The increased complexity, heterogeneity and the dynamism of networked systems and applications make current configuration and management tools to be ineffective. A new paradigm to dynamically configure and manage large-scale complex and heterogeneous networked systems is critically needed. In this dissertation, we present a self configuration paradigm based on the principles of autonomic computing that can handle efficiently complexity, dynamism and uncertainty in configuring networked systems and their applications. Our approach is based on making any resource/application to operate as an Autonomic Component (that means, it can be self-configured, self-healed, self-optimized and self-protected) by using two software modules: Component Management Interface (CMI) to specify the configuration and operational policies associated with each component and Component Runtime Manager (CRM) that manages the component configurations and operations using the policies defined in CMI. We use several configuration metrics (adaptability, complexity, latency, scalability, overhead, and effectiveness) to evaluate the effectiveness of our self-configuration approach when compared to other configuration techniques. We have used our approach to dynamically configure four systems: Automatic IT system management, Dynamic security configuration of networked systems, Self-management of data backup and disaster recovery system and Automatic security patches download and installation on a large scale test bed. Our experimental results showed that by applying our self-configuration approach, the initial configuration time, the initial configuration complexity and the dynamic configuration complexity can be reduced significantly. For example, the configuration time for security patches download and installation on nine machines is reduced to 4399 seconds from 27193 seconds. Furthermore our system provides most adaptability (e.g., 100% for Snort rule set configuration) comparing to hard coded approach (e.g., 22% for Snort rule set configuration) and can improve the performance of managed system greatly. For example, in data backup and recovery system, our approach can reduce the total cost by 54.1% when network bandwidth decreases. In addition, our framework is scalable and imposes very small overhead (less than 1%) on the managed system.

With a fixed number of terminals and a fixed system spectrum, it can be shown that increasing the number of BSs in a cellular network results in a better network performance. However, a regular organized deployment of a cellular network with small cells is both prohibitively expensive and complicated. A possible solution is to allow the network to grow in an organic fashion. This calls for self-configurable approaches for resource allocation which not only improve the performance but also decrease the network planning as well as maintenance costs. Over the past few years, a particular type of small BSs known as femto-BSs has attracted tremendous attention from the industry and academia alike. Femto BSs operate on the licensed spectrum allocated to the cellular network. They are small, inexpensive and transmit at low power levels. Although the deployment of these small BSs result in significant improvements in the indoor coverage for both voice and data services, they only satisfy the immediate needs of the present cellular networks — namely the improvement of the indoor coverage. They do not provide a fundamental solution for a scalable architecture which can organically grow and adapt to the short and long term changes in the network. In this thesis, we propose a practical unified framework for the system design and resource allocation of cellular networks with various types of base stations (with different power budgets) deployed in an irregular fashion. We refer to these networks as autonomous cellular networks. To this end, we first introduce an adaptive localized approach to resource allocation in traditional cellular networks. We show that localized resource assignment at the cost of partial loss of orthogonality at the cell edges can provide significant gains in the network performance. In the second part of the thesis, we propose an adaptive self-configurable resource allocation framework for cellular networks. A network clustering technique is proposed which enables coordinated resource allocation in a network with irregular deployment of BSs. The performance of the proposed framework is evaluated with the regular as well as the irregular deployment of BSs.

With a fixed number of terminals and a fixed system spectrum, it can be shown that increasing the number of BSs in a cellular network results in a better network performance. However, a regular organized deployment of a cellular network with small cells is both prohibitively expensive and complicated. A possible solution is to allow the network to grow in an organic fashion. This calls for self-configurable approaches for resource allocation which not only improve the performance but also decrease the network planning as well as maintenance costs. Over the past few years, a particular type of small BSs known as femto-BSs has attracted tremendous attention from the industry and academia alike. Femto BSs operate on the licensed spectrum allocated to the cellular network. They are small, inexpensive and transmit at low power levels. Although the deployment of these small BSs result in significant improvements in the indoor coverage for both voice and data services, they only satisfy the immediate needs of the present cellular networks — namely the improvement of the indoor coverage. They do not provide a fundamental solution for a scalable architecture which can organically grow and adapt to the short and long term changes in the network. In this thesis, we propose a practical unified framework for the system design and resource allocation of cellular networks with various types of base stations (with different power budgets) deployed in an irregular fashion. We refer to these networks as autonomous cellular networks. To this end, we first introduce an adaptive localized approach to resource allocation in traditional cellular networks. We show that localized resource assignment at the cost of partial loss of orthogonality at the cell edges can provide significant gains in the network performance. In the second part of the thesis, we propose an adaptive self-configurable resource allocation framework for cellular networks. A network clustering technique is proposed which enables coordinated resource allocation in a network with irregular deployment of BSs. The performance of the proposed framework is evaluated with the regular as well as the irregular deployment of BSs.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In this paper, we propose a receiver design for satellite ground station use which can demodulate a waveform without specific knowledge of the data rate, convolutional code rate, or line code used. Several assumptions, consistent with the Space Network operating environment, are made including only certain data rates, convolutional code rates and generator polynomials, and types of line encoders. Despite the assumptions, a wide class of digital signaling (covering most of what might be seen at a ground station receiver) is captured. The approach uses standard signal processing techniques to identify data rate and line encoder class and a look up table with coded sync words (a standard feature of telemetry data frame header) in order to identify the key parameters. As our research has shown, the leading bits of the received coded frame can be used to uniquely identify the parameters. With proper identification, a basic receiver autoconfiguration sequence (date rate, line decoder, convolutional decoder) may be constructed.

The use of wireless radio technology is well established for narrowband access systems, but its use for broadband access is relatively new. Wireless mesh architecture is a first step towards providing high-bandwidth wireless network coverage, spectral efficiency, and economic advantage. However, the widespread adoption and use of Wireless Mesh Networks (WMN) as a backbone for large wireless access networks and for last-mile subscriber access is heavily dependent on the technology’s ease of deployment. In order for WMNs to be regarded as mainstream technology, it needs to gain a competitive edge compared to wireline technologies such as DSL and cable. To achieve this, a broadband wireless network must be self-configuring, self-healing and self-organizing. In this thesis, we address these challenges. First, we propose a four-stage scheme (power-up, bootstrapping, network registration, and network optimization). We develop algorithms for each of these stages, taking advantage of the inherent properties of WMNs to determine the network’s topology. The novel part of our scheme is in the de-coupling of the subscriber’s credentials from the network hardware. This is a key part of our architecture as it helps ensure quick network enrolment, management and portability. It also helps, in our opinion, make the concept of widespread deployment using commodity hardware feasible.

The use of wireless radio technology is well established for narrowband access systems, but its use for broadband access is relatively new. Wireless mesh architecture is a first step towards providing high-bandwidth wireless network coverage, spectral efficiency, and economic advantage. However, the widespread adoption and use of Wireless Mesh Networks (WMN) as a backbone for large wireless access networks and for last-mile subscriber access is heavily dependent on the technology’s ease of deployment. In order for WMNs to be regarded as mainstream technology, it needs to gain a competitive edge compared to wireline technologies such as DSL and cable. To achieve this, a broadband wireless network must be self-configuring, self-healing and self-organizing. In this thesis, we address these challenges. First, we propose a four-stage scheme (power-up, bootstrapping, network registration, and network optimization). We develop algorithms for each of these stages, taking advantage of the inherent properties of WMNs to determine the network’s topology. The novel part of our scheme is in the de-coupling of the subscriber’s credentials from the network hardware. This is a key part of our architecture as it helps ensure quick network enrolment, management and portability. It also helps, in our opinion, make the concept of widespread deployment using commodity hardware feasible.

Made available in DSpace on 2014-06-12T15:52:19Z (GMT). No. of bitstreams: 2 arquivo3230_1.pdf: 3857855 bytes, checksum: 68166824b668991a7746113795017a33 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Universidade Federal de Campina Grande / Nos últimos anos diversas tecnologias foram desenvolvidas com o objetivo de facilitar a interação entre os usuários e seus dispositivos e melhorar a comunicação entre eles, necessitando da interoperabilidade entre essas tecnologias e, consequentemente, a necessidade de uma nova infraestrutura de rede que permita uma melhor adaptação aos novos requisitos criados por esta diversidade de tecnologias. O modelo de comunicação entre redes também está sendo modificado, uma vez que é esperado que elas sejam criadas dinamicamente para facilitar a utilização da rede pelos usuários e permitir que diversas operações sejam realizadas automaticamente (endereçamento, descoberta de serviços, etc.). Essas redes devem estar presentes em diversos cenários de comunicação e um dos seus principais desafios é permitir que diversos tipos de tecnologias cooperem em ambientes com alto dinamismo e heterogeneidade. Estas redes têm como objetivo interconectar diferentes tecnologias e domínios oferecendo uma comunicação que aparente ser homogêneo para os seus usuários. Para a criação dessas futuras redes dinâmicas pontos chaves são a interconexão e a cooperação entre as tecnologias envolvidas, o que exige o desenvolvimento de soluções para garantir que novos requisitos sejam suportados. Para permitir que novos requisitos sejam corretamente suportados, um conjunto de mecanismos para controlar a descoberta automática de recursos e realizar a sua configuração é proposto, permitindo que redes sejam criadas e adaptadas de maneira completamente automática. Também é proposto um mecanismo de negociação de políticas inter-domínio responsável por descobrir e negociar novos recursos que dever ser usados pelas redes, o que traz um novo modelo de comunicação baseado na criação oportunista de redes e ao mesmo tempo permite a criação de novos acordos de comunicação entre domínios administrativos de maneira dinâmica e sem a intervenção dos usuários ou dos administradores das redes

Humans are relational beings, as they are constantly in interaction with others and with their environment. In schools, learners spend at least nine years of their lives in formal schooling, and the relationships they have with their teachers are bound to have an impact on their self-configuration. According to the Field theory, the Bioecological theory and the Dialogical theory of self, which were used as theoretical frameworks for this study, individuals’ self-configuration is impacted by their environment, experiences and interactions with others. The focus of this study was on Grade 7 learners’ self-configuration experiences within the teacher-learner relationship. Grade 7 learners are at the beginning of the adolescent phase, which is characterised by many changes, transitions, challenges and uncertainties. One of these transitions is the forthcoming transition from primary school to high school and a healthy self-configuration could assist learners to adapt to these changes in a positive manner. The research was qualitative in nature and made use of the case study method. This allowed the researcher to use data gathering approaches through which the subjective experiences of the participants could be explored. Twelve participants volunteered to take part in this study, and data was gathered by means of individual interviews as well as group discussions. All interviews and group discussions were voice and video recorded, where after they were transcribed and analysed by means of thematic analysis. The analysis allowed for data to be organised into meaningful themes. It was found that learners’ experiences of relationships with teachers are both positive and negative. Self-regulation in learners takes place through encouragement and disapproval from teachers, as well as through lessons learnt from teachers and from past experiences. Further studies around self-configuration and teacher-learner relationships are recommended, in order to make teachers more aware of the importance of the teacher-learner relationship, and also to determine what the obstacles are in developing supportive and caring teacher-learner relationships. By highlighting the importance, and by determining the obstacles, more meaningful teacher-learner relationships could be encouraged and developed in order to enhance learners’ self-configuration experiences. / MA (Psychology), North-West University, Potchefstroom Campus, 2015

Challenging behaviour poses problems for teachers globally and yet very little research has been done with regard to the teacher-learner relationship and what challenging behaviour does to the teacher. The goal of this study was to explore teachers’ experiences of challenging behaviour within their relationships with learners that display challenging behaviour regarding teacher’s self-configuration. A qualitative approach was pursued in the form of an interpretive descriptive design in order to gain a better understanding of the teachers’ self-configuration experiences. For the purpose of this study the field theory was used as the theoretical framework, viewing teachers in their environment, specifically focusing on the teacher-learner relationship. A total of 12 teachers were purposefully selected from a school in Observatory, Johannesburg. The data were collected through in-depth interviews. Additionally, incomplete sentences were used to enrich data and to enhance trustworthiness. Triangulation was ensured by using two data collection methods to increase the credibility and validity of the results. The interviews and incomplete sentences were recorded via audio recording equipment. The recordings were then transcribed in order to identify emerging themes and subthemes. Thematic analysis was used once the data had been transcribed in order to gain meaningful information. This study revealed teachers’ self-configuration experiences in their relationships with learners with challenging behaviour and experienced their relationships with these children as a foundation for self-configuration. Teachers’ self-configuration is embedded in their different selves at school and their love and passion for teaching are reduced due to negative emotions. Experiences within the relationship escalate to the home environment and challenging behaviour causes stress for teachers. Teachers viewed challenging behaviour as behaviour that is an internal challenge for the learner, but also behaviour that is directed externally towards the teacher and other learners. Trust and respect, class size, individual attention and communication were identified elements contributing to self-configuration within the teacher-learner relationship. This study showed the importance of relationships in the school context and specifically focused on teachers’ self-configuration. / MA (Psychology), North-West University, Potchefstroom Campus, 2015

More often than not learners with learning difficulties are treated differently from normal mainstream learners. Often they experience themselves in a less positive manner because of the interactions with various teachers who may not always have enough patience to deal with these learners while trying to cope with large numbers of learners on a daily base. This study was conducted to explore self-configuration experiences of Intermediate Phase learners with learning difficulties within the learner-teacher relationship. Literature indicates that the self is a complex construct to define and can be interpreted in various ways. The researcher aimed to understand how the self is configured in experiences that learners have with their teachers and how these experiences contribute to and affect self-configuration. The theoretical frameworks of the Dialogical Theory of Self and the Gestalt Field Theory were used to gain an understanding of how vital relations and context are in the configuration experiences of the self. A qualitative case study with purposive sampling was conducted. The study was done at a single school where all the learners in the school have learning difficulties. There were nine learners that fell in the Intermediate Phase category and all of them were boys who voluntarily participated in the research. Data were collected by means of a semi-structured interview in which the participants were asked to use incomplete sentences and a visual map that they made to help them express their experiences. A follow-up interview was conducted to check that the meaning that the learner ascribed to his incomplete sentences and visual map was accurate and an opportunity was given to add something should the participant want to. Participants were given this opportunity as some of them had difficulty in expressing themselves adequately during the first session as a result of their learning difficulties in so much as they struggle to find words that express their feelings and what they wanted to communicate. Data were transcribed and analysed by means of thematic analysis. The study indicated that it was aspects such as quality time the teachers spent with the learners and the tone of voice of the teacher that contributed to the self-configuration experiences of the learners. Further research is necessary to determine whether this is the experience in other schools that cater for learners with learning difficulties and how this knowledge may be used to bring greater awareness to teachers to better understand how learners experience their relationship with regards to self-configuration. Quantitative studies can also be conducted to investigate the impact of teacher-learner relationships on self-configuration. / MA (Psychology), North-West University, Potchefstroom Campus, 2015