they can offer new services to future applications, or in other words, they must be adaptable at runtime. Specifically, general-purpose operating systems provide few or no QoS/service adaptability support, what have motivated many isolated studies about these topics. Observing some implemented technologies on specific operating systems,it is noted that the provisioning mechanisms have certain functional similarities.In this way, this work proposes an adaptable architecture for QoS provisioning on networking and process scheduling subsystems of operating systems, through the description of generic frameworks. It is demonstrated how the framework hot-spots can be specialized in order to implement some QoS models. Finally, it is proposed a scenario of use of the architecture, where a bit modified generalpurpose operating system is used as infrastructure for an instantiation of the QoS frameworks.

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Dodge, Catherine A. "Recommendations for secure initialization routines in operating systems." Thesis, Monterey, California. Naval Postgraduate School, 2004. http://hdl.handle.net/10945/1206.

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Approved for public release; distribution in unlimited.
While a necessity of all operating systems, the code that initializes a system can be notoriously difficult to understand. This thesis explores the most common architectures used for bringing an operating system to its initial state, once the operating system gains control from the boot loader. Specifically, the ways in which the OpenBSD and Linux operating systems handle initialization are dissected. With this understanding, a set of threats relevant to the initialization sequence was developed. A thorough study was also made to determine the degree to which initialization code adheres to widely accepted software engineering principles. Based upon this threat analysis and the observed strengths and weaknesses of existing systems, a set of recommendations for initialization sequence architecture and implementation have been developed. These recommendations can serve as a guide for future operating system development.
Civilian, Naval Postgraduate School

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Roth, Christopher. "A distributed password scheme for network operating systems." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Jun%5FRoth.pdf.

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Leslie, Rebekah. "A Functional Approach to Memory-Safe Operating Systems." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/499.

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Purely functional languages--with static type systems and dynamic memory management using garbage collection--are a known tool for helping programmers to reduce the number of memory errors in programs. By using such languages, we can establish correctness properties relating to memory-safety through our choice of implementation language alone. Unfortunately, the language characteristics that make purely functional languages safe also make them more difficult to apply in a low-level domain like operating systems construction. The low-level features that support the kinds of hardware manipulations required by operating systems are not typically available in memory-safe languages with garbage collection. Those that are provided may have the ability to violate memory- and type-safety, destroying the guarantees that motivate using such languages in the first place. This work demonstrates that it is possible to bridge the gap between the requirements of operating system implementations and the features of purely functional languages without sacrificing type- and memory-safety. In particular, we show that this can be achieved by isolating the potentially unsafe memory operations required by operating systems in an abstraction layer that is well integrated with a purely functional language. The salient features of this abstraction layer are that the operations it exposes are memory-safe and yet sufficiently expressive to support the implementation of realistic operating systems. The abstraction layer enables systems programmers to perform all of the low-level tasks necessary in an OS implementation, such as manipulating an MMU and executing user-level programs, without compromising the static memory-safety guarantees of programming in a purely functional language. A specific contribution of this work is an analysis of memory-safety for the abstraction layer by formalizing a meaning for memory-safety in the presence of virtual-memory using a novel application of noninterference security policies. In addition, we evaluate the expressiveness of the abstraction layer by implementing the L4 microkernel API, which has a flexible set of virtual memory management operations.

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Sjöström, Thames Sixten. "Porting a Real-Time Operating System to a Multicore Platform." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76933.

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This thesis is part of the European MANY project. The goal of MANY is to provide developers with tools to develop software for multi and many-core hardware platforms. This is the first thesis that is part of MANY at Enea. The thesis aims to provide a knowledge base about software on many-core at the Enea student research group. More than just providing a knowledge base, a part of the thesis is also to port Enea's operating system OSE to Tilera's many-core processor TILEpro64. The thesis shall also investigate the memory hierarchy and interconnection network of the Tilera processor. The knowledge base about software on many-core was constrained to investigating the shared memory model and operating systems for many-core. This was achieved by investigating prominent academic research about operating systems for many-core processors. The conclusion was that a shared memory model does not scale and for the operating system case, operating systems shall be designed with scalability as one of the most important requirements. This thesis has implemented the hardware abstraction layer required to execute a single-core version of OSE on the TILEpro architecture. This was done in three steps. The Tilera hardware and the OSE software platform were investigated. After that, an OSE target port was chosen as reference architecture. Finally, the hardware dependent parts of the reference software were modified. A foundation has been made for future development.

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Kluge, Florian [Verfasser], and Theo [Akademischer Betreuer] Ungerer. "Manycore Operating Systems for Safety-Critical Systems / Florian Kluge. Betreuer: Theo Ungerer." Augsburg : Universität Augsburg, 2016. http://d-nb.info/1111505438/34.

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Okyay, Mehmet Onur Aytaç Sıtkı. "A portable real-time operating system for embedded platforms/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/bilgisayaryazilimi/T000477.doc.

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Wells, George Clifford. "A study of real-time operating systems for microcomputers." Thesis, Rhodes University, 1990. http://hdl.handle.net/10962/d1004896.

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This thesis describes the evaluation of four operating systems for microcomputers. The emphasis of the study is on the suitability of the operating systems for use in real-time applications, such as process control. The evaluation was performed in two sections. The first section was a quantitative assessment of the performance of the real-time features of the operating system. This was performed using benchmarks. The criteria for the benchmarks and their design are discussed. The second section was a qualitative assessment of the suitability of the operating systems for the development and implementation of real-time systems. This was assessed through the implementation of a small simulation of a manufacturing process and its associated control system. The simulation was designed using the Ward and Mellor real-time design method which was extended to handle the special case of a real-time simulation. The operating systems which were selected for the study covered a spectrum from general purpose operating systems to small, specialised real-time operating systems. From the quantitative assessment it emerged that QNX (from Quantum Software Systems) had the best overall performance. Qualitatively, UNIX was found to offer the best system development environment, but it does not have the performance and the characteristics required for real-time applications. This suggests that versions of UNIX that are adapted for real-time applications are worth careful consideration for use both as development systems and implementation systems.

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Goktepe, Meftun. "Windows XP Operating System security analysis." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02sep%5FGoktepe.pdf.

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Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, September 2002.
Thesis advisor(s): Richard Harkins, Cynthia Irvine. Includes bibliographical references (p. 105-107). Also available online.

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Forbes, Harold C. "Operating system principles and constructs for dynamic multi-processor real-time control systems." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/8165.

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Biondi, Mattia. "An Updated Emulated Architecture to Support the Study of Operating Systems." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20751/.

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One of the most effective ways to learn something new is by actively practising it, and there is—maybe—no better way to study an Operating Systems course than by building your own OS. However, it is important to emphasize how the realization of an operating system capable of running on a real hardware machine could be an overly complex and unsuitable task for an undergraduate student. Nonetheless, it is possible to use a simplified computer system simulator to achieve the goal of teaching Computer Science foundations in the University environment, thus allowing students to experience a quite realistic representation of an operating system. µMPS has been created for this purpose, a pedagogically appropriate machine emulator, based around the MIPS R2/3000 microprocessor, which features an accessible architecture that includes a rich set of easily programmable devices. µMPS has an almost two decades old historical development and the outcome of this following thesis is the third version of the software, dubbed µMPS3. This second major revision aims to simplify, even more, the complexity of the emulator in order to lighten the load of work required by the students during the OS design and implementation. Two of these simplifications are the removal of the virtual memory bit, which allowed address translation to be turned on and off, and the replacement of the tape device, used as storage devices, with a new flash drive device—certainly something more familiar to the new generation of students. Thanks to the employment of this software and the feedback received over the last decade, it has been possible to realize not just this following thesis, but also to develop some major improvements, which concern everything from the project building tools to the front-end, making µMPS a modern and reliable educational software.

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Dissertations / Theses on the topic 'Operating Systems'

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