Thesis (M.Sc. (Computer Science)) - Rhodes University, 2007.

This thesis describes the design and development of both the hardware and software of an embedded, distributed control system using a LAN infrastructure for communication between nodes. The primary application of this system is for power monitoring and control at Rhodes University. Both the hardware and software have been developed to provide a modular and scalable system capable of growing and adapting to meet the changing demands placed on it. The software includes a custom written Internet Protocol stack for use in the embedded environment, with a small code footprint and low processing overheads. There is also Linux-based control software, which includes a web-based device management interface and graphical output. Problems specific to the application are discussed as well as their solutions, with particular attention to the constraints of an embedded system.

There is little literature available that is specific to the use of wireless local area network [WLAN) security among small, medium and micro enterprises (SMMEs) in South Africa. This research study developed a framework which may be used by SMMEs for the purposes of securing their WLANs. In view of the fact that the aim of the study was to develop a system for improving information technology security, the study followed a design science approach. A literature review was conducted on security control framework standards and WLAN technologies. The needs of SMMEs regarding WLANs were also established. The result of this process was an artefact in the form of a WLAN Security Control Framework for securing WLANs for SMMEs in South Africa. The suitability of the framework was validated by means of a focus group.

M.Com. (Computer Auditing) / With all the technology available in today’s world, people have become more connected to each other as well as to the world around them. This has been echoed by Rutledge (2009:1), who stated: “Emerging technologies are linking the world, but we no longer need wires and cables to connect people. People are no longer trapped by geography. We are, however, facing a digital tsunami as communications technology becomes cheaper, simpler, and more culturally-acceptable.” The new wireless technology has become an aid to most organizations, making networking simpler, cheaper and more effective, and has not only changed the way businesses operates but has changed the entire world of communications. It has not only caused a change in technology, but a change in the way of life. This is emphasized by Lawlor (2007:3), who stated: “Information technology has been a major driving force behind globalization and that information technology has now become a key component of a corporation’s global business strategy.” It is evident that the use of wireless technologies has changed the mode in which work is carried out and the manner in which communication takes place today. It has made it easier, more effective and efficient than before with wired technology. Wireless networks provide computing suppleness. It aids employees and individuals to take advantage of mobile networking for e-mail, Internet access, and sharing files regardless of where they are in the office or in a local area network (hereafter LAN). The advantage of the wireless setting is that it can be moved around at will, with no need for cables, leaving employees free to work from anywhere...

Master of Science

Bibliography: pages 77-80. / This is a study of the simulated performance of two local area networks, Ethernet and the MAP network, respectively based on the IEEE standards 802.3 and 802.4. The simulation language chosen is of the discrete event type rather than the more usual analytical model. This is done in order to observe the interaction between the various entities of a network in order to gain a better understanding of the method of operation of such a system. The performance demanded of a node entity by the networks is determined. The performance of some commercially available hardware is derived from manufacturer's specifications and compared with that required by the network. It is found that there is a significant disparity, with the network requirements far exceeding that of the hardware capabilities. The simulation models developed are used to determine the performance of the networks both with and without the limitations imposed by currently available hardware. While the inclusion of the hardware performance causes little ·loss in performance for the Ethernet network, it has a highly detrimental effect on that of the MAP network. A possible solution is found to this limitation which requires minimal change to the existing protocol. The conclusions reached are that with currently available hardware a group of nodes are able to fully utilise the performance of the Ethernet LAN although a single pair of nodes is unable to do so. With regard to the MAP network, the network performance is limited by that of the node performance although this can be offset to a certain extent by careful choice of one of the protocol parameters, or modification of the hardware design.

Master of Science

Master of Engineering

<p>This project is a token bus local area network simulator written in Pascal on an IBM PC compatible. The simulator is written for the Microsoft Windows operating environment and makes use of a graphical user interface for controlling the simulation. The program is object-oriented to make use of the Borland ObjectWindows Windows interface and because of the suitability of object-oriented programming to graphics and simulation applications. All basic token bus network functionalities specified by the Institute Of Electrical And Electronics Engineers (IEEE) 802.4 token bus standard are implemented in the simulation plus an added function to resolve duplicate node addresses. The network nodes and bus are drawn using Windows' color graphics. The state of each node is represented by text as well as the color and style each node is drawn in. The frame being transmitted is shown as large text within the bus object on the screen. The direction of data transfer on the bus is shown graphically as is the current location of the token among the nodes.</p> <p> The user of the simulation has the ability make any node active, inactive, or passive, or to make any node fail. The user may make a node send data to one other node or many other random nodes. The addresses of the nodes may also be changed. The user may pause, step through, or continue the simulation, control the simulation speed, control the error rate of data on the bus, and produce a lost token scenario.</p> / Master of Science

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