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    Teacher professional learning for technology integration in mathematics classrooms through online learning communities : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Information Technology at Massey University, Albany, New Zealand
    (Massey University, 2018) Abidin, Zaenal
    The new school curricula in Indonesia emphasise the integration of technology into instructional practices. The infusion of technology in mathematics education requires teachers to align their teaching practices with ongoing technological innovations. Integrating technology into mathematics classrooms requires teachers to have a good knowledge of mathematics content, technology and pedagogy. Teachers also need to consider their school environments. Existing teacher professional development programmes are seen to be failing to meet teacher needs regarding content delivery that sometimes does not match the existing school conditions. The premise underlying this research is that the use of an online learning community (OLC) may present a possible solution to the current challenges. Thus, the intention of this study was to investigate the potential of OLCs to help develop teachers’ learning to fulfil their professional needs in integrating technology with the teaching of mathematics. An ethnographic approach was used to investigate the phenomenon of teacher learning within an OLC and the implementation of the new knowledge acquired in their mathematics teaching practices. Empirical data from five case studies were used to examine how participation in the OLC affected teaching practices for five teachers. The results revealed that teacher participation in an OLC offered opportunities and challenges. Teachers de-privatized their practices as they actively engaged in social learning interactions to share knowledge and help each other with the appropriate use of technology in teaching mathematics. Teachers also faced some challenges, which impeded them. These challenges included differences in school policies, such as restrictions on using social media and limited technical infrastructure, which hindered teachers from fully leveraging the OLC. Teachers with less experience in teaching with technology and with low levels of technology skills tended to be passive in the OLC. Cultural contexts revealed that lack of experience and caution about expressing opinions made teachers feel ewuh pakewuh, a shyness in openly expressing their thoughts. Despite these barriers, the study provided evidence that teachers improvised and dealt with situations as they rose. The findings of this study provided evidence that participation in the OLC had significant impacts on teachers’ professional learning. Teachers altered their mode of using technology either as a partner or as an extension of self as they gained more confidence in their own learning. The teachers gradually transformed their participation from peripheral to full participation in promoting the use of technology for teaching mathematics. The research provides new insights into ways teachers can be helped to develop their professional learning in the use of technology for teaching mathematics through participation in OLCs. Particularly for Indonesia, the findings of this research provide an OLC-based model that could be implemented in other contexts that share similar technology landscapes and sociocultural heritages.
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    Effective security analysis for combinations of MTD techniques on cloud computing : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Ph.D.) in Computer Science, Massey University
    (Massey University, 2019) Alavizadeh, Hooman
    Moving Target Defense (MTD) is an emerging security mechanism that can introduce a dynamic defensive layer for a given system by changing the attack surface. MTD techniques are useful to address security issues in cloud computing. MTD techniques are classified into three main categories: Shuffle, Diversity, and Redundancy. Shuffle MTD techniques can rearrange the system's components (e.g., IP mutation). They confuse the attackers by hardening the reconnaissance process and wasting the information collected by the attackers. Diversity MTD techniques change the variants of a system's component (e.g., operating systems), which makes an attack more difficult and costly because the attackers encounter a new set of vulnerabilities. Redundancy MTD techniques increase the system components' replicas. They can be used to increase system dependability (e.g., reliability or availability) by providing redundant ways of providing the same services when some system components are compromised. Since deploying each MTD technique may affect the others and also have different effects on the system (e.g., one can enhance the security and another can provide service's availability), it is important to combine MTD techniques in such a way that they can support each other directly or indirectly. This research first conducts an extensive survey of MTD literature to realize and summarize the key limitations of the current MTD studies. We reveal that (i) there is a lack of investigation on the combination of MTD techniques, (ii) relatively less effort has been made to evaluate the effectiveness of MTD techniques using security analysis, and (iii) there is a shortcoming in the validation of MTD techniques on more realistic cloud testbeds. We focus on the theoretical aspects of combining MTD techniques and provide formalization to combine MTD techniques in order to address those limitations. First, we achieve this by combining Shuffle and Redundancy to find a trade-off between System Risk and Reliability. Then, we provide a formal mathematical definition to combine Shuffle and Diversity to increase security while narrowing the scope for potential attacks. We evaluate the effectiveness of the proposed combined techniques using Graphical Security Models (GSMs) and incorporating various security metrics. We extend the combination of MTD techniques by including Redundancy besides Shuffle and Diversity. We perform an in-depth analysis on combining those MTD techniques to find out a trade-off between security alongside the reliability of the cloud. We show that if those MTD techniques are combined properly, it not only improves the cloud's security posture but also it increases the reliability of the cloud. Moreover, we study the economic metrics to show how MTD techniques can be deployed in a cost effective way. We also propose an Optimal Diversity Assignment Problem (O-DAP) to find the optimal solution for deploying Diversity over cloud. Finally, we design and develop an automated cloud security framework to evaluate the cloud security posture and adapt MTD techniques on the real cloud platform. We demonstrate the feasibility, adaptability, and usability of implementing MTD techniques on UniteCloud which is a real private cloud platform.
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    An implementation of X.25 over TCP/IP : a thesis presented in partial fulfilment of the requirements for the degree of Master of Technology in Computing Technology at Massey University
    (Massey University, 1991) Rasiah, Ajitkumar JW
    Computer Networks are being used increasingly around the world. More importantly, many of these networks are interconnected by gateways, allowing a user in one geographical location to send and receive messages from a host located elsewhere. The International Standards Organisation (ISO) has proposed the Open Systems Interconnection (OSI) Reference Model as a basis for building computer networks and the protocols which are used on those networks. Developers of networks are encouraged to follow these guidelines so that their networks may have an 'open architecture'. This thesis examines two networking protocols, CCITT's X.25 Recommendation and TCP/IP. It continuously refers back to the OSI Reference Model as it describes the design of these protocols. It then looks at an implementation of X.25 over TCP/IP, which will allow users on non-X.25 hosts to develop and run X.25 applications courtesy of a separate host that supports X.25.
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    Wide area techniques in a local area network : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Computer Science at Massey University
    (Massey University, 1986) Murphy, Michael
    Packet switching networks have been developed on a large scale (national or even international) as a means for enabling inter-computer communication. They spread the responsibility for data handling amongst a number of "nodes". In contrast, local area networks are restricted to a single site or organisation, and depend on the reliable operation of a central facility ( sometimes a computer, sometimes a shared communication cable). This thesis describes the design and successful implementation of MASSEYNET, a local area network embodying wide area techniques. The aim of the network is to provide a cheap system which will permit communication between devices located throughout Massey University, and permit individual terminals to interface to any one of the attached devices.
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    A Java implementation of a Linda-like Tuplespace system with nested transactions : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Computer Science at Massey University, Albany, New Zealand
    (Massey University, 2006) Yao, Yinan
    The Tuplespace model is considered a powerful option for the design and implementation of loosely coupled distributed systems. In this report, the features of the Tuplespace model are examined as well as the issues involved in implementing such a Tuplespace system based on Java. The system presented includes the function of Transactions: a collection of operations that either all succeed or all fail. The system also permits Nested Transactions: an extension of transactions. Nested transactions have a multi-level grouping structure: each nested transaction consists of zero or more operations and possibly some nested transactions. The key advantages offered by nested transactions include that they enable the failure of an operation to be isolated within a certain scope without necessarily aborting the entire transaction, and they allow programmers to sub-divide a complex operation into a number of smaller and simpler concurrent operations. The other features of nested transactions are also examined in this report. Finally, the testing results indicate that it is possible to build an efficient, scalable, and transaction secured distributed application that relies on the Tuplespace model and the system developed for this research.
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    Bio-mirrors and networking security : for the partial fulfilment of Masters of Information Sciences, Information Systems major, 2006
    (Massey University, 2006) Mubayiwa, Douglas
    Bioinformatics databanks have been the source of data to bioscience researchers over the years. They need this information especially in the analysis of raw data. When this data is needed, it has to be readily available. This thesis seeks to address the current problems of unavailable data at a critical time. Continued retrieval of data from far away sites is expensive in both time and network resources. Care must also be taken to secure this data otherwise by the time it reaches the researcher, it will be useless. In response to this problem being addressed, this thesis describes a way to move data securely so that the necessary data is stored nearest to whoever requires it. A proposed initial prototype has been implemented with capacity to grow. The overall architecture of the system, the prototype and other related issues are also discussed in this thesis.
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    The design of a network command language : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Computer Science at Massey University
    (Massey University, 1980) Jenkins, Phillip Campbell
    Most computer series have their own distinct operating system control language. At present there is no world-wide standard control language, but the recent development of heterogeneous networks, where users may access many different computers, has highlighted the need for one. A project to set up an experimental network, called KIWINET, between Massey and Victoria Universities, initiated research into the design of a standard control language for the network. The result of this research is a high-level, block structured language called the Network Command Language (NCL). The design of this language and its implementation are discussed.
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    Maximising the effectiveness of threat responses using data mining : a piracy case study : this thesis presented in partial fulfillment of the requirements for the degree of Master of Information Sciences in Information Technology, School of Engineering and Advanced Technology at Massey University, Albany, Auckland, New Zealand
    (Massey University, 2015) Lee, Seung Jun
    Companies with limited budgets must decide how best to defend against threats. This thesis presents and develops a robust approach to grouping together threats which present the highest (and lowest) risk, using film piracy as a case study. Techniques like cluster analysis can be used effectively to group together sites based on a wide range of attributes, such as income earned per day and estimated worth. The attributes of high earning and low earning websites could also give some useful insight into policy options which might be effective in reducing earnings by pirate websites. For instance, are all low value sites based in a country with effective internet controls? One of the practical data mining techniques such as a decision tree or classification tree could help rightsholders to interpret these attributes. The purpose of analysing the data in this thesis was to answer three main research questions in this thesis. It was found that, as predicted, there were two natural clusters of the most complained about sites (high income and low income). This means that rightsholders should focus their efforts and resources on only high income sites, and ignore the others. It was also found that the main significant factors or key critical variables for separating high-income vs low-income rogue websites included daily page-views, number of internal and external links, social media shares (i.e. social network engagement) and element of the page structure, including HTML page and JavaScript sizes. Further research should investigate why these factors were important in driving website revenue higher. For instance, why is high revenue associated with smaller HTML pages and less JavaScript? Is it because the pages are simply faster to load? A similar pattern is observed with the number of links. These results could form a study looking into what attributes make e-commerce successful more broadly. It is important to note that this was a preliminary study only looking at the Top 20 rogue websites basically suggested by Google Transparency Report (2015). Whilst these account for the majority of complaints, a different picture may emerge if we analysed more sites, and/or selected them based on different sets of criteria, such the time period, geographic location, content category (software versus movies, for example), and so on. Future research should also extend the clustering technique to other security domains.
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    Analysis and modelling quality of experience for web based services : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Network Engineering at Massey University, Palmerston North, New Zealand
    (Massey University, 2013) Nguyen, Le Thu
    Web technologies are advancing at a rapid pace and they provide users with better quality and advanced features for their web browsing experience. The research reported in this thesis is focused on the “Analysis and Modelling Quality of Experience for Web based services”. We present a reliable model for measuring and analysing QoE in Web Surfing scenarios based on network traces. We demonstrate that, by integration of further human perception factors involving content and state of mind (SOM) into the assessment, the overall model performance has been improved. The models enable users to feedback their opinion of their Web interactions by revealing the way in which they are interacting with the system rather than by explicitly providing their opinion via a subjective approach such as through a questionnaire. A comprehensive set of metrics was developed to evaluate the overall customer QoE. The results certainly help to get a better understanding on how web surfing is experienced by users. We have identified existing shortcomings in our knowledge for establishment of QoE and we have proceeded to discuss the current state-of-the-art in QoE modelling for Web based services. We have utilized orthogonal arrays using the Taguchi approach to construct our experiments in order to characterize the application, as well as establishing network performance metrics in our QoE assessment model to ease the experimental load and to reduce time and cost of conducting such experiments. We propose a further experiment with our proposed session control to reduce the boredom effects from users which may impact on their subjective assessments. We propose two further metrics that are related to content and SOM into our QoE assessment. The objective metric of content has been investigated and evaluated showing its effects on QoE. The subjective metric based on SOM has been captured subjectively by users’ feedback showing random change via customer browsing. We have also investigated the applicability of a mixed effects model in predicting QoE in World Wide Web based multi-media services. An analysis is presented of both objective factors and a human factor that may impact on the outcomes of observations. The third model is developed to account for these factors and other potential covariates to QoE assessment during the course of our experiments.
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    The impact of internet on business : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University
    (Massey University, 2002) Wallace, Catherine May
    The purpose of this thesis is to critically examine the impact of Internet on business with a particular emphasis on the New Zealand business situation. The focus is on the human elements rather than the technical aspects affecting organisations. The literature review establishes the context for the study with an overview of the development and progress of the Internet as a key component of the business environment. The information gathered from early stages of the research provided a cross-sectional analysis of Internet use in New Zealand industry sectors. Information gained served as a basis for selecting businesses for a more in-depth analysis for face-to-face interviews. A range of interviews were held with participants from organisations that were in the high, moderate and low Internet adoption sectors as identified by the questionnaire responses. Questionnaires were sent to businesses representing the full range of industry sectors via traditional paper channels. An industry- wide, New Zealand- wide sample was sought to give baseline data on New Zealand organisations to gain an understanding of current and future uses. To assess the issues involved in the future application of modern computer communications, issues such as cost-benefit analysis, privacy, security, access to information services and databases, competitive advantage, information management, public relations, marketing and electronic commerce will be explored. A range of issues identified from both the online and offline literature that seemed indicative of emerging and future trends formed the basis of the questions. Once the paper questionnaires had been returned, a comparable sample of respondents was sought, again indicative of all seventeen industry sectors. All respondents in this sample were from organisations that at least had email, even if they did not yet have a presence on the Internet. These customers of Internet Service Providers were sent a largely identical questionnaire by email. The aim was to gather data about organisations already online to identify any early-adopter characteristics and to gather more specific detailed information applicable to this group as existing Internet users. The final research phase was a longitudinal study using a case study methodology. Selected organisations were followed through a three-part process of planning for technology, acquisition and implementation of technology and the final stage of evaluation and audit. Trends from the literature and the questionnaires were examined in the context of New Zealand organisations. Structured interviews were conducted with these organisations. The results of the investigation form the success factors with discussion on the necessary planning, implementation and evaluation for businesses wishing to embrace the medium. As 94% of New Zealand business are small and medium sized enterprises (SMEs), the majority of findings are relevant to that context in particular although a number can be extrapolated to Internet-connected organisations in general. Three objectives run through the various research phases. The research objectives are: - to identify the nature and extent of Internet based business activities by organisations in New Zealand - to examine the motives and impacts of these initiatives - to determine factors that contribute to the success of these endeavours The first research phase focusses on the planning issues including perceived and actual information needs of organisations using the Internet. The process of selecting appropriate technology and Internet providers is considered and study made of the competitive advantage offered by the Internet. Implications for organisations such as knowledge gaps, changing power structures with new technology and issues of privacy and controls are also considered. Implications for individuals including workload, communication patterns, training, reskilling and deskilling are pursued. The second research phase focusses on the acquisition and implementation of the Internet by organisations. Comparisons are made between organisations and their strategies for getting online and managing the process of changeover and transition to an Internet-based business environment. The third research phase compares expected and actual outcomes from Internet implementation in organisations. A review is carried out with participating organisations by examining the role of the Internet on business effectiveness. The area of Internet use in organisations needs investigation as the majority are faced with devising an Internet strategy, yet most companies have barely considered the online world till relatively recently. This research considers the implications of this for successful Internet use and presents success factors for organisations. The recent downturn in dot.coms has increased interest in the factors determining success although the cases included in this thesis are not dot.coms as such but ordinary businesses that want to use the Internet.