A framework for interpreting noisy, two-dimensional images, based on a fuzzification of programmed, attributed graph grammars
- Authors: Watkins, Gregory Shroll
- Date: 1998
- Subjects: Music -- Data processing Computer sound processing Artificial intelligence -- Musical applications Fuzzy systems
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4604 , http://hdl.handle.net/10962/d1004862
- Description: This thesis investigates a fuzzy syntactic approach to the interpretation of noisy two-dimensional images. This approach is based on a modification of the attributed graph grammar formalism to utilise fuzzy membership functions in the applicability predicates. As far as we are aware, this represents the first such modification of graph grammars. Furthermore, we develop a method for programming the resultant fuzzy attributed graph grammars through the use of non-deterministic control diagrams. To do this, we modify the standard programming mechanism to allow it to cope with the fuzzy certainty values associated with productions in our grammar. Our objective was to develop a flexible framework which can be used for the recognition of a wide variety of image classes, and which is adept at dealing with noise in these images. Programmed graph grammars are specifically chosen for the ease with which they allow one to specify a new two-dimensional image class. We implement a prototype system for Optical Music Recognition using our framework. This system allows us to test the capabilities of the framework for coping with noise in the context of handwritten music score recognition. Preliminary results from the prototype system show that the framework copes well with noisy images.
- Full Text:
- Date Issued: 1998
- Authors: Watkins, Gregory Shroll
- Date: 1998
- Subjects: Music -- Data processing Computer sound processing Artificial intelligence -- Musical applications Fuzzy systems
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4604 , http://hdl.handle.net/10962/d1004862
- Description: This thesis investigates a fuzzy syntactic approach to the interpretation of noisy two-dimensional images. This approach is based on a modification of the attributed graph grammar formalism to utilise fuzzy membership functions in the applicability predicates. As far as we are aware, this represents the first such modification of graph grammars. Furthermore, we develop a method for programming the resultant fuzzy attributed graph grammars through the use of non-deterministic control diagrams. To do this, we modify the standard programming mechanism to allow it to cope with the fuzzy certainty values associated with productions in our grammar. Our objective was to develop a flexible framework which can be used for the recognition of a wide variety of image classes, and which is adept at dealing with noise in these images. Programmed graph grammars are specifically chosen for the ease with which they allow one to specify a new two-dimensional image class. We implement a prototype system for Optical Music Recognition using our framework. This system allows us to test the capabilities of the framework for coping with noise in the context of handwritten music score recognition. Preliminary results from the prototype system show that the framework copes well with noisy images.
- Full Text:
- Date Issued: 1998
A knowledge-oriented, context-sensitive architectural framework for service deployment in marginalized rural communities
- Authors: Thinyane, Mamello P
- Date: 2009
- Subjects: Information technology Expert systems (Computer science) Software architecture User interfaces (Computer systems) Ethnoscience Social networks Rural development Technical assistance -- Developing countries Information networks -- Developing countries
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4599 , http://hdl.handle.net/10962/d1004843
- Description: The notion of a global knowledge society is somewhat of a misnomer due to the fact that large portions of the global community are not participants in this global knowledge society which is driven, shaped by and socio-technically biased towards a small fraction of the global population. Information and Communication Technology (ICT) is culture-sensitive and this is a dynamic that is largely ignored in the majority of ICT for Development (ICT4D) interventions, leading to the technological determinism flaw and ultimately a failure of the undertaken projects. The deployment of ICT solutions, in particular in the context of ICT4D, must be informed by the cultural and socio-technical profile of the deployment environments and solutions themselves must be developed with a focus towards context-sensitivity and ethnocentricity. In this thesis, we investigate the viability of a software architectural framework for the development of ICT solutions that are context-sensitive and ethnocentric1, and so aligned with the cultural and social dynamics within the environment of deployment. The conceptual framework, named PIASK, defines five tiers (presentation, interaction, access, social networking, and knowledge base) which allow for: behavioural completeness of the layer components; a modular and functionally decoupled architecture; and the flexibility to situate and contextualize the developed applications along the dimensions of the User Interface (UI), interaction modalities, usage metaphors, underlying Indigenous Knowledge (IK), and access protocols. We have developed a proof-of-concept service platform, called KnowNet, based on the PIASK architecture. KnowNet is built around the knowledge base layer, which consists of domain ontologies that encapsulate the knowledge in the platform, with an intrinsic flexibility to access secondary knowledge repositories. The domain ontologies constructed (as examples) are for the provisioning of eServices to support societal activities (e.g. commerce, health, agriculture, medicine) within a rural and marginalized area of Dwesa, in the Eastern Cape province of South Africa. The social networking layer allows for situating the platform within the local social systems. Heterogeneity of user profiles and multiplicity of end-user devices are handled through the access and the presentation components, and the service logic is implemented by the interaction components. This services platform validates the PIASK architecture for end-to-end provisioning of multi-modal, heterogeneous, ontology-based services. The development of KnowNet was informed on one hand by the latest trends within service architectures, semantic web technologies and social applications, and on the other hand by the context consideration based on the profile (IK systems dynamics, infrastructure, usability requirements) of the Dwesa community. The realization of the service platform is based on the JADE Multi-Agent System (MAS), and this shows the applicability and adequacy of MAS’s for service deployment in a rural context, at the same time providing key advantages such as platform fault-tolerance, robustness and flexibility. While the context of conceptualization of PIASK and the implementation of KnowNet is that of rurality and of ICT4D, the applicability of the architecture extends to other similarly heterogeneous and context-sensitive domains. KnowNet has been validated for functional and technical adequacy, and we have also undertaken an initial prevalidation for social context sensitivity. We observe that the five tier PIASK architecture provides an adequate framework for developing context-sensitive and ethnocentric software: by functionally separating and making explicit the social networking and access tier components, while still maintaining the traditional separation of presentation, business logic and data components.
- Full Text:
- Date Issued: 2009
- Authors: Thinyane, Mamello P
- Date: 2009
- Subjects: Information technology Expert systems (Computer science) Software architecture User interfaces (Computer systems) Ethnoscience Social networks Rural development Technical assistance -- Developing countries Information networks -- Developing countries
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4599 , http://hdl.handle.net/10962/d1004843
- Description: The notion of a global knowledge society is somewhat of a misnomer due to the fact that large portions of the global community are not participants in this global knowledge society which is driven, shaped by and socio-technically biased towards a small fraction of the global population. Information and Communication Technology (ICT) is culture-sensitive and this is a dynamic that is largely ignored in the majority of ICT for Development (ICT4D) interventions, leading to the technological determinism flaw and ultimately a failure of the undertaken projects. The deployment of ICT solutions, in particular in the context of ICT4D, must be informed by the cultural and socio-technical profile of the deployment environments and solutions themselves must be developed with a focus towards context-sensitivity and ethnocentricity. In this thesis, we investigate the viability of a software architectural framework for the development of ICT solutions that are context-sensitive and ethnocentric1, and so aligned with the cultural and social dynamics within the environment of deployment. The conceptual framework, named PIASK, defines five tiers (presentation, interaction, access, social networking, and knowledge base) which allow for: behavioural completeness of the layer components; a modular and functionally decoupled architecture; and the flexibility to situate and contextualize the developed applications along the dimensions of the User Interface (UI), interaction modalities, usage metaphors, underlying Indigenous Knowledge (IK), and access protocols. We have developed a proof-of-concept service platform, called KnowNet, based on the PIASK architecture. KnowNet is built around the knowledge base layer, which consists of domain ontologies that encapsulate the knowledge in the platform, with an intrinsic flexibility to access secondary knowledge repositories. The domain ontologies constructed (as examples) are for the provisioning of eServices to support societal activities (e.g. commerce, health, agriculture, medicine) within a rural and marginalized area of Dwesa, in the Eastern Cape province of South Africa. The social networking layer allows for situating the platform within the local social systems. Heterogeneity of user profiles and multiplicity of end-user devices are handled through the access and the presentation components, and the service logic is implemented by the interaction components. This services platform validates the PIASK architecture for end-to-end provisioning of multi-modal, heterogeneous, ontology-based services. The development of KnowNet was informed on one hand by the latest trends within service architectures, semantic web technologies and social applications, and on the other hand by the context consideration based on the profile (IK systems dynamics, infrastructure, usability requirements) of the Dwesa community. The realization of the service platform is based on the JADE Multi-Agent System (MAS), and this shows the applicability and adequacy of MAS’s for service deployment in a rural context, at the same time providing key advantages such as platform fault-tolerance, robustness and flexibility. While the context of conceptualization of PIASK and the implementation of KnowNet is that of rurality and of ICT4D, the applicability of the architecture extends to other similarly heterogeneous and context-sensitive domains. KnowNet has been validated for functional and technical adequacy, and we have also undertaken an initial prevalidation for social context sensitivity. We observe that the five tier PIASK architecture provides an adequate framework for developing context-sensitive and ethnocentric software: by functionally separating and making explicit the social networking and access tier components, while still maintaining the traditional separation of presentation, business logic and data components.
- Full Text:
- Date Issued: 2009
A mobile phone solution for ad-hoc hitch-hiking in South Africa
- Authors: Miteche, Sacha Patrick
- Date: 2014
- Subjects: Cell phones -- Information services , Cell phone users -- South Africa , Hitchhiking -- South Africa , Mobile communication systems -- Social aspects , Digital media -- South Africa , Information technology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4702 , http://hdl.handle.net/10962/d1013340
- Description: The purpose of this study was to investigate the use of mobile phones in organizing ad-hoc vehicle ridesharing based on hitch-hiking trips involving private car drivers and commuters in South Africa. A study was conducted to learn how hitch-hiking trips are arranged in the urban and rural areas of the Eastern Cape. This involved carrying out interviews with hitch-hikers and participating in several trips. The study results provided the design specifications for a Dynamic Ridesharing System (DRS) tailor-made to the hitch-hiking culture of this context. The design of the DRS considered the delivery of the ad-hoc ridesharing service to the anticipated mobile phones owned by people who use hitch-hiking. The implementation of the system used the available open source solutions and guidelines under the Siyakhula Living Lab project, which promotes the use of Information and Communication Technology (ICT) in marginalized communities of South Africa. The developed prototype was tested in both the simulated and live environments, then followed by usability tests to establish the viability of the system. The results from the tests indicate an initial breakthrough in the process of modernizing the ad-hoc ridesharing of hitch-hiking which is used by a section of people in the urban and rural areas of South Africa.
- Full Text:
- Date Issued: 2014
- Authors: Miteche, Sacha Patrick
- Date: 2014
- Subjects: Cell phones -- Information services , Cell phone users -- South Africa , Hitchhiking -- South Africa , Mobile communication systems -- Social aspects , Digital media -- South Africa , Information technology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4702 , http://hdl.handle.net/10962/d1013340
- Description: The purpose of this study was to investigate the use of mobile phones in organizing ad-hoc vehicle ridesharing based on hitch-hiking trips involving private car drivers and commuters in South Africa. A study was conducted to learn how hitch-hiking trips are arranged in the urban and rural areas of the Eastern Cape. This involved carrying out interviews with hitch-hikers and participating in several trips. The study results provided the design specifications for a Dynamic Ridesharing System (DRS) tailor-made to the hitch-hiking culture of this context. The design of the DRS considered the delivery of the ad-hoc ridesharing service to the anticipated mobile phones owned by people who use hitch-hiking. The implementation of the system used the available open source solutions and guidelines under the Siyakhula Living Lab project, which promotes the use of Information and Communication Technology (ICT) in marginalized communities of South Africa. The developed prototype was tested in both the simulated and live environments, then followed by usability tests to establish the viability of the system. The results from the tests indicate an initial breakthrough in the process of modernizing the ad-hoc ridesharing of hitch-hiking which is used by a section of people in the urban and rural areas of South Africa.
- Full Text:
- Date Issued: 2014
A mobile toolkit and customised location server for the creation of cross-referencing location-based services
- Ndakunda, Shange-Ishiwa Tangeni
- Authors: Ndakunda, Shange-Ishiwa Tangeni
- Date: 2013
- Subjects: Location-based services -- Security measures , Mobile communication systems -- Security measures , Digital communications , Java (Computer program language) , Application software -- Development -- Computer programs , User interfaces (Computer systems)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4703 , http://hdl.handle.net/10962/d1013604
- Description: Although there are several Software Development kits and Application Programming Interfaces for client-side location-based services development, they mostly involve the creation of self-referencing location-based services. Self-referencing location-based services include services such as geocoding, reverse geocoding, route management and navigation which focus on satisfying the location-based requirements of a single mobile device. There is a lack of open-source Software Development Kits for the development of client-side location-based services that are cross-referencing. Cross-referencing location-based services are designed for the sharing of location information amongst different entities on a given network. This project was undertaken to assemble, through incremental prototyping, a client-side Java Micro Edition location-based services Software Development Kit and a Mobicents location server to aid mobile network operators and developers alike in the quick creation of the transport and privacy protection of cross-referencing location-based applications on Session Initiation Protocol bearer networks. The privacy of the location information is protected using geolocation policies. Developers do not need to have an understanding of Session Initiation Protocol event signaling specifications or of the XML Configuration Access Protocol to use the tools that we put together. The developed tools are later consolidated using two sample applications, the friend-finder and child-tracker services. Developer guidelines are also provided, to aid in using the provided tools.
- Full Text:
- Date Issued: 2013
- Authors: Ndakunda, Shange-Ishiwa Tangeni
- Date: 2013
- Subjects: Location-based services -- Security measures , Mobile communication systems -- Security measures , Digital communications , Java (Computer program language) , Application software -- Development -- Computer programs , User interfaces (Computer systems)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4703 , http://hdl.handle.net/10962/d1013604
- Description: Although there are several Software Development kits and Application Programming Interfaces for client-side location-based services development, they mostly involve the creation of self-referencing location-based services. Self-referencing location-based services include services such as geocoding, reverse geocoding, route management and navigation which focus on satisfying the location-based requirements of a single mobile device. There is a lack of open-source Software Development Kits for the development of client-side location-based services that are cross-referencing. Cross-referencing location-based services are designed for the sharing of location information amongst different entities on a given network. This project was undertaken to assemble, through incremental prototyping, a client-side Java Micro Edition location-based services Software Development Kit and a Mobicents location server to aid mobile network operators and developers alike in the quick creation of the transport and privacy protection of cross-referencing location-based applications on Session Initiation Protocol bearer networks. The privacy of the location information is protected using geolocation policies. Developers do not need to have an understanding of Session Initiation Protocol event signaling specifications or of the XML Configuration Access Protocol to use the tools that we put together. The developed tools are later consolidated using two sample applications, the friend-finder and child-tracker services. Developer guidelines are also provided, to aid in using the provided tools.
- Full Text:
- Date Issued: 2013
A model for a context aware machine-based personal memory manager and its implementation using a visual programming environment
- Authors: Tsegaye, Melekam Asrat
- Date: 2007
- Subjects: Visual programming (Computer science) Memory management (Computer science) Memory -- Data processing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4640 , http://hdl.handle.net/10962/d1006563
- Description: Memory is a part of cognition. It is essential for an individual to function normally in society. It encompasses an individual's lifetime experience, thus defining his identity. This thesis develops the concept of a machine-based personal memory manager which captures and manages an individual's day-to-day external memories. Rather than accumulating large amounts of data which has to be mined for useful memories, the machine-based memory manager automatically organizes memories as they are captured to enable their quick retrieval and use. The main functions of the machine-based memory manager envisioned in this thesis are the support and the augmentation of an individual's biological memory system. In the thesis, a model for a machine-based memory manager is developed. A visual programming environment, which can be used to build context aware applications as well as a proof-of-concept machine-based memory manager, is conceptualized and implemented. An experimental machine-based memory manager is implemented and evaluated. The model describes a machine-based memory manager which manages an individual's external memories by context. It addresses the management of external memories which accumulate over long periods of time by proposing a context aware file system which automatically organizes external memories by context. It describes how personal memory management can be facilitated by machine using six entities (life streams, memory producers, memory consumers, a memory manager, memory fragments and context descriptors) and the processes in which these entities participate (memory capture, memory encoding and decoding, memory decoding and retrieval). The visual programming environment represents a development tool which contains facilities that support context aware application programming. For example, it provides facilities which enable the definition and use of virtual sensors. It enables rapid programming with a focus on component re-use and dynamic composition of applications through a visual interface. The experimental machine-based memory manager serves as an example implementation of the machine-based memory manager which is described by the model developed in this thesis. The hardware used in its implementation consists of widely available components such as a camera, microphone and sub-notebook computer which are assembled in the form of a wearable computer. The software is constructed using the visual programming environment developed in this thesis. It contains multiple sensor drivers, context interpreters, a context aware file system as well as memory retrieval and presentation interfaces. The evaluation of the machine-based memory manager shows that it is possible to create a machine which monitors the states of an individual and his environment, and manages his external memories, thus supporting and augmenting his biological memory.
- Full Text:
- Date Issued: 2007
- Authors: Tsegaye, Melekam Asrat
- Date: 2007
- Subjects: Visual programming (Computer science) Memory management (Computer science) Memory -- Data processing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4640 , http://hdl.handle.net/10962/d1006563
- Description: Memory is a part of cognition. It is essential for an individual to function normally in society. It encompasses an individual's lifetime experience, thus defining his identity. This thesis develops the concept of a machine-based personal memory manager which captures and manages an individual's day-to-day external memories. Rather than accumulating large amounts of data which has to be mined for useful memories, the machine-based memory manager automatically organizes memories as they are captured to enable their quick retrieval and use. The main functions of the machine-based memory manager envisioned in this thesis are the support and the augmentation of an individual's biological memory system. In the thesis, a model for a machine-based memory manager is developed. A visual programming environment, which can be used to build context aware applications as well as a proof-of-concept machine-based memory manager, is conceptualized and implemented. An experimental machine-based memory manager is implemented and evaluated. The model describes a machine-based memory manager which manages an individual's external memories by context. It addresses the management of external memories which accumulate over long periods of time by proposing a context aware file system which automatically organizes external memories by context. It describes how personal memory management can be facilitated by machine using six entities (life streams, memory producers, memory consumers, a memory manager, memory fragments and context descriptors) and the processes in which these entities participate (memory capture, memory encoding and decoding, memory decoding and retrieval). The visual programming environment represents a development tool which contains facilities that support context aware application programming. For example, it provides facilities which enable the definition and use of virtual sensors. It enables rapid programming with a focus on component re-use and dynamic composition of applications through a visual interface. The experimental machine-based memory manager serves as an example implementation of the machine-based memory manager which is described by the model developed in this thesis. The hardware used in its implementation consists of widely available components such as a camera, microphone and sub-notebook computer which are assembled in the form of a wearable computer. The software is constructed using the visual programming environment developed in this thesis. It contains multiple sensor drivers, context interpreters, a context aware file system as well as memory retrieval and presentation interfaces. The evaluation of the machine-based memory manager shows that it is possible to create a machine which monitors the states of an individual and his environment, and manages his external memories, thus supporting and augmenting his biological memory.
- Full Text:
- Date Issued: 2007
A review of the Siyakhula Living Lab’s network solution for Internet in marginalized communities
- Muchatibaya, Hilbert Munashe
- Authors: Muchatibaya, Hilbert Munashe
- Date: 2022-10-14
- Subjects: Information and communication technologies for development , Information technology South Africa , Access network , User experience , Local area networks (Computer networks) South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/364943 , vital:65664
- Description: Changes within Information and Communication Technology (ICT) over the past decade required a review of the network layer component deployed in the Siyakhula Living Lab (SLL), a long-term joint venture between the Telkom Centres of Excellence hosted at University of Fort Hare and Rhodes University in South Africa. The SLL overall solution for the sustainable internet in poor communities consists of three main components – the computing infrastructure layer, the network layer, and the e-services layer. At the core of the network layer is the concept of BI, a high-speed local area network realized through easy-to deploy wireless technologies that establish point-to-multipoint connections among schools within a limited geographical area. Schools within the broadband island become then Digital Access Nodes (DANs), with computing infrastructure that provides access to the network. The review, reported in this thesis, aimed at determining whether the model for the network layer was still able to meet the needs of marginalized communities in South Africa, given the recent changes in ICT. The research work used the living lab methodology – a grassroots, user-driven approach that emphasizes co-creation between the beneficiaries and external entities (researchers, industry partners and the government) - to do viability tests on the solution for the network component. The viability tests included lab and field experiments, to produce the qualitative and quantitative data needed to propose an updated blueprint. The results of the review found that the network topology used in the SLL’s network, the BI, is still viable, while WiMAX is now outdated. Also, the in-network web cache, Squid, is no longer effective, given the switch to HTTPS and the pervasive presence of advertising. The solution to the first issue is outdoor Wi-Fi, a proven solution easily deployable in grass-roots fashion. The second issue can be mitigated by leveraging Squid’s ‘bumping’ and splicing features; deploying a browser extension to make picture download optional; and using Pihole, a DNS sinkhole. Hopefully, the revised solution could become a component of South African Government’s broadband plan, “SA Connect”. , Thesis (MSc) -- Faculty of Science, Computer Science, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Muchatibaya, Hilbert Munashe
- Date: 2022-10-14
- Subjects: Information and communication technologies for development , Information technology South Africa , Access network , User experience , Local area networks (Computer networks) South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/364943 , vital:65664
- Description: Changes within Information and Communication Technology (ICT) over the past decade required a review of the network layer component deployed in the Siyakhula Living Lab (SLL), a long-term joint venture between the Telkom Centres of Excellence hosted at University of Fort Hare and Rhodes University in South Africa. The SLL overall solution for the sustainable internet in poor communities consists of three main components – the computing infrastructure layer, the network layer, and the e-services layer. At the core of the network layer is the concept of BI, a high-speed local area network realized through easy-to deploy wireless technologies that establish point-to-multipoint connections among schools within a limited geographical area. Schools within the broadband island become then Digital Access Nodes (DANs), with computing infrastructure that provides access to the network. The review, reported in this thesis, aimed at determining whether the model for the network layer was still able to meet the needs of marginalized communities in South Africa, given the recent changes in ICT. The research work used the living lab methodology – a grassroots, user-driven approach that emphasizes co-creation between the beneficiaries and external entities (researchers, industry partners and the government) - to do viability tests on the solution for the network component. The viability tests included lab and field experiments, to produce the qualitative and quantitative data needed to propose an updated blueprint. The results of the review found that the network topology used in the SLL’s network, the BI, is still viable, while WiMAX is now outdated. Also, the in-network web cache, Squid, is no longer effective, given the switch to HTTPS and the pervasive presence of advertising. The solution to the first issue is outdoor Wi-Fi, a proven solution easily deployable in grass-roots fashion. The second issue can be mitigated by leveraging Squid’s ‘bumping’ and splicing features; deploying a browser extension to make picture download optional; and using Pihole, a DNS sinkhole. Hopefully, the revised solution could become a component of South African Government’s broadband plan, “SA Connect”. , Thesis (MSc) -- Faculty of Science, Computer Science, 2022
- Full Text:
- Date Issued: 2022-10-14
A structural and functional specification of a SCIM for service interaction management and personalisation in the IMS
- Authors: Tsietsi, Mosiuoa Jeremia
- Date: 2012
- Subjects: Internet Protocol multimedia subsystem , Internet Protocol multimedia subsystem -- Specifications , Long-Term Evolution (Telecommunications) , European Telecommunications Standards Institute , Wireless communication systems , Multimedia communications
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4606 , http://hdl.handle.net/10962/d1004864 , Internet Protocol multimedia subsystem , Internet Protocol multimedia subsystem -- Specifications , Long-Term Evolution (Telecommunications) , European Telecommunications Standards Institute , Wireless communication systems , Multimedia communications
- Description: The Internet Protocol Multimedia Subsystem (IMS) is a component of the 3G mobile network that has been specified by standards development organisations such as the 3GPP (3rd Generation Partnership Project) and ETSI (European Telecommunication Standards Institute). IMS seeks to guarantee that the telecommunication network of the future provides subscribers with seamless access to services across disparate networks. In order to achieve this, it defines a service architecture that hosts application servers that provide subscribers with value added services. Typically, an application server bundles all the functionality it needs to execute the services it delivers, however this view is currently being challenged. It is now thought that services should be synthesised from simple building blocks called service capabilities. This decomposition would facilitate the re-use of service capabilities across multiple services and would support the creation of new services that could not have originally been conceived. The shift from monolithic services to those built from service capabilities poses a challenge to the current service model in IMS. To accommodate this, the 3GPP has defined an entity known as a service capability interaction manager (SCIM) that would be responsible for managing the interactions between service capabilities in order to realise complex services. Some of these interactions could potentially lead to undesirable results, which the SCIM must work to avoid. As an added requirement, it is believed that the network should allow policies to be applied to network services which the SCIM should be responsible for enforcing. At the time of writing, the functional and structural architecture of the SCIM has not yet been standardised. This thesis explores the current serv ice architecture of the IMS in detail. Proposals that address the structure and functions of the SCIM are carefully compared and contrasted. This investigation leads to the presentation of key aspects of the SCIM, and provides solutions that explain how it should interact with service capabilities, manage undesirable interactions and factor user and network operator policies into its execution model. A modified design of the IMS service layer that embeds the SCIM is subsequently presented and described. The design uses existing IMS protocols and requires no change in the behaviour of the standard IMS entities. In order to develop a testbed for experimental verification of the design, the identification of suitable software platforms was required. This thesis presents some of the most popular platforms currently used by developers such as the Open IMS Core and OpenSER, as well as an open source, Java-based, multimedia communication platform called Mobicents. As a precursor to the development of the SCIM, a converged multimedia service is presented that describes how a video streaming application that is leveraged by a web portal was implemented for an IMS testbed using Mobicents components. The Mobicents SIP Servlets container was subsequently used to model an initial prototype of the SCIM, using a mUlti-component telephony service to illustrate the proposed service execution model. The design focuses on SIP-based services only, but should also work for other types of IMS application servers as well.
- Full Text:
- Date Issued: 2012
- Authors: Tsietsi, Mosiuoa Jeremia
- Date: 2012
- Subjects: Internet Protocol multimedia subsystem , Internet Protocol multimedia subsystem -- Specifications , Long-Term Evolution (Telecommunications) , European Telecommunications Standards Institute , Wireless communication systems , Multimedia communications
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4606 , http://hdl.handle.net/10962/d1004864 , Internet Protocol multimedia subsystem , Internet Protocol multimedia subsystem -- Specifications , Long-Term Evolution (Telecommunications) , European Telecommunications Standards Institute , Wireless communication systems , Multimedia communications
- Description: The Internet Protocol Multimedia Subsystem (IMS) is a component of the 3G mobile network that has been specified by standards development organisations such as the 3GPP (3rd Generation Partnership Project) and ETSI (European Telecommunication Standards Institute). IMS seeks to guarantee that the telecommunication network of the future provides subscribers with seamless access to services across disparate networks. In order to achieve this, it defines a service architecture that hosts application servers that provide subscribers with value added services. Typically, an application server bundles all the functionality it needs to execute the services it delivers, however this view is currently being challenged. It is now thought that services should be synthesised from simple building blocks called service capabilities. This decomposition would facilitate the re-use of service capabilities across multiple services and would support the creation of new services that could not have originally been conceived. The shift from monolithic services to those built from service capabilities poses a challenge to the current service model in IMS. To accommodate this, the 3GPP has defined an entity known as a service capability interaction manager (SCIM) that would be responsible for managing the interactions between service capabilities in order to realise complex services. Some of these interactions could potentially lead to undesirable results, which the SCIM must work to avoid. As an added requirement, it is believed that the network should allow policies to be applied to network services which the SCIM should be responsible for enforcing. At the time of writing, the functional and structural architecture of the SCIM has not yet been standardised. This thesis explores the current serv ice architecture of the IMS in detail. Proposals that address the structure and functions of the SCIM are carefully compared and contrasted. This investigation leads to the presentation of key aspects of the SCIM, and provides solutions that explain how it should interact with service capabilities, manage undesirable interactions and factor user and network operator policies into its execution model. A modified design of the IMS service layer that embeds the SCIM is subsequently presented and described. The design uses existing IMS protocols and requires no change in the behaviour of the standard IMS entities. In order to develop a testbed for experimental verification of the design, the identification of suitable software platforms was required. This thesis presents some of the most popular platforms currently used by developers such as the Open IMS Core and OpenSER, as well as an open source, Java-based, multimedia communication platform called Mobicents. As a precursor to the development of the SCIM, a converged multimedia service is presented that describes how a video streaming application that is leveraged by a web portal was implemented for an IMS testbed using Mobicents components. The Mobicents SIP Servlets container was subsequently used to model an initial prototype of the SCIM, using a mUlti-component telephony service to illustrate the proposed service execution model. The design focuses on SIP-based services only, but should also work for other types of IMS application servers as well.
- Full Text:
- Date Issued: 2012
A unified data repository for rich communication services
- Authors: Sogunle, Oluwasegun Francis
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5777 , vital:20974
- Description: Rich Communication Services (RCS) is a framework that defines a set of IP-based services for the delivery of multimedia communications to mobile network subscribers. The framework unifies a set of pre-existing communication services under a single name, and permits network operators to re-use investments in existing network infrastructure, especially the IP Multimedia Subsystem (IMS), which is a core part of a mobile network and also acts as a docking station for RCS services. RCS generates and utilises disparate subscriber data sets during execution, however, it lacks a harmonised repository for the management of such data sets, thus making it difficult to obtain a unified view of heterogeneous subscriber data. This thesis proposes the creation of a unified data repository for RCS which is based on the User Data Convergence (UDC) standard. The standard was proposed by the 3rd Generation Partnership Project (3GPP), a major telecommunications standardisation group. UDC provides an approach for consolidating subscriber data into a single logical repository without adversely affecting existing network infrastructure, such as the IMS. Thus, this thesis details the design and development of a prototypical implementation of a unified repository, named Converged Subscriber Data Repository (CSDR). It adopts a polyglot persistence model for the underlying data store and exposes heterogeneous data through the Open Data Protocol (OData), which is a candidate implementation of the Ud interface defined in the UDC architecture. With the introduction of polyglot persistence, multiple data stores can be used within the CSDR and disparate network data sources can access heterogeneous data sets using OData as a standard communications protocol. As the CSDR persistence model becomes more complex due to the inclusion of more storage technologies, polyglot persistence ensures a consistent conceptual view of these data sets through OData. Importantly, the CSDR prototype was integrated into a popular open-source implementation of the core part of an IMS network known as the Open IMS Core. The successful integration of the prototype demonstrates its ability to manage and expose a consolidated view of heterogeneous subscriber data, which are generated and used by different RCS services deployed within IMS.
- Full Text:
- Date Issued: 2017
- Authors: Sogunle, Oluwasegun Francis
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5777 , vital:20974
- Description: Rich Communication Services (RCS) is a framework that defines a set of IP-based services for the delivery of multimedia communications to mobile network subscribers. The framework unifies a set of pre-existing communication services under a single name, and permits network operators to re-use investments in existing network infrastructure, especially the IP Multimedia Subsystem (IMS), which is a core part of a mobile network and also acts as a docking station for RCS services. RCS generates and utilises disparate subscriber data sets during execution, however, it lacks a harmonised repository for the management of such data sets, thus making it difficult to obtain a unified view of heterogeneous subscriber data. This thesis proposes the creation of a unified data repository for RCS which is based on the User Data Convergence (UDC) standard. The standard was proposed by the 3rd Generation Partnership Project (3GPP), a major telecommunications standardisation group. UDC provides an approach for consolidating subscriber data into a single logical repository without adversely affecting existing network infrastructure, such as the IMS. Thus, this thesis details the design and development of a prototypical implementation of a unified repository, named Converged Subscriber Data Repository (CSDR). It adopts a polyglot persistence model for the underlying data store and exposes heterogeneous data through the Open Data Protocol (OData), which is a candidate implementation of the Ud interface defined in the UDC architecture. With the introduction of polyglot persistence, multiple data stores can be used within the CSDR and disparate network data sources can access heterogeneous data sets using OData as a standard communications protocol. As the CSDR persistence model becomes more complex due to the inclusion of more storage technologies, polyglot persistence ensures a consistent conceptual view of these data sets through OData. Importantly, the CSDR prototype was integrated into a popular open-source implementation of the core part of an IMS network known as the Open IMS Core. The successful integration of the prototype demonstrates its ability to manage and expose a consolidated view of heterogeneous subscriber data, which are generated and used by different RCS services deployed within IMS.
- Full Text:
- Date Issued: 2017
An empirical, in-depth investigation into service creation in H.323 Version 4 Networks
- Authors: Penton, Jason Barry
- Date: 2003 , 2013-05-24
- Subjects: Computer programming , Computer networks , Computer network protocols
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4681 , http://hdl.handle.net/10962/d1007637 , Computer programming , Computer networks , Computer network protocols
- Description: Over the past few years there has been an increasing tendency to carry voice on IP networks as opposed to the PSTN and other switched circuit networks. Initially this trend was favoured due to reduced costs but occurred at the expense of sacrificing the quality of the voice communications. Switched circuit networks have therefore remained the preferred carrier-grade voice communication network, but this is again changing. The advancement in improved quality of service (QoS) of real-time traffic on the IP network is a contributing factor to the anticipated future of the IP network supplying carrier-grade voice communications. Another contributing factor is the possibility of creating a new range of innovative, state-of-the-art telephony and communications services that acquire leverage through the intelligence and flexibility of the IP network. The latter has yet to be fully explored. Various protocols exist that facilitate the transport of voice and other media on IP networks. The most well known and widely supported of these is H.323. This work presents and discusses H.323 version 4 service creation. The work also categorises the various H.323 services and presents the mechanisms provided by H.323 version 4 that have facilitated the development of the three services I have developed, EmailReader, Telgo323 and CANS.
- Full Text:
- Date Issued: 2003
- Authors: Penton, Jason Barry
- Date: 2003 , 2013-05-24
- Subjects: Computer programming , Computer networks , Computer network protocols
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4681 , http://hdl.handle.net/10962/d1007637 , Computer programming , Computer networks , Computer network protocols
- Description: Over the past few years there has been an increasing tendency to carry voice on IP networks as opposed to the PSTN and other switched circuit networks. Initially this trend was favoured due to reduced costs but occurred at the expense of sacrificing the quality of the voice communications. Switched circuit networks have therefore remained the preferred carrier-grade voice communication network, but this is again changing. The advancement in improved quality of service (QoS) of real-time traffic on the IP network is a contributing factor to the anticipated future of the IP network supplying carrier-grade voice communications. Another contributing factor is the possibility of creating a new range of innovative, state-of-the-art telephony and communications services that acquire leverage through the intelligence and flexibility of the IP network. The latter has yet to be fully explored. Various protocols exist that facilitate the transport of voice and other media on IP networks. The most well known and widely supported of these is H.323. This work presents and discusses H.323 version 4 service creation. The work also categorises the various H.323 services and presents the mechanisms provided by H.323 version 4 that have facilitated the development of the three services I have developed, EmailReader, Telgo323 and CANS.
- Full Text:
- Date Issued: 2003
An exploratory study of a virtual partnership for building capacity in a tertiary education institution
- Mufeti, Tulimevava Kaunapawa
- Authors: Mufeti, Tulimevava Kaunapawa
- Date: 2013-03-20
- Subjects: Internet in higher education Education, Higher -- Computer-assisted instruction Education, Higher -- Technological innovations Computer-assisted instruction -- Africa, Southern Education, Higher -- Africa, Southern Educational technology -- Africa, Southern SANTED Virtual Classroom Project
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1134 , http://hdl.handle.net/10962/d1001624
- Description: Collaborative partnerships aimed at strengthening institutional capacities are a long established trend in academia. Recent developments in Information and Communications Technologies (ICTs) have fostered a renewed interest in collaborative initiatives in the academic sphere, however, and at the same time, have created new ways of working together. Current research models do not provide sufficient methods to guide collaborations in capacity-building processes in virtual environments, especially in contexts associated with inadequate resources. Conceptual tools are therefore needed to guide the implementation of partnerships that use technology to mediate capacity building in these contexts. This research study was aimed at understanding whether and how virtual partnerships can be used to facilitate capacity building in tertiary education institutions in the SADC region. It is based on a single case study of the SANTED Virtual Classroom Project, a partnership between the Departments of Computer Science at Rhodes University (RU) and the University of Namibia (UNAM). In the project, ICTs were used to mediate the process of building teaching and research capacity in the department at UNAM. The dynamics of the partnership are explored as the implementation process developed over a period of three years. The research adopted a sociocultural perspective in the analysis of the project‟s implementation. It uses activity theory and the notion of communities of practice as conceptual frameworks to explore how the two departments organised themselves and how they harnessed the virtual environment to enable the capacity-building partnership. Activity theory provided a lens to understand the complex relationships between the different elements of the partnership activities mediated by technological tools. The concept of communities of practice, on the other hand, enabled participants‟ progress to be analysed, as they went through the various transition stages of the capacity-building process. The thesis identifies the following four categories of challenges inherent in the implementation of virtual partnerships: infrastructural, institutional, cultural and individual expectations. It also emphasises the need for identifying the different transition stages corresponding to the levels of participation in the capacity-building process. The thesis recommends that the implementation of virtual partnerships for capacity building purposes in the SADC region must focus on: identifying the appropriate capacity building strategies at Abstract ii each transition stage; finding appropriate, light-weight virtual classroom solutions; identifying appropriate pedagogic models to suit available technology; addressing systemic tensions that can arise as a result of different institutional cultures; and developing and nurturing virtual communities of practice to ensure sustainability. The research findings contribute to the body of knowledge exploring the use of technologies to develop and strengthen human resource capacities in developing contexts in a sustainable way. More importantly, it contributes to the literature on collaborative virtual partnerships in the SADC region, and demonstrates one way in which the operations of such a partnership may be supported in similar contexts , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Authors: Mufeti, Tulimevava Kaunapawa
- Date: 2013-03-20
- Subjects: Internet in higher education Education, Higher -- Computer-assisted instruction Education, Higher -- Technological innovations Computer-assisted instruction -- Africa, Southern Education, Higher -- Africa, Southern Educational technology -- Africa, Southern SANTED Virtual Classroom Project
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1134 , http://hdl.handle.net/10962/d1001624
- Description: Collaborative partnerships aimed at strengthening institutional capacities are a long established trend in academia. Recent developments in Information and Communications Technologies (ICTs) have fostered a renewed interest in collaborative initiatives in the academic sphere, however, and at the same time, have created new ways of working together. Current research models do not provide sufficient methods to guide collaborations in capacity-building processes in virtual environments, especially in contexts associated with inadequate resources. Conceptual tools are therefore needed to guide the implementation of partnerships that use technology to mediate capacity building in these contexts. This research study was aimed at understanding whether and how virtual partnerships can be used to facilitate capacity building in tertiary education institutions in the SADC region. It is based on a single case study of the SANTED Virtual Classroom Project, a partnership between the Departments of Computer Science at Rhodes University (RU) and the University of Namibia (UNAM). In the project, ICTs were used to mediate the process of building teaching and research capacity in the department at UNAM. The dynamics of the partnership are explored as the implementation process developed over a period of three years. The research adopted a sociocultural perspective in the analysis of the project‟s implementation. It uses activity theory and the notion of communities of practice as conceptual frameworks to explore how the two departments organised themselves and how they harnessed the virtual environment to enable the capacity-building partnership. Activity theory provided a lens to understand the complex relationships between the different elements of the partnership activities mediated by technological tools. The concept of communities of practice, on the other hand, enabled participants‟ progress to be analysed, as they went through the various transition stages of the capacity-building process. The thesis identifies the following four categories of challenges inherent in the implementation of virtual partnerships: infrastructural, institutional, cultural and individual expectations. It also emphasises the need for identifying the different transition stages corresponding to the levels of participation in the capacity-building process. The thesis recommends that the implementation of virtual partnerships for capacity building purposes in the SADC region must focus on: identifying the appropriate capacity building strategies at Abstract ii each transition stage; finding appropriate, light-weight virtual classroom solutions; identifying appropriate pedagogic models to suit available technology; addressing systemic tensions that can arise as a result of different institutional cultures; and developing and nurturing virtual communities of practice to ensure sustainability. The research findings contribute to the body of knowledge exploring the use of technologies to develop and strengthen human resource capacities in developing contexts in a sustainable way. More importantly, it contributes to the literature on collaborative virtual partnerships in the SADC region, and demonstrates one way in which the operations of such a partnership may be supported in similar contexts , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
An investigation into the readiness of open source software to build a Telco Cloud for virtualising network functions
- Authors: Chindeka, Tapiwa C
- Date: 2020
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/124320 , vital:35593
- Description: Cloud computing offers new mechanisms that change the way networks can be created and managed. The increased demand for multimedia and Internet of Things (IoT) services using the Internet Protocol is also fueling the need to look more into a networking approach that is less reliant on physical hardware components and allows new networks and network components to be created on-demand. Network Function Virtualisation (NFV) is a networking paradigm that decouples network functions from the hardware on which they run on. This offers new approaches to telecommunication providers who are looking to new ways of improving Quality of Service (QoS) in cost effective ways. Cloud technologies have given way to more specialised cloud environments such as the telco cloud. The telco cloud is a cloud environment where telecommunication services are hosted utilising NFV techniques. As the use of telecommunication standards moves towards 5G, network services will be provided in a virtualised manner in order to keep up with the demand. Open source software is a driver for innovation as it is has a collaborative culture to support it. This research investigates the readiness of open source tools to build a telco cloud that supports functions such as autoscaling and fault tolerance. Currently available open source software was explored for the different aspects involved in building a cloud from the ground up. The ETSI NFV MANO framework is also discussed as it is a widely used guiding standard for implementing NFV. Guided by the ETSI NFV MANO framework, open source software was used in an experiment to build a resilient cloud environment in which a virtualised IP Multimedia Subsystem (vIMS) network was deployed. Through this experimentation, it is evident that open source tools are mature enough to build the cloud environment and its ETSI NFV MANO compliant orchestration. However, features such as autoscaling and fault tolerance are still fairly immature and experimental.
- Full Text:
- Date Issued: 2020
- Authors: Chindeka, Tapiwa C
- Date: 2020
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/124320 , vital:35593
- Description: Cloud computing offers new mechanisms that change the way networks can be created and managed. The increased demand for multimedia and Internet of Things (IoT) services using the Internet Protocol is also fueling the need to look more into a networking approach that is less reliant on physical hardware components and allows new networks and network components to be created on-demand. Network Function Virtualisation (NFV) is a networking paradigm that decouples network functions from the hardware on which they run on. This offers new approaches to telecommunication providers who are looking to new ways of improving Quality of Service (QoS) in cost effective ways. Cloud technologies have given way to more specialised cloud environments such as the telco cloud. The telco cloud is a cloud environment where telecommunication services are hosted utilising NFV techniques. As the use of telecommunication standards moves towards 5G, network services will be provided in a virtualised manner in order to keep up with the demand. Open source software is a driver for innovation as it is has a collaborative culture to support it. This research investigates the readiness of open source tools to build a telco cloud that supports functions such as autoscaling and fault tolerance. Currently available open source software was explored for the different aspects involved in building a cloud from the ground up. The ETSI NFV MANO framework is also discussed as it is a widely used guiding standard for implementing NFV. Guided by the ETSI NFV MANO framework, open source software was used in an experiment to build a resilient cloud environment in which a virtualised IP Multimedia Subsystem (vIMS) network was deployed. Through this experimentation, it is evident that open source tools are mature enough to build the cloud environment and its ETSI NFV MANO compliant orchestration. However, features such as autoscaling and fault tolerance are still fairly immature and experimental.
- Full Text:
- Date Issued: 2020
Building an E-health system for health awareness campaigns in poor areas
- Authors: Gremu, Chikumbutso David
- Date: 2015
- Subjects: National health services -- South Africa , Medical informatics , Public health -- Information services
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4708 , http://hdl.handle.net/10962/d1017930
- Description: Appropriate e-services as well as revenue generation capabilities are key to the deployment and the sustainability for ICT installations in poor areas, particularly common in developing country. The area of e-Health is a promising area for e-services that are both important to the population in those areas and potentially of direct interest to National Health Organizations, which already spend money for Health campaigns there. This thesis focuses on the design, implementation, and full functional testing of HealthAware, an application that allows health organization to set up targeted awareness campaigns for poor areas. Requirements for such application are very specific, starting from the fact that the preparation of the campaign and its execution/consumption happen in two different environments from a technological and social point of view. Part of the research work done for this thesis was to make the above requirements explicit and then use them in the design. This phase of the research was facilitated by the fact that the thesis' work was executed within the context of the Siyakhula Living Lab (SLL; www.siyakhulaLL.org), which has accumulated multi-year experience of ICT deployment in such areas. As a result of the found requirements, HealthAware comprises two components, which are web-based, Java applications that run in a peer-to-peer fashion. The first component, the Dashboard, is used to create, manage, and publish information for conducting awareness campaigns or surveys. The second component, HealthMessenger, facilitates users' access to the campaigns or surveys that were created using the Dashboard. The HealthMessenger was designed to be hosted on TeleWeaver while the Dashboard is hosted independently of TeleWeaver and simply communicates with the HealthMessenger through webservices. TeleWeaver is an application integration platform developed within the SLL to host software applications for poor areas. Using a core service of TeleWeaver, the profile service, where all the users' defining elements are contained, campaigns and surveys can be easily and effectively targeted, for example to match specific demographics or geographic locations. Revenue generation is attained via the logging of the interactions of the target users in the communities with the applications in TeleWeaver, from which billing data is generated according to the specific contractual agreements with the National Health Organization. From a general point of view, HealthAware contributes to the concrete realizations of a bidirectional access channel between Health Organizations and users in poor communities, which not only allows the communication of appropriate content in both directions, but get 'monetized' and in so doing becomes a revenue generator.
- Full Text:
- Date Issued: 2015
- Authors: Gremu, Chikumbutso David
- Date: 2015
- Subjects: National health services -- South Africa , Medical informatics , Public health -- Information services
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4708 , http://hdl.handle.net/10962/d1017930
- Description: Appropriate e-services as well as revenue generation capabilities are key to the deployment and the sustainability for ICT installations in poor areas, particularly common in developing country. The area of e-Health is a promising area for e-services that are both important to the population in those areas and potentially of direct interest to National Health Organizations, which already spend money for Health campaigns there. This thesis focuses on the design, implementation, and full functional testing of HealthAware, an application that allows health organization to set up targeted awareness campaigns for poor areas. Requirements for such application are very specific, starting from the fact that the preparation of the campaign and its execution/consumption happen in two different environments from a technological and social point of view. Part of the research work done for this thesis was to make the above requirements explicit and then use them in the design. This phase of the research was facilitated by the fact that the thesis' work was executed within the context of the Siyakhula Living Lab (SLL; www.siyakhulaLL.org), which has accumulated multi-year experience of ICT deployment in such areas. As a result of the found requirements, HealthAware comprises two components, which are web-based, Java applications that run in a peer-to-peer fashion. The first component, the Dashboard, is used to create, manage, and publish information for conducting awareness campaigns or surveys. The second component, HealthMessenger, facilitates users' access to the campaigns or surveys that were created using the Dashboard. The HealthMessenger was designed to be hosted on TeleWeaver while the Dashboard is hosted independently of TeleWeaver and simply communicates with the HealthMessenger through webservices. TeleWeaver is an application integration platform developed within the SLL to host software applications for poor areas. Using a core service of TeleWeaver, the profile service, where all the users' defining elements are contained, campaigns and surveys can be easily and effectively targeted, for example to match specific demographics or geographic locations. Revenue generation is attained via the logging of the interactions of the target users in the communities with the applications in TeleWeaver, from which billing data is generated according to the specific contractual agreements with the National Health Organization. From a general point of view, HealthAware contributes to the concrete realizations of a bidirectional access channel between Health Organizations and users in poor communities, which not only allows the communication of appropriate content in both directions, but get 'monetized' and in so doing becomes a revenue generator.
- Full Text:
- Date Issued: 2015
Building IKhwezi, a digital platform to capture everyday Indigenous Knowledge for improving educational outcomes in marginalised communities
- Authors: Ntšekhe, Mathe V K
- Date: 2018
- Subjects: Information technology , Knowledge management , Traditional ecological knowledge , Pedagogical content knowledge , Traditional ecological knowledge -- Technological innovations , IKhwezi , ICT4D , Indigenous Technological Pedagogical Content Knowledge (I-TPACK) , Siyakhula Living Lab
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62505 , vital:28200
- Description: Aptly captured in the name, the broad mandate of Information and Communications Technologies for Development (ICT4D) is to facilitate the use of Information and Communication Technologies (ICTs) in society to support development. Education, as often stated, is the cornerstone for development, imparting knowledge for conceiving and realising development. In this thesis, we explore how everyday Indigenous Knowledge (IK) can be collected digitally, to enhance the educational outcomes of learners from marginalised backgrounds, by stimulating the production of teaching and learning materials that include the local imagery to have resonance with the learners. As part of the exploration, we reviewed a framework known as Technological Pedagogical Content Knowledge (TPACK), which spells out the different kinds of knowledge needed by teachers to teach effectively with ICTs. In this framework, IK is not present explicitly, but through the concept of context(s). Using Afrocentric and Pan-African scholarship, we argue that this logic is linked to colonialism and a critical decolonising pedagogy necessarily demands explication of IK: to make visible the cultures of the learners in the margins (e.g. Black rural learners). On the strength of this argument, we have proposed that TPACK be augumented to become Indigenous Technological Pedagogical Content Knowledge (I-TPACK). Through this augumentation, I-TPACK becomes an Afrocentric framework for a multicultural education in the digital era. The design of the digital platform for capturing IK relevant for formal education, was done in the Siyakhula Living Lab (SLL). The core idea of a Living Lab (LL) is that users must be understood in the context of their lived everyday reality. Further, they must be involved as co-creators in the design and innovation processes. On a methodological level, the LL environment allowed for the fusing together of multiple methods that can help to create a fitting solution. In this thesis, we followed an iterative user-centred methodology rooted in ethnography and phenomenology. Specifically, through long term conversations and interaction with teachers and ethnographic observations, we conceptualized a platform, IKhwezi, that facilitates the collection of context-sensitive content, collaboratively, and with cost and convenience in mind. We implemented this platform using MediaWiki, based on a number of considerations. From the ICT4D disciplinary point of view, a major consideration was being open to the possibility that other forms of innovation—and, not just ‘technovelty’ (i.e. technological/- technical innovation)—can provide a breakthrough or ingenious solution to the problem at hand. In a sense, we were reinforcing the growing sentiment within the discipline that technology is not the goal, but the means to foregrounding the commonality of the human experience in working towards development. Testing confirmed that there is some value in the platform. This is despite the challenges to onboard users, in pursuit of more content that could bolster the value of everyday IK in improving the educational outcomes of all learners.
- Full Text:
- Date Issued: 2018
- Authors: Ntšekhe, Mathe V K
- Date: 2018
- Subjects: Information technology , Knowledge management , Traditional ecological knowledge , Pedagogical content knowledge , Traditional ecological knowledge -- Technological innovations , IKhwezi , ICT4D , Indigenous Technological Pedagogical Content Knowledge (I-TPACK) , Siyakhula Living Lab
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62505 , vital:28200
- Description: Aptly captured in the name, the broad mandate of Information and Communications Technologies for Development (ICT4D) is to facilitate the use of Information and Communication Technologies (ICTs) in society to support development. Education, as often stated, is the cornerstone for development, imparting knowledge for conceiving and realising development. In this thesis, we explore how everyday Indigenous Knowledge (IK) can be collected digitally, to enhance the educational outcomes of learners from marginalised backgrounds, by stimulating the production of teaching and learning materials that include the local imagery to have resonance with the learners. As part of the exploration, we reviewed a framework known as Technological Pedagogical Content Knowledge (TPACK), which spells out the different kinds of knowledge needed by teachers to teach effectively with ICTs. In this framework, IK is not present explicitly, but through the concept of context(s). Using Afrocentric and Pan-African scholarship, we argue that this logic is linked to colonialism and a critical decolonising pedagogy necessarily demands explication of IK: to make visible the cultures of the learners in the margins (e.g. Black rural learners). On the strength of this argument, we have proposed that TPACK be augumented to become Indigenous Technological Pedagogical Content Knowledge (I-TPACK). Through this augumentation, I-TPACK becomes an Afrocentric framework for a multicultural education in the digital era. The design of the digital platform for capturing IK relevant for formal education, was done in the Siyakhula Living Lab (SLL). The core idea of a Living Lab (LL) is that users must be understood in the context of their lived everyday reality. Further, they must be involved as co-creators in the design and innovation processes. On a methodological level, the LL environment allowed for the fusing together of multiple methods that can help to create a fitting solution. In this thesis, we followed an iterative user-centred methodology rooted in ethnography and phenomenology. Specifically, through long term conversations and interaction with teachers and ethnographic observations, we conceptualized a platform, IKhwezi, that facilitates the collection of context-sensitive content, collaboratively, and with cost and convenience in mind. We implemented this platform using MediaWiki, based on a number of considerations. From the ICT4D disciplinary point of view, a major consideration was being open to the possibility that other forms of innovation—and, not just ‘technovelty’ (i.e. technological/- technical innovation)—can provide a breakthrough or ingenious solution to the problem at hand. In a sense, we were reinforcing the growing sentiment within the discipline that technology is not the goal, but the means to foregrounding the commonality of the human experience in working towards development. Testing confirmed that there is some value in the platform. This is despite the challenges to onboard users, in pursuit of more content that could bolster the value of everyday IK in improving the educational outcomes of all learners.
- Full Text:
- Date Issued: 2018
Building the field component of a smart irrigation system: A detailed experience of a computer science graduate
- Authors: Pipile, Yamnkelani Yonela
- Date: 2021-10
- Subjects: Irrigation efficiency Computer-aided design South Africa , Irrigation projects Computer-aided design South Africa , Internet of things , Machine-to-machine communications , Smart water grids South Africa , Raspberry Pi (Computer) , Arduino (Programmable controller) , ZigBee , MQTT (MQ Telemetry Transport) , MQTT-SN , XBee
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/191814 , vital:45167
- Description: South Africa is a semi-arid area with an average annual rainfall of approximately 450mm, 60 per cent of which goes towards irrigation. Current irrigation systems generally apply water in a uniform manner across a field, which is both inefficient and can kill the plants. The Internet of Things (IoT), an emerging technology involving the utilization of sensors and actuators to build complex feedback systems, present an opportunity to build a smart irrigation solution. This research project illustrates the development of the field components of a water monitoring system using off the shelf and inexpensive components, exploring at the same time how easy or difficult it would be for a general Computer Science graduate to use hardware components and associated tools within the IoT area. The problem was initially broken down through a classical top-down process, in order to identify the components such as micro-computers, micro- controllers, sensors and network connections, that would be needed to build the solution. I then selected the Raspberry Pi 3, the Arduino Arduino Uno, the MH-Sensor-Series hygrometer, the MQTT messaging protocol, and the ZigBee communication protocol as implemented in the XBee S2C. Once the components were identified, the work followed a bottom-up approach: I studied the components in isolation and relative to each other, through a structured series of experiments, with each experiment addressing a specific component and examining how easy was to use the component. While each experiment allowed the author to acquire and deepen her understanding of each component, and progressively built a more sophisticated prototype, towards the complete solution. I found the vast majority of the identified components and tools to be easy to use, well documented, and most importantly, mature for consumption by our target user, until I encountered the MQTT-SN (MQTT-Sensor Network) implementation, not as mature as the rest. This resulted in us designing and implementing a light-weight, general ZigBee/MQTT gateway, named “yoGa” (Yonella's Gateway) from the author. At the end of the research, I was able to build the field components of a smart irrigation system using the selected tools, including the yoGa gateway, proving practically that a Computer Science graduate from a South African University can become productive in the emerging IoT area. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
- Full Text:
- Date Issued: 2021-10
- Authors: Pipile, Yamnkelani Yonela
- Date: 2021-10
- Subjects: Irrigation efficiency Computer-aided design South Africa , Irrigation projects Computer-aided design South Africa , Internet of things , Machine-to-machine communications , Smart water grids South Africa , Raspberry Pi (Computer) , Arduino (Programmable controller) , ZigBee , MQTT (MQ Telemetry Transport) , MQTT-SN , XBee
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/191814 , vital:45167
- Description: South Africa is a semi-arid area with an average annual rainfall of approximately 450mm, 60 per cent of which goes towards irrigation. Current irrigation systems generally apply water in a uniform manner across a field, which is both inefficient and can kill the plants. The Internet of Things (IoT), an emerging technology involving the utilization of sensors and actuators to build complex feedback systems, present an opportunity to build a smart irrigation solution. This research project illustrates the development of the field components of a water monitoring system using off the shelf and inexpensive components, exploring at the same time how easy or difficult it would be for a general Computer Science graduate to use hardware components and associated tools within the IoT area. The problem was initially broken down through a classical top-down process, in order to identify the components such as micro-computers, micro- controllers, sensors and network connections, that would be needed to build the solution. I then selected the Raspberry Pi 3, the Arduino Arduino Uno, the MH-Sensor-Series hygrometer, the MQTT messaging protocol, and the ZigBee communication protocol as implemented in the XBee S2C. Once the components were identified, the work followed a bottom-up approach: I studied the components in isolation and relative to each other, through a structured series of experiments, with each experiment addressing a specific component and examining how easy was to use the component. While each experiment allowed the author to acquire and deepen her understanding of each component, and progressively built a more sophisticated prototype, towards the complete solution. I found the vast majority of the identified components and tools to be easy to use, well documented, and most importantly, mature for consumption by our target user, until I encountered the MQTT-SN (MQTT-Sensor Network) implementation, not as mature as the rest. This resulted in us designing and implementing a light-weight, general ZigBee/MQTT gateway, named “yoGa” (Yonella's Gateway) from the author. At the end of the research, I was able to build the field components of a smart irrigation system using the selected tools, including the yoGa gateway, proving practically that a Computer Science graduate from a South African University can become productive in the emerging IoT area. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
- Full Text:
- Date Issued: 2021-10
COIN : a customisable, incentive driven video on demand framework for low-cost IPTV services
- Authors: Musvibe, Ray
- Date: 2012 , 2012-03-02
- Subjects: Internet television , Digital television , Television broadcasting -- Technological innovations , Multicasting (Computer networks) , Video dial tone , Open source software , Telecommunication , Capital investments
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4654 , http://hdl.handle.net/10962/d1006650 , Internet television , Digital television , Television broadcasting -- Technological innovations , Multicasting (Computer networks) , Video dial tone , Open source software , Telecommunication , Capital investments
- Description: There has been a significant rise in the provision of television and video services over IP (IPTV) in recent years. Increasing network capacity and falling bandwidth costs have made it both technically and economically feasible for service providers to deliver IPTV services. Several telecommunications (telco) operators worldwide are rolling out IPTV solutions and view IPTV as a major service differentiator and alternative revenue source. The main challenge that IPTV providers currently face, however, is the increasingly congested television service provider market, which also includes Internet Television. IPTV solutions therefore need strong service differentiators to succeed. IPTV solutions can doubtlessly sell much faster if they are more affordable or low-cost. Advertising has already been used in many service sectors to help lower service costs, including traditional broadcast television. This thesis therefore explores the role that advertising can play in helping to lower the cost of IPTV services and to incentivise IPTV billing. Another approach that IPTV providers can use to help sell their product is by addressing the growing need for control by today's multimedia users. This thesis will therefore explore the varied approaches that can be used to achieve viewer focused IPTV implementations. To further lower the cost of IPTV services, telcos can also turn to low-cost, open source platforms for service delivery. The adoption of low-cost infrastructure by telcos can lead to reduced Capital Expenditure (CAPEX), which in turn can lead to lower service fees, and ultimately to higher subscriptions and revenue. Therefore, in this thesis, the author proposes a CustOmisable, INcentive (COIN) driven Video on Demand (VoD) framework to be developed and deployed using the Mobicents Communication Platform, an open source service creation and execution platform. The COIN framework aims to provide a viewer focused, economically competitive service that combines the potential cost savings of using free and open source software (FOSS), with an innovative, incentive-driven billing approach. This project will also aim to evaluate whether the Mobicents Platform is a suitable service creation and execution platform for the proposed framework. Additionally, the proposed implementation aims to be interoperable with other IPTV implementations, hence shall follow current IPTV standardisation architectures and trends. The service testbed and its implementation are described in detail and only free and open source software is used; this is to enable its easy duplication and extension for future research. , TeX output 2012.03.02:1241 , Adobe Acrobat 9.2 Paper Capture Plug-in
- Full Text:
- Date Issued: 2012
- Authors: Musvibe, Ray
- Date: 2012 , 2012-03-02
- Subjects: Internet television , Digital television , Television broadcasting -- Technological innovations , Multicasting (Computer networks) , Video dial tone , Open source software , Telecommunication , Capital investments
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4654 , http://hdl.handle.net/10962/d1006650 , Internet television , Digital television , Television broadcasting -- Technological innovations , Multicasting (Computer networks) , Video dial tone , Open source software , Telecommunication , Capital investments
- Description: There has been a significant rise in the provision of television and video services over IP (IPTV) in recent years. Increasing network capacity and falling bandwidth costs have made it both technically and economically feasible for service providers to deliver IPTV services. Several telecommunications (telco) operators worldwide are rolling out IPTV solutions and view IPTV as a major service differentiator and alternative revenue source. The main challenge that IPTV providers currently face, however, is the increasingly congested television service provider market, which also includes Internet Television. IPTV solutions therefore need strong service differentiators to succeed. IPTV solutions can doubtlessly sell much faster if they are more affordable or low-cost. Advertising has already been used in many service sectors to help lower service costs, including traditional broadcast television. This thesis therefore explores the role that advertising can play in helping to lower the cost of IPTV services and to incentivise IPTV billing. Another approach that IPTV providers can use to help sell their product is by addressing the growing need for control by today's multimedia users. This thesis will therefore explore the varied approaches that can be used to achieve viewer focused IPTV implementations. To further lower the cost of IPTV services, telcos can also turn to low-cost, open source platforms for service delivery. The adoption of low-cost infrastructure by telcos can lead to reduced Capital Expenditure (CAPEX), which in turn can lead to lower service fees, and ultimately to higher subscriptions and revenue. Therefore, in this thesis, the author proposes a CustOmisable, INcentive (COIN) driven Video on Demand (VoD) framework to be developed and deployed using the Mobicents Communication Platform, an open source service creation and execution platform. The COIN framework aims to provide a viewer focused, economically competitive service that combines the potential cost savings of using free and open source software (FOSS), with an innovative, incentive-driven billing approach. This project will also aim to evaluate whether the Mobicents Platform is a suitable service creation and execution platform for the proposed framework. Additionally, the proposed implementation aims to be interoperable with other IPTV implementations, hence shall follow current IPTV standardisation architectures and trends. The service testbed and its implementation are described in detail and only free and open source software is used; this is to enable its easy duplication and extension for future research. , TeX output 2012.03.02:1241 , Adobe Acrobat 9.2 Paper Capture Plug-in
- Full Text:
- Date Issued: 2012
Culturally-relevant augmented user interfaces for illiterate and semi-literate users
- Authors: Gavaza, Takayedzwa
- Date: 2012 , 2012-06-14
- Subjects: User interfaces (Computer systems) -- Research , Computer software -- Research , Graphical user interfaces (Computer systems) -- Research , Human-computer interaction , Computers and literacy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4665 , http://hdl.handle.net/10962/d1006679 , User interfaces (Computer systems) -- Research , Computer software -- Research , Graphical user interfaces (Computer systems) -- Research , Human-computer interaction , Computers and literacy
- Description: This thesis discusses guidelines for developers of Augmented User Interfaces that can be used by illiterate and semi-literate users. To discover how illiterate and semi-literate users intuitively understand interaction with a computer, a series of Wizard of Oz experiments were conducted. In the first Wizard of Oz study, users were presented with a standard desktop computer, fitted with a number of input devices to determine how they assume interaction should occur. This study found that the users preferred the use of speech and gestures which mirrored findings from other researchers. The study also found that users struggled to understand the tab metaphor which is used frequently in applications. From these findings, a localised culturally-relevant tab interface was developed to determine the feasibility of localised Graphical User Interface components. A second study was undertaken to compare the localised tab interface with the traditional tabbed interface. This study collected both quantitative and qualitative data from the participants. It found that users could interact with a localised tabbed interface faster and more accurately than with the traditional counterparts. More importantly, users stated that they intuitively understood the localised interface component, whereas they did not understand the traditional tab metaphor. These user studies have shown that the use of self-explanatory animations, video feedback, localised tabbed interface metaphors and voice output have a positive impact on enabling illiterate and semi-literate users to access information. , TeX , Adobe Acrobat 9.51 Paper Capture Plug-in
- Full Text:
- Date Issued: 2012
- Authors: Gavaza, Takayedzwa
- Date: 2012 , 2012-06-14
- Subjects: User interfaces (Computer systems) -- Research , Computer software -- Research , Graphical user interfaces (Computer systems) -- Research , Human-computer interaction , Computers and literacy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4665 , http://hdl.handle.net/10962/d1006679 , User interfaces (Computer systems) -- Research , Computer software -- Research , Graphical user interfaces (Computer systems) -- Research , Human-computer interaction , Computers and literacy
- Description: This thesis discusses guidelines for developers of Augmented User Interfaces that can be used by illiterate and semi-literate users. To discover how illiterate and semi-literate users intuitively understand interaction with a computer, a series of Wizard of Oz experiments were conducted. In the first Wizard of Oz study, users were presented with a standard desktop computer, fitted with a number of input devices to determine how they assume interaction should occur. This study found that the users preferred the use of speech and gestures which mirrored findings from other researchers. The study also found that users struggled to understand the tab metaphor which is used frequently in applications. From these findings, a localised culturally-relevant tab interface was developed to determine the feasibility of localised Graphical User Interface components. A second study was undertaken to compare the localised tab interface with the traditional tabbed interface. This study collected both quantitative and qualitative data from the participants. It found that users could interact with a localised tabbed interface faster and more accurately than with the traditional counterparts. More importantly, users stated that they intuitively understood the localised interface component, whereas they did not understand the traditional tab metaphor. These user studies have shown that the use of self-explanatory animations, video feedback, localised tabbed interface metaphors and voice output have a positive impact on enabling illiterate and semi-literate users to access information. , TeX , Adobe Acrobat 9.51 Paper Capture Plug-in
- Full Text:
- Date Issued: 2012
Decorating Asterisk : experiments in service creation for a multi-protocol telephony environment using open source tools
- Authors: Hitchcock, Jonathan
- Date: 2006
- Subjects: Asterisk (Computer file) , Internet telephony
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4635 , http://hdl.handle.net/10962/d1006539 , Asterisk (Computer file) , Internet telephony
- Description: As Voice over IP becomes more prevalent, value-adds to the service will become ubiquitous. Voice over IP (VoIP) is no longer a single service application, but an array of marketable services of increasing depth, which are moving into the non-desktop market. In addition, as the range of devices being generally used increases, it will become necessary for all services, including VoIP services, to be accessible from multiple platforms and through varied interfaces. With the recent introduction and growth of the open source software PBX system named Asterisk, the possibility of achieving these goals has become more concrete. In addition to Asterisk, a number of open source systems are being developed which facilitate the development of systems that interoperate over a wide variety of platforms and through multiple interfaces. This thesis investigates Asterisk in terms of its viability to provide the depth of services that will be required in a VoIP environment, as well as a number of other open source systems in terms of what they can offer such a system. In addition, it investigates whether these services can be made available on different devices. Using various systems built as a proof-of-concept, this thesis shows that Asterisk, in conjunction with various other open source projects, such as the Twisted framework provides a concrete tool which can be used to realise flexible and protocol independent telephony solutions for a small to medium enterprise.
- Full Text:
- Date Issued: 2006
- Authors: Hitchcock, Jonathan
- Date: 2006
- Subjects: Asterisk (Computer file) , Internet telephony
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4635 , http://hdl.handle.net/10962/d1006539 , Asterisk (Computer file) , Internet telephony
- Description: As Voice over IP becomes more prevalent, value-adds to the service will become ubiquitous. Voice over IP (VoIP) is no longer a single service application, but an array of marketable services of increasing depth, which are moving into the non-desktop market. In addition, as the range of devices being generally used increases, it will become necessary for all services, including VoIP services, to be accessible from multiple platforms and through varied interfaces. With the recent introduction and growth of the open source software PBX system named Asterisk, the possibility of achieving these goals has become more concrete. In addition to Asterisk, a number of open source systems are being developed which facilitate the development of systems that interoperate over a wide variety of platforms and through multiple interfaces. This thesis investigates Asterisk in terms of its viability to provide the depth of services that will be required in a VoIP environment, as well as a number of other open source systems in terms of what they can offer such a system. In addition, it investigates whether these services can be made available on different devices. Using various systems built as a proof-of-concept, this thesis shows that Asterisk, in conjunction with various other open source projects, such as the Twisted framework provides a concrete tool which can be used to realise flexible and protocol independent telephony solutions for a small to medium enterprise.
- Full Text:
- Date Issued: 2006
Design of a performance evaluation tool for multimedia databases with special reference to Oracle
- Authors: Stakemire, Tonia
- Date: 2004
- Subjects: Oracle (Computer file) , Application software -- Evaluation , Database management -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4705 , http://hdl.handle.net/10962/d1015975
- Description: Increased production and use of multimedia data has led to the development of a more advanced Database Management System (DBMS), like an Object Relational Database Management System (ORDBMS). These advanced databases are necessitated by the complexity in structure and the functionality required by multimedia data. Unfortunately, no suitable benchmarks exist with which to test the performance of databases when handling multimedia data. This thesis describes the design of a benchmark to measure the performance of basic functionality found in multimedia databases. The benchmark, called MORD (Multimedia Object Relational Databases), targets Oracle, a well known commercial Object Relational Database Management System (ORDBMS) that can handle multimedia data. Although MORD targets Oracle, it can easily be applied to other Multimedia Database Management System (MMDBMS) as a result of a design that stressed its portability, and simplicity. MORD consists of a database schema, test data, and code to simulate representative queries on multimedia databases. A number of experiments are described that validate MORD and ensure its correct design and that its objectives are met. A by-product of these experiments is an initial understanding of the performance of multimedia databases. The experiments show that with multimedia data the buffer cache should be at least large enough to hold the largest dataset, a bigger block size improves the performance, and turning off logging and caching for bulk loading improves the performance. MORD can be used to compare different ORDBMS or to assist in the configuration of a specific database.
- Full Text:
- Date Issued: 2004
- Authors: Stakemire, Tonia
- Date: 2004
- Subjects: Oracle (Computer file) , Application software -- Evaluation , Database management -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4705 , http://hdl.handle.net/10962/d1015975
- Description: Increased production and use of multimedia data has led to the development of a more advanced Database Management System (DBMS), like an Object Relational Database Management System (ORDBMS). These advanced databases are necessitated by the complexity in structure and the functionality required by multimedia data. Unfortunately, no suitable benchmarks exist with which to test the performance of databases when handling multimedia data. This thesis describes the design of a benchmark to measure the performance of basic functionality found in multimedia databases. The benchmark, called MORD (Multimedia Object Relational Databases), targets Oracle, a well known commercial Object Relational Database Management System (ORDBMS) that can handle multimedia data. Although MORD targets Oracle, it can easily be applied to other Multimedia Database Management System (MMDBMS) as a result of a design that stressed its portability, and simplicity. MORD consists of a database schema, test data, and code to simulate representative queries on multimedia databases. A number of experiments are described that validate MORD and ensure its correct design and that its objectives are met. A by-product of these experiments is an initial understanding of the performance of multimedia databases. The experiments show that with multimedia data the buffer cache should be at least large enough to hold the largest dataset, a bigger block size improves the performance, and turning off logging and caching for bulk loading improves the performance. MORD can be used to compare different ORDBMS or to assist in the configuration of a specific database.
- Full Text:
- Date Issued: 2004
Designing and prototyping WebRTC and IMS integration using open source tools
- Authors: Motsumi, Tebagano Valerie
- Date: 2018
- Subjects: Internet Protocol multimedia subsystem , Session Initiation Protocol (Computer network protocol) , Computer software -- Development , Web Real-time Communications (WebRTC)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63245 , vital:28386
- Description: WebRTC, or Web Real-time Communications, is a collection of web standards that detail the mechanisms, architectures and protocols that work together to deliver real-time multimedia services to the web browser. It represents a significant shift from the historical approach of using browser plugins, which over time, have proven cumbersome and problematic. Furthermore, it adopts various Internet standards in areas such as identity management, peer-to-peer connectivity, data exchange and media encoding, to provide a system that is truly open and interoperable. Given that WebRTC enables the delivery of multimedia content to any Internet Protocol (IP)-enabled device capable of hosting a web browser, this technology could potentially be used and deployed over millions of smartphones, tablets and personal computers worldwide. This service and device convergence remains an important goal of telecommunication network operators who seek to enable it through a converged network that is based on the IP Multimedia Subsystem (IMS). IMS is an IP-based subsystem that sits at the core of a modern telecommunication network and acts as the main routing substrate for media services and applications such as those that WebRTC realises. The combination of WebRTC and IMS represents an attractive coupling, and as such, a protracted investigation could help to answer important questions around the technical challenges that are involved in their integration, and the merits of various design alternatives that present themselves. This thesis is the result of such an investigation and culminates in the presentation of a detailed architectural model that is validated with a prototypical implementation in an open source testbed. The model is built on six requirements which emerge from an analysis of the literature, including previous interventions in IMS networks and a key technical report on design alternatives. Furthermore, this thesis argues that the client architecture requires support for web-oriented signalling, identity and call handling techniques leading to a potential for IMS networks to natively support these techniques as operator networks continue to grow and develop. The proposed model advocates the use of SIP over WebSockets for signalling and DTLS-SRTP for media to enable one-to-one communication and can be extended through additional functions resulting in a modular architecture. The model was implemented using open source tools which were assembled to create an experimental network testbed, and tests were conducted demonstrating successful cross domain communications under various conditions. The thesis has a strong focus on enabling ordinary software developers to assemble a prototypical network such as the one that was assembled and aims to enable experimentation in application use cases for integrated environments.
- Full Text:
- Date Issued: 2018
- Authors: Motsumi, Tebagano Valerie
- Date: 2018
- Subjects: Internet Protocol multimedia subsystem , Session Initiation Protocol (Computer network protocol) , Computer software -- Development , Web Real-time Communications (WebRTC)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63245 , vital:28386
- Description: WebRTC, or Web Real-time Communications, is a collection of web standards that detail the mechanisms, architectures and protocols that work together to deliver real-time multimedia services to the web browser. It represents a significant shift from the historical approach of using browser plugins, which over time, have proven cumbersome and problematic. Furthermore, it adopts various Internet standards in areas such as identity management, peer-to-peer connectivity, data exchange and media encoding, to provide a system that is truly open and interoperable. Given that WebRTC enables the delivery of multimedia content to any Internet Protocol (IP)-enabled device capable of hosting a web browser, this technology could potentially be used and deployed over millions of smartphones, tablets and personal computers worldwide. This service and device convergence remains an important goal of telecommunication network operators who seek to enable it through a converged network that is based on the IP Multimedia Subsystem (IMS). IMS is an IP-based subsystem that sits at the core of a modern telecommunication network and acts as the main routing substrate for media services and applications such as those that WebRTC realises. The combination of WebRTC and IMS represents an attractive coupling, and as such, a protracted investigation could help to answer important questions around the technical challenges that are involved in their integration, and the merits of various design alternatives that present themselves. This thesis is the result of such an investigation and culminates in the presentation of a detailed architectural model that is validated with a prototypical implementation in an open source testbed. The model is built on six requirements which emerge from an analysis of the literature, including previous interventions in IMS networks and a key technical report on design alternatives. Furthermore, this thesis argues that the client architecture requires support for web-oriented signalling, identity and call handling techniques leading to a potential for IMS networks to natively support these techniques as operator networks continue to grow and develop. The proposed model advocates the use of SIP over WebSockets for signalling and DTLS-SRTP for media to enable one-to-one communication and can be extended through additional functions resulting in a modular architecture. The model was implemented using open source tools which were assembled to create an experimental network testbed, and tests were conducted demonstrating successful cross domain communications under various conditions. The thesis has a strong focus on enabling ordinary software developers to assemble a prototypical network such as the one that was assembled and aims to enable experimentation in application use cases for integrated environments.
- Full Text:
- Date Issued: 2018
Developing a cross platform IMS client using the JAIN SIP applet phone
- Authors: Muswera, Walter Tawanda
- Date: 2015
- Subjects: Internet Protocol multimedia subsystem , Java (Computer program language)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4712 , http://hdl.handle.net/10962/d1017934
- Description: Since the introduction of the IP Multimedia Subsystem (IMS) by the Third Generation Partnership Project (3GPP) in 2002, a lot of research has been conducted aimed at designing and implementing IMS capable clients and network elements. Though considerable work has been done in the development of IMS clients, there is no single, free and open source IMS client that provides researchers with all the required functionality needed to test the applications they are developing. For example, several open and closed source SIP/IMS clients are used within the Rhodes University Conver- gence Research Group (RUCRG) to test applications under development, as a result of the fact that the various SIP/IMS clients support different subsets of SIP/IMS features. The lack of a single client and the subsequent use of various clients comes with several problems. Researchers have to know how to deploy, configure, use and at times adapt the various clients to suit their needs. This can be very time consuming and, in fact, contradicts the IMS philosophy (the IMS was proposed to support rapid service creation). This thesis outlines the development of a Java-based, IMS compliant client called RUCRG IMS client, that uses the JAIN SIP Applet Phone (JSAP) as its foundation. JSAP, which originally offered only basic voice calling and instant messaging (IM) capabilities, was modified to be IMS compliant and support video calls, IM and presence using XML Configuration Access Protocol (XCAP).
- Full Text:
- Date Issued: 2015
- Authors: Muswera, Walter Tawanda
- Date: 2015
- Subjects: Internet Protocol multimedia subsystem , Java (Computer program language)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4712 , http://hdl.handle.net/10962/d1017934
- Description: Since the introduction of the IP Multimedia Subsystem (IMS) by the Third Generation Partnership Project (3GPP) in 2002, a lot of research has been conducted aimed at designing and implementing IMS capable clients and network elements. Though considerable work has been done in the development of IMS clients, there is no single, free and open source IMS client that provides researchers with all the required functionality needed to test the applications they are developing. For example, several open and closed source SIP/IMS clients are used within the Rhodes University Conver- gence Research Group (RUCRG) to test applications under development, as a result of the fact that the various SIP/IMS clients support different subsets of SIP/IMS features. The lack of a single client and the subsequent use of various clients comes with several problems. Researchers have to know how to deploy, configure, use and at times adapt the various clients to suit their needs. This can be very time consuming and, in fact, contradicts the IMS philosophy (the IMS was proposed to support rapid service creation). This thesis outlines the development of a Java-based, IMS compliant client called RUCRG IMS client, that uses the JAIN SIP Applet Phone (JSAP) as its foundation. JSAP, which originally offered only basic voice calling and instant messaging (IM) capabilities, was modified to be IMS compliant and support video calls, IM and presence using XML Configuration Access Protocol (XCAP).
- Full Text:
- Date Issued: 2015