Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Elektronik Bilgisayar Eğitimi Anabilim Dalı, 2006. / Kaynakça var.

Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed March 27, 2008) Includes bibliographical references (p. 55-56).

Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 21, 2008) Includes bibliographical references (p. 48).

Thesis (Ph.D.) - Carleton University, 2007. / Includes bibliographical references (p. 210-215). Also available in electronic format on the Internet.

Thesis (MScEng)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: The aim of this thesis is to investigate a design of a microcontroller based embedded system that will be used to minimise cable harness on the SUNSAT micro-satellite. The system is called CAN node. The CAN node(s) implements CAN (Controller Area Network) serial bus architecture protocol. The protocol is implemented on the two nodes to transport data from the TCMD tot he 0 ther trays 0 f SUNSAT. CAN node( s) design proj ect focuses on the TCMD tray, because it is the central point for data communication in SUNSAT and it acts as the eyes and hands of the satellite's operator. As a result most of the communication cables are located at this tray. The two nodes are called TX-node and RX-nodes. The TX-node is used to collect data from the TCMD tray and transmits them serially to RX-node. The RX-nodes receives the TCMD data from TX-node and transmits these data to their respective nodes. In application RX-nodes need to be ten, but only one is used for testing purpose. The design had its shortcomings, of which they are discussed in this thesis. The recommendations of an ideal system are also given to elaborate how the system should behave in the real situation. Despite its shortcomings, the CAN node(s) project has successfully proven that cable harness on the TCMD tray of SUNSAT can be minimised by using CAN technology. / AFRIKAANSE OPSOMMING: Die doel van hierdie tesis is om die ontwerp van 'n mikro-beheerder gebaseerde stelsel wat die SUNSA T mikro-satelliet kabel harnas sal verklein, te ondersoek. Die stelsel word die CAN nodus genoem. Die CAN nodus implementeer die CAN (Controller Area Network) bus argitektuur protokol. Die protokol is op twee nodusse geïmplementeer om data vanaf die TCMD na ander laaie van SUNSAT te voer. Die CAN nodus ontwerp fokus op die TCMD laai, want dit is die sentrale punt vir data kommunikasie in SUNSA T en dit tree soos die oog en hande van die satelliet operateur op. As 'n gevolg, is die meeste van die kommunikasie kabels in hierdie laai. Die twee nodusse is genoem TXnodus en RX-nodus. TX-nodus word gebruik om die data van die TCMD af te kollekteer en dan versprei hulle tot hulle onderskeie nodusse. In die toepaslik moet daar tien RX-nodusse wees, maar net een is gebruik terwille van die toets. Die ontwerp het sy eie tekortkomings, wat in hierdie tesis bespreek word. Die rekommendasie van 'n ideale stelsel is ook gemaak om te bewys hoe die stelsel dit in 'n ware situasie moet gedra. Ongeag die tekortkomings daarvan, het die CAN-nodus projek suksesvol bewys dat die kabel harnas in die TCMD laai van SUNSAT kan verminder word deur die gebruik van die CAN tegnologie.

Thesis (MEng)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: The Attitude Determination and Control System (ADCS) of the Stellenbosch University Satellite (SUNSAT I) is an integrated system providing some redundancy and the necessary data management to control the spacecraft. However, the redundancy is not easily accessible and there is a lack in flexibility when testing individual modules during integration or when the system needs to be extended. The objective of this thesis was thus to develop a high reliability, flexible, modular communication system that included some type of redundancy to manage real-time data and to prevent severe malfunctioning of the entire system. The first step in the project's development methodology was to summarise the requirements and specifications by studying the current ADCS architecture and data management. An investigation into the Controller Area Network (CAN) protocol showed that this technology would fit the requirements very well, leading to the design and implementation of several concept topologies based on CAN. Thereafter, a demonstration model consisting of three prototype nodes was composed. The performance of the so called dual CAN node was analysed and an extrapolation was 'made to determine whether the architecture could support the complete ADCS. It was demonstrated that the dual CAN node provides enough room to accommodate all the processors, actuators and sensors of the ADCS. At the same time, it was shown that reliability and robustness was increased by enhanced redundancy at a node-level as well as at the greater system-level. A dual CAN bus was provided for redundancy at a node-level. At the system-level, the command and data-gathering modules (ACP or OBC's) can now effectively be multiplexed on the network of actuators and sensors. Furthermore, it was shown that error detection capabilities and diagnostics can be enhanced and the complexity of the communication architecture and related wiring harnesses can be reduced. This allows easier access to modules and simplifies development. / AFRIKAANSE OPSOMMING: Die Attitude Determination and Control System (ADCS) van Stellenbosch University Satellite (SUNSAT I) is 'n geïntegreerde stelsel wat voorsiening maak vir 'n mate van oortolligheid en 'n vermoeë om stelseldata te bestuur vir goeie satellietbeheer. Nietemin, hierdie oortolligheid is nie baie toeganklik nie en daar is 'n gebrek aan aanpasbaarheid tydens die toets en integrasie van individuele modules of moontlike stelseluitbreidings. Die doelwit van hierdie tesis was dus die ontwikkeling van 'n betroubare, aanpasbare, modulêre kommunikasie stelsel wat 'n tipe oortolligheid insluit sodat intydse data bestuur kan word en algehele stelselondergang vermy kan word. Die eerste stap in die projek se ontwikkelings metodiek was om 'n opsomming te verkry van die vereistes en spesifikasies deur die huidige ADCS se argitektuur en databestuur te ondersoek. 'n Ondersoek na die Controller Area Network (CAN) protokol het getoon dat hierdie tegnologie aan baie van die vereistes voldoen. Dit het aanleiding gegee tot die ontwerp en implementering van 'n paar konsep ontwerpe gebaseer op CAN. Daarna is 'n demonstrasie model bestaande uit drie prototipe nodusse gebou. Die werksverrigting van die sogenoemde dual CAN node, is ondersoek en 'n ekstrapolasie was gemaak om vas te stelof die argitektuur die volkome ADCS kan huisves. Deur demonstrasie was daar getoon dat die dual CAN node wel genoeg ruimte verskaf om al die verwerkers, aktueerders en sensors van die ADCS te akkommodeer. Daar was terselfdertyd getoon dat betroubaarheid en robuustheid verhoog is deur die verbeterde oortolligheid op 'n node-vlak sowel as op die groter stelsel-vlak. 'n Dubbele CAN bus is gebruik vir oortolligheid op 'n node-vlak. Op 'n stelsel-vlak kan die bevel-en-dataversamelings modules (ACP en aBC's) effektief gemultipleks word op die netwerk van aktueerders en sensors. Daar was verder getoon dat die foutopspoorings vermoeë en diagnostiese vermoeë verbeter kan word en die kompleksiteit van die kommunikasie argitektuur en ooreenkomstige kabelharnasse vereenvoudig kan word. Die gevolg is vereenvoudigde toegang tot modules en vergemaklikde opgradering.

Even if all the technical security solutions appropriate for an organisation’s network are implemented, for example, firewalls, antivirus programs and encryption, if the human factor is neglected then these technical security solutions will serve no purpose. The greatest challenge to network security is probably not the technological solutions that organisations invest in, but the human factor (non-technical solutions), which most organisations neglect. The human factor is often ignored even though humans are the most important resources of organisations and perform all the physical tasks, configure and manage equipment, enter data, manage people and operate the systems and networks. The same people that manage and operate networks and systems have vulnerabilities. They are not perfect and there will always be an element of mistake-making or error. In other words, humans make mistakes that could result in security vulnerabilities, and the exploitation of these vulnerabilities could in turn result in network security breaches. Human vulnerabilities are driven by many factors including insufficient security education, training and awareness, a lack of security policies and procedures in the organisation, a limited attention span and negligence. Network security may thus be compromised by this human vulnerability. In the context of this dissertation, both physical and technological controls should be implemented to ensure the security of the SANReN network. However, if the human factors are not adequately addressed, the network would become vulnerable to risks posed by the human factor which could threaten the security of the network. Accordingly, the primary research objective of this study is to formulate guidelines that address the information security related human factors in the rolling out and continued management of the SANReN network. An analysis of existing policies and procedures governing the SANReN network was conducted and it was determined that there are currently no guidelines addressing the human factor in the SANReN beneficiary institutions. Therefore, the aim of this study is to provide the guidelines for addressing the human factor threats in the SANReN beneficiary institutions.

A gerência de redes de computadores cresce a, medida que são necessárias redes mais seguras, menos vulneráveis a falhas e para reduzir a sobrecarga de trabalho dos administradores de rede. Gerenciar elementos físicos das redes de computadores tem sido a tônica da gerencia de redes. Porem, gerenciar as aplicações também a muito importante, pois são o ponto de interação do usuário com a rede. Há grupos trabalhando na padronização da gerencia das aplicações, através da definição de Management Information Bases (MIBs) específicas para as aplicações. Recentemente foi publicada a MIB específica para correio eletrônico Internet [KIL 94]. Alem de grupos oficiais, como o IFIP Working Group 6.6, outras pessoas, também a nível de Brasil, tem desenvolvido trabalhos na áreas de gerencia de aplicações [CAR 94]. Este trabalho propõe um paradigma para gerencia de uma das entidades funcionais do Message Handling System (MHS) X.400, o Agente de Transferência de Mensagens (ATM). O MHS X.400 e a aplicação de correio eletrônico para o ambiente OSI. O correio eletrônico a uma das aplicações mais populares na comunidade de redes de computadores e atualmente tem sido cogitado como base para muitas outras aplicações. A definição conceitual do paradigma de gerencia baseou-se na estrutura de gerencia do modelo OSI, mas a implementação efetiva do protótipo utiliza o protocolo de gerencia da arquitetura Internet, o SNMP. As fases de definição e levantamento dos requisitos para gerencia de um Agente de Transferência de Mansagens (ATM) basearam-se nos modelos organizacional, funcional e informacional definidos pela ISO. 0 modelo organizacional define a hierarquia entre as entidades de gerencia, ou seja, a hierarquia entre agentes e gerentes. O modelo funcional descreve os requisitos para gerencia do ATM segundo as áreas funcionais do modelo: gerencia de fa1has, gerencia de configuração, gerencia de contabilidade, gerencia de desempenho e gerencia de segurança. 0 modelo informacional define a MIB, ou seja, os objetos que serão monitorados. A validação do modelo conceitual foi realizada através da implementação do protótipo. No protótipo foram utilizados os ambientes ISO Development Environment (ISODE), PP e SunNet Manager (SNM). A implementação do protótipo, alem de validar os conceitos te6ricos, foi útil para a obtenção de experiência com relação a integração entre os diversos ambientes. / The network management has been grown due to the need of more secure networks and to reduce the network adminstrator work. The network physical elements management has been the most important topic in network management, but application management is also important because it is the interaction point between users and networks. There are groups working on standardization of application management defining Managemet Information Bases (MIBs) specifics for application management. A Management Information Base for Internet eletronic mail [KIL 941 was recently published. Beyond official groups, such as IFIP Working Group 6.6, there are other people investigating the management process of several well-known applications [CAR 94]. This work proposes a paradigm for the management of one funcional entity of Message Handlig System (MHS) X.400, the Message Transfer Agent (MTA). The MHS X.400 is the eletronic mail application for OSI environment. The eletronic mail is one of most popular network application and it has been indicated to be the base for other applications. The conceptual definition of management paradigm was based in OSI management framework, but the actual prototype implementation uses the SNMP protocol from Internet framework. The definition and elicitation of management requirements for MTA management were based on organization, function and information models defined by ISO. The organization model defines the hierarchy between the management entities, i.e., the hierarchy between agents and managers. The organization model describes the MTA management requirements by the functional areas: fault management, configuration managemet, accounting management, performance management and security managent. The information model defines the MIB, i.e., the managed objects. The conceptual model validation was realized throught prototype implementation. For this validation some softwares were used such as ISO Environment Development (ISODE) and PP that are sharewares commonly used in academic environments and SunNet Manager (SNM) that is a comercial software. This implementation prototype was helpful to apply the network management concepts and to get knowhow about real network managemnt softwares utilization and integration.

A research report submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Arts in the field of ICT Policy and Regulation / The research report examined the value brought by NRENs, by investigating the utilization of the South African National Research Network (SANReN) at the University of the Witwatersrand (Wits). It explored the SANReN as the main international bandwidth service for the university and assessed how the university is able to efficiently provide a range of e-services in scientific research through the NREN. Wits scientists engaged in data intensive research and international research collaboration shared the view that the SANReN infrastructure is critical to such work, however due to infrastructure limitations at university level, it is sometimes difficult to maximize the value of this dedicated network, where data storage capacity is low. A wide range of e-services, such as grid computing, use SANReN, but are limited by international bandwidth. A further problem is the high cost of international bandwidth, particularly as the demand for bandwidth increases with the amount of data required in scientific research. The biggest challenge is the growth of demand and the ability to meet this demand. As scientific research relies on real time data, but experiences problems with data storage, advanced data infrastructure is needed in the form of a medium sized data centre, which would be used for storing and transferring large data sets and terabytes of data in and out of the country. In conclusion, although SANReN makes it possible for big science projects to take place at universities, it is somewhat difficult to measure the value that SANReN brings, due to the many limitations mentioned. Therefore a matrix to measure outputs and value of SANReN is required, as proposed in Chapter 6 of this research report. / GR2017

Thesis (Ph.D.) - Carleton University, 2006. / Includes bibliographical references (p. 139-144). Also available in electronic format on the Internet.