Thesis (M.S.C.I.T.)--Regis University, Denver, Colo., 2006. / Title from PDF title page (viewed on Aug. 30, 2006). Includes bibliographical references.

The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on November 13, 2009). Thesis advisor: Dr. Guilherme DeSouza. Includes bibliographical references.

Most interaction with computers today takes place in a two dimensional environment. Even when using three dimensional graphics applications, input is often still restricted to two dimensions. Many believe that the use of three dimensional input devices will alleviate this restriction and allow for a much more natural human-machine dialog. This thesis seeks to establish how factors dealing with visual feedback and task structure affect the ability to perform interactive tasks in a three dimensional virtual environment. The factors investigated were stereoscopic vision, motion parallax, stimulus arrangement and stimulus complexity. Four tasks were studied. These tasks were: point location, docking, line tracing and curve tracing. All the tasks used a six degree of freedom input device to control a pointer in a three dimensional virtual environment. Four experiments corresponding to the four tasks were conducted to investigate these factors. Among other things the results showed the following. Stereoscopic vision provided a strong benefit to positioning-based tasks, but this benefit was weakened in the case of tracing tasks. Motion parallax via head-tracking often had no effect upon task performance and where an effect was found it was often detrimental. The position of stimuli influenced performance across all of the tasks. The orientation of stimuli influenced performance in the task in which it was varied. / Science, Faculty of / Computer Science, Department of / Graduate

Cloud computing has provided many services to potential consumers, one of these services being the provision of network functions using virtualization. Network Function Virtualization is a new technology that aims to improve the way we consume network services. Legacy networking solutions are different because consumers must buy and install various hardware equipment. In NFV, networks are provided to users as a software as a service (SaaS). Implementing NFV comes with many benefits, including faster module development for network functions, more rapid deployment, enhancement of the network on cloud infrastructures, and lowering the overall cost of having a network system. All these benefits can be achieved in NFV by turning physical network functions into Virtual Network Functions (VNFs). However, since this technology is still a new network paradigm, integrating this virtual environment into a legacy environment or even moving all together into NFV reflects on the complexity of adopting the NFV system. Also, a network service could be composed of several components that are provided by different service providers; this also increases the complexity and heterogeneity of the system. We apply abstract architectural modeling to describe and analyze the NFV architecture. We use architectural patterns to build a flexible NFV architecture to build a Reference Architecture (RA) for NFV that describe the system and how it works. RAs are proven to be a powerful solution to abstract complex systems that lacks semantics. Having an RA for NFV helps us understand the system and how it functions. It also helps us to expose the possible vulnerabilities that may lead to threats toward the system. In the future, this RA could be enhanced into SRA by adding misuse and security patterns for it to cover potential threats and vulnerabilities in the system. Our audiences are system designers, system architects, and security professionals who are interested in building a secure NFV system. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection

Commodity hypervisors are widely deployed to support virtual machines on multiprocessor server hardware. Modern hypervisors are complex and often integrated with an operating system kernel, posing a significant security risk as writing large, multiprocessor systems software is error-prone. Attackers that successfully exploit hypervisor vulnerabilities may gain unfettered access to virtual machine data and compromise the confidentiality and integrity of virtual machine data. Theoretically, formal verification offers a solution to this problem, by proving that the hypervisor implementation contains no vulnerabilities and protects virtual machine data under all circumstances. However, it remains unknown how one might feasibly verify the entire codebase of a complex, multiprocessor commodity system. My thesis is that modest changes to a commodity system can reduce the required proof effort such that it becomes possible to verify the security properties of the entire system. This dissertation introduces microverification, a new approach for formally verifying the security properties of commodity systems. Microverification reduces the proof effort for a commodity system by retrofitting the system into a small core and a set of untrusted services, thus making it possible to reason about properties of the entire system by verifying the core alone. To verify the multiprocessor hypervisor core, we introduce security-preserving layers to modularize the proof without hiding information leakage so we can prove each layer of the implementation refines its specification, and the top layer specification is refined by all layers of the core implementation. To verify commodity hypervisor features that require dynamically changing information flow, we incorporate data oracles to mask intentional information flow. We can then prove noninterference at the top layer specification and guarantee the resulting security properties hold for the entire hypervisor implementation. Using microverification, we retrofitted the Linux KVM hypervisor with only modest modifications to its codebase. Using Coq, we proved that the hypervisor protects the confidentiality and integrity of VM data, including correctly managing tagged TLBs, shared multi-level page tables, and caches. Our work is the first machine-checked security proof for a commodity multiprocessor hypervisor. Experimental results with real application workloads demonstrate that verified KVM retains KVM’s functionality and performance.

published_or_final_version / Education / Master / Master of Science in Information Technology in Education

published_or_final_version / abstract / Computer Science and Information Systems / Master / Master of Philosophy

M. Tech. Business Information Systems / The banking sector allocates a great deal of their annual budget to Information Technology. To maintain and optimise activities such as software licensing, data security, business continuity and upgrading of computer hardware and general technology infrastructure to meet new organisational requirements, huge financial resources are deployed. One innovative approach to meeting these demands is using virtual desktop technology to extend the computer life, reduce IT costs, improve security and increase availability of technology. One may surmise from the experiences of these companies that if banks replace the current personal computers with virtual desktops they may realise the same benefits. With the introduction of Virtual Desktop Infrastructure (VDI) technology; the premise is that it will alleviate these issues currently faced by banks as all these functions can be done in one place instead of doing it on every individual PC. This study seeks to explore factors of VDI adoption and its impact in terms of reducing cost, hardware and software management, remote access, improved data security and recovery, better compliance and reduced energy consumption.

"Resource sharing between applications can significantly improve the resources required for all, which can reduce cost, and improve performance. Isolating resources on the other hand can also be beneficial as the failure or significant load on one application does not affect another. There is a delicate balance between resource sharing and resource isolation. Virtual machines may be a solution to this problem with the added benefit of being able to perform more dynamic load balancing, but this solution may be at a significant cost in performance. This thesis compares three different configurations for machines running application servers. It looks at speed at which a new application server can be started up, resource sharing and resource isolation between applications in an attempt to quantify the tradeoffs for each type of configuration."

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: p. 212-214. / by Robert Hunter Halstead, Jr. / Ph.D.