Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (M.S.)--University of Florida, 2001. / Title from title page of source document. Document formatted into pages; contains x, 188 p.; also contains graphics. Includes vita. Includes bibliographical references.

The aim of the study is to investigate what impact the use of VPN has on network performance. An empirical investigation using quantitative research methods was carried out. Two sample scenarios were involved in the study: scenario without VPN and scenario with VPN. In both scenarios, three applications were used in turns, an HTTP, an FTP, and a CBR. FTP was configured to use window size and packet size, while CBR used connection rate and packet size. On the other side, the number of connection was the only parameter used for HTTP. These applications were injected in a 100 Mbps fixed link of an NS2 simulation environment. Throughput and delay averages were measured respectively for the two scenarios and values compared using Student’s t-test. While the TCP and HTTP throughputs were found decreasing, the UDP throughput was not affected by the presence of this VPN. Concerning the delay; the TCP, UDP and HTTP delay were found increasing. / Electrical Engineering / M. Tech. (Electrical Engineering (Computer Systems))

D. Litt. et Phil. / Today, more and more organisations are adopting the use of the Internet and webbased technologies in the management of and provision of access to information and knowledge resources and services in digital formats. However, it appears that innovative use of the web is more pronounced in corporate organisations. For example, corporate organisations are using portals or sophisticated websites to conduct electronic commerce via the web and provide access to both internal and external information resources and services, accessed via the Internet, intranets, and extranets. The view of the researcher is that innovative use of the Internet and web-based technologies, such as portals, should not be the domain of the corporate world alone. The focus of this thesis is, therefore, to establish the potential application possibilities of portals in other types of organisations, especially agricultural research organisations in the Southern African Development Community (SADC) region. The main research problem addressed in this thesis was What is the nature and application possibility of agricultural information portals in the provision of webbased, value-added information services for researchers? To address the above research problem, literature relating to the historical development of the Internet and the World Wide Web, intranet and extranet applications in organisations, as well as portals and their applications, was reviewed. In addition, a study was made of international trends regarding the provision of access to digital agricultural information resources and services via the web, and a questionnaire survey was conducted to establish whether it was necessary to use portals to provide access to digital-based agricultural information resources and services in agricultural research organisations in the SADC region. ii Resulting from the literature reviews, the study of websites of international agricultural organisations, and the survey on the need for portals in agricultural research organisations in the SADC region, the study established that: · There are several potential applications of portals in agricultural research organisations. This led to the definition of the nature and major components of the type of portal that could serve the needs of researchers in agricultural research organisations. · There is a need for portals in agricultural research organisations in the SADC region. The current use of the web in these organisations in the region is largely limited to the development of brochureware types of websites, providing access to information contained in the organisations’ brochures. Therefore, there is need to upgrade from basic Web sites to advanced sites or portals, and the study concluded that in this regard there is a need for clear guidelines to assist agricultural research organisations to plan the deployment of their information portals. Currently, most organisations are using ad hoc approaches when developing their Web sites. The dissertation, furthermore, develops the definition of an agricultural information portal as a web-based application that is accessed via the intranet or extranet and provides a personalised and adaptive interface that enables agricultural researchers to discover, track, and interact with colleagues and other people, software applications, information resources, services and tools relevant to their research interests and work. Taking into account the major components and definition of an agricultural information portal, the study proposes guidelines for use in planning the deployment of portals in agricultural research organisations. The proposed guidelines are independent of specific portal design or development methodology, application domains, and techniques.

Thesis (M.Sc. (Hons.)) -- University of Western Sydney, 2005. / A thesis submitted in fulfillment of the requirements for the award of the degree Master of Science (Honours) to the University of Western Sydney on March 2005. Includes bibliography.

M.Sc. (Information Technology) / The internet grew exponentially over the last decade. With more information available on the web, search engines, with the help of web crawlers also known as web bots, gather information on the web and indexes billions of web pages. This indexed information helps users to find relevant information on the internet. An extranet is a sub-set of the internet. This part of the web controls access for a selected audience to a specific resource and are also referred to as restricted web sites. Various industries use extranets for different purposes and store different types of information on it. Some of this information could be of a confidential nature and therefore it is important that this information is adequately secured and should not be accessible by web bots. In some cases web bots can accidently stumble onto poorly secured pages in an extranet and add the restricted web pages to their indexed search results. Search engines like Google, that are designed to filter through a large amount of data, can accidently crawl onto access restricted web pages if such pages are not secured properly. Researchers found that it is possible for web crawlers of well known search engines to access poorly secured web pages in access restricted web sites. The risk is that not all web bots have good intentions and that some have a more malicious intent. These malicious web bots search for vulnerabilities in extranets and use the vulnerabilities to access confidential information. The main objective of this dissertation is to develop a prototype web bot called Ferret that would crawl through a web site developed by a web developer(s). Ferret will try to discover and access restricted web pages that are poorly secured in the extranet and report the weaknesses. From the information and findings of this research a best practice guideline will be drafted that will help developers to ensure access restricted web pages are secured and invisible to web bots.

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.

Cheung Yu Hoi Ocean. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 65-70). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Aims --- p.2 / Chapter 1.3 --- Contributions --- p.3 / Chapter 1.4 --- Thesis Outline --- p.3 / Chapter 2 --- Virtual Private Network and FreeS/WAN --- p.4 / Chapter 2.1 --- Introduction --- p.4 / Chapter 2.2 --- Internet Protocol Security (IPSec) --- p.4 / Chapter 2.3 --- Secure Virtual Private Network --- p.6 / Chapter 2.4 --- LibDES --- p.9 / Chapter 2.5 --- FreeS/WAN --- p.9 / Chapter 2.6 --- Commercial VPN solutions --- p.9 / Chapter 2.7 --- Summary --- p.11 / Chapter 3 --- Cryptography and Field-Programmable Gate Arrays (FPGAs) --- p.12 / Chapter 3.1 --- Introduction --- p.12 / Chapter 3.2 --- The Data Encryption Standard Algorithm (DES) --- p.12 / Chapter 3.2.1 --- The Triple-DES Algorithm (3DES) --- p.14 / Chapter 3.2.2 --- Previous work on DES and Triple-DES --- p.16 / Chapter 3.3 --- The IDEA Algorithm --- p.17 / Chapter 3.3.1 --- Multiplication Modulo 2n + 1 --- p.20 / Chapter 3.3.2 --- Previous work on IDEA --- p.21 / Chapter 3.4 --- Block Cipher Modes of operation --- p.23 / Chapter 3.4.1 --- Electronic Code Book (ECB) mode --- p.23 / Chapter 3.4.2 --- Cipher-block Chaining (CBC) mode --- p.25 / Chapter 3.5 --- Field-Programmable Gate Arrays --- p.27 / Chapter 3.5.1 --- Xilinx Virtex-E´ёØ FPGA --- p.27 / Chapter 3.6 --- Pilchard --- p.30 / Chapter 3.6.1 --- Memory Cache Control Mode --- p.31 / Chapter 3.7 --- Electronic Design Automation Tools --- p.32 / Chapter 3.8 --- Summary --- p.33 / Chapter 4 --- Implementation / Chapter 4.1 --- Introduction --- p.36 / Chapter 4.1.1 --- Hardware Platform --- p.36 / Chapter 4.1.2 --- Reconfigurable Hardware Computing Environment --- p.36 / Chapter 4.1.3 --- Pilchard Software --- p.38 / Chapter 4.2 --- DES in ECB mode --- p.39 / Chapter 4.2.1 --- Hardware --- p.39 / Chapter 4.2.2 --- Software Interface --- p.40 / Chapter 4.3 --- DES in CBC mode --- p.42 / Chapter 4.3.1 --- Hardware --- p.42 / Chapter 4.3.2 --- Software Interface --- p.42 / Chapter 4.4 --- Triple-DES in CBC mode --- p.45 / Chapter 4.4.1 --- Hardware --- p.45 / Chapter 4.4.2 --- Software Interface --- p.45 / Chapter 4.5 --- IDEA in ECB mode --- p.48 / Chapter 4.5.1 --- Multiplication Modulo 216 + 1 --- p.48 / Chapter 4.5.2 --- Hardware --- p.48 / Chapter 4.5.3 --- Software Interface --- p.50 / Chapter 4.6 --- Triple-DES accelerator in LibDES --- p.51 / Chapter 4.7 --- Triple-DES accelerator in FreeS/WAN --- p.52 / Chapter 4.8 --- IDEA accelerator in FreeS/WAN --- p.53 / Chapter 4.9 --- Summary --- p.54 / Chapter 5 --- Results --- p.55 / Chapter 5.1 --- Introduction --- p.55 / Chapter 5.2 --- Benchmarking environment --- p.55 / Chapter 5.3 --- Performance of Triple-DES and IDEA accelerator --- p.56 / Chapter 5.3.1 --- Performance of Triple-DES core --- p.55 / Chapter 5.3.2 --- Performance of IDEA core --- p.58 / Chapter 5.4 --- Benchmark of FreeSAVAN --- p.59 / Chapter 5.4.1 --- Triple-DES --- p.59 / Chapter 5.4.2 --- IDEA --- p.60 / Chapter 5.5 --- Summary --- p.61 / Chapter 6 --- Conclusion --- p.62 / Chapter 6.1 --- Future development --- p.63 / Bibliography --- p.65

Information Technology is advancing at a frightening pace. Cloud computing and its subset, Software as a Service (SaaS), are rapidly challenging traditional thinking for enterprise-level application and infrastructure provision. The project-centric nature of the construction industry provides an environment where the utilisation of SaaS is commercially appropriate, given its ability to provide rapid set-up and predictable costs at the outset. Using project extranets, the construction industry has been - unusually for it as an industry sector - early-adopters of this cloud computing model. However, findings from the research highlight that there is a gap in the information and documents that pass from the construction phase into the operational phase of a building. This research considers examples of the SaaS IT model and how it has been used within a construction and facilities management industry context. A prototype system was developed to address the requirements of facilities management work order logging and tracking process. These requirements were gathered during detailed case studies of organisations within both the construction and facilities management sectors with a view to continue the use of building-specific information through its full life-cycle. The thesis includes a summary of the lessons learnt through system implementation within the construction-contracting organisation Taylor Woodrow, and it concludes with an IT strategy proposal that was developed based on a cloud computing model.

Se presenta a los túneles de datos como propuesta de solución para la interconexión de sedes de una misma organización, separadas geográficamente, a través de enlaces de comunicaciones entre redes privadas soportadas en redes públicas como internet. Para la implementación de escenarios de redes de computadoras, se establecen ambientes controlados y virtualizados que se analizan a través de la captura de paquetes con un analizador de protocolos y/o con mensajes propios de aplicaciones para detección de errores o diagnóstico, con el fin de validar que los protocolos se comportan de acuerdo a como están definidos en los estándares y proponer recomendaciones para su uso práctico. En la Introducción se procede a definir el objetivo general y el alcance propuesto para el desarrollo del presente trabajo, teniendo como soporte para la implementación de servicios y aplicaciones al software libre. En el Capítulo 1 se describen y presentan conceptos básicos sobre redes de computadoras, el modelo que permite compartir recursos y servicios, así como el modelo que describe y permite clasificar los diferentes protocolos de red. Se describe el protocolo de internet (IP) y como se complementa con el protocolo de mensajes de control de internet (ICMP) como herramienta de diagnóstico o detección de fallas. Así también, se define túnel de datos y se mencionan los túneles en el alcance del presente trabajo. En el Capítulo 2 se describen herramientas para la creación y ejecución de entornos virtuales basados en User Mode Linux (UML). La ejecución de entornos virtuales se da a través de la aplicación Simtools, que ofrece varios escenarios preconfigurados utilizando Virtual Network User Mode Linux (VNUML). Se explica cómo instalar simtools y cómo funcionan sus principales comandos y archivos de configuración. Por otro lado, con varias funcionalidades añadidas al kernel de Linux, es posible proveer entornos virtuales con sus propios espacios de procesos y redes, completamente aislados, llamados contenedores. Se presenta un enfoque para construir contenedores Linux: LXC (Linux Containers). En el Capítulo 3 se implementan las topologías de red enlos entornos virtualizados y sobre estas se implementan los túneles: túnel IP en modo IP y modo GRE, túnel SSH en un entorno VNUML. Además, se implementa en la capa de enlace el túnel llamado GRETAP, en un entorno LXC. Finalmente, se presentan conclusiones y recomendaciones basadas en los resultados obtenidos en las prácticas en escenarios virtuales, capturas de paquetes y mensajes de respuesta y/o diagnóstico obtenidos. / Tesis