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Now showing items 28-47 of 47
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Naidoo, Vaughn; Tucker, William D. (Telkom, 2001)[more][less]
Abstract: Next Generation Networks use policy-based network management and QoS protocols to provide voice services on IP networks. Large numbers of older equipment still push IP packets. We present several solutions that include legacy equipment into a PBNM and QoS system. A static design uses traffic shaping at the legacy edge. A dynamic solution uses a Quasi-PEP implemented over RSVP and COPS. Preliminary test results are presented for the static solution. Collected data shows that the solution decreases packet loss on the legacy side. URI: http://hdl.handle.net/10566/519 Files in this item: 1
NaidooTuckerNextGenNetworks2001.pdf (59.43Kb) -
Glaser, Meryl; Tucker, William D.; Mashao, Daniel (Telkom, 2004)[more][less]
Abstract: Following on the development of several prototypes, we have built a semi-automated Deaf Telephony prototype on the SoftBridge platform. This prototype relays text and speech between Deaf users on the Internet and hearing users on the telephone system. Previous work with a pilot trial in the laboratory revealed several opportunities for enhancement. We added a Wizard of Oz (WoOz) to replace the poorly performing automatic speech recognition functionality as well as H.323 breakout, more extensive logging and advanced call initiation functionality. In order to trial the current prototype, we initiated an Information and Communication Technology (ICT) training programme with the Deaf Community of Cape Town. Twenty Deaf users participated in the training. In addition to the training, much baseline user data was collected to give an indication of how Deaf users communicate with hearing users as well as how familiar they are with ICT devices and services. The work for the rest of this year requires us to recruit and train a WoOz operator. Subsequent trials will essentially consist of monthly cycles of prototype introduction, training, automated metric and log collection, user feedback and then feature enhancement. Linguistic analyses of the text output of the Deaf users will be analyzed. We hope to refine the SoftBridge prototype to fit the needs of the Deaf and hearing users, from both technical and social viewpoints. We expect that these iterative cycles will continue for some time and will teach us many lessons regarding multi-modal semi-synchronous IP-based communications systems. URI: http://hdl.handle.net/10566/447 Files in this item: 1
GlaserTuckerMashaoDeafTelephony2004.pdf (133.0Kb) -
Segers, Vaughn; Connan, James (2009)[more][less]
Abstract: This paper discusses an implementation for gesture recognition using eigenvectors under controlled conditions. This application of eigenvector recognition is trained on a set of defined hand images. Training images are processed using eigen techniques from the OpenCV image processing library. Test images are then compared in real-time. These techniques are outlined below. URI: http://hdl.handle.net/10566/63 Files in this item: 1
Segers_Real2009.pdf (179.9Kb) -
Tucker, William D.; Blake, Edwin H.; Marsden, Gary; Pearson, Murray; Westerveld, Rudi (Telkom, 2007)[more][less]
Abstract: This paper reports on three years of research and fieldwork with a rural wireless Internet Protocol communication project. We built a long-range WiFi network and custom communication software to support a rural telehealth project in the remote Eastern Cape. We report on our work using cellular networks, devices and applications as reference technologies because our users and beneficiaries are very comfortable with them. Of most concern are the technological and contextual issues affecting take up of the systems we designed. The paper intends to provide a summary analysis of our experience so that others in the field can learn from our successes and mistakes with respect to rural Information and Communication Technology for Development (ICT4D) in a South African context. URI: http://hdl.handle.net/10566/487 Files in this item: 1
TuckerIP-Communication2007.pdf (1.427Mb) -
Daniels, Francois; Tucker, William D. (Telkom, 2008)[more][less]
Abstract: This paper presents a fully decentralised peer-topeer voice communication tool intended for use across mobile ad hoc networks (MANET) by distributed groups who desired collaboration. We examined the synergy between MANETs and peer-to-peer virtual overlay networks which allowed the creation of ad hoc applications. One style of communication considered suitable for task oriented distributed group collaboration was push-to-talk. This research was focused on providing a push-to-talk communication platform suitable for deployment across MANETs. The research methodology employed was a proof of concept approach within a classical experimental computer science paradigm. We developed a prototype which used JXTA, a peer-to-peer virtual overlay network, to provide push-to-talk functionality across MANETs. Guaranteed delivery of messages was provided via a peer-to-peer voicemail delivery system. While the system did what intended we show that JXTA had a problem with the efficient delivery of voice samples. URI: http://hdl.handle.net/10566/508 Files in this item: 1
DanielsTuckerMANET2008.pdf (216.0Kb) -
Tucker, William D.; Blake, Edwin H. (International Information Management Corporation, 2008)[more][less]
Abstract: We describe the use of Outcome Mapping to guide the design of a rural telemedicine consultation system in South Africa. While Outcome Mapping was not primarily intended to guide design, we show that it tied in well with a cyclical participatory design method for an Information and Communication Technology for Development project. URI: http://hdl.handle.net/10566/525 Files in this item: 1
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Poroye, Adeola; Tucker, William D.; Norman, Michael (Telkom, 2009)[more][less]
Abstract: This paper presents work in progress to explore the utility of Near Field Communication technology to secure mobile financial services. The objective is to evaluate the potential of this approach as an upcoming technology for mobile cash transactions. The paper argues that Near Field Communication technology offers a feasible solution and can be integrated into a standard cellular handset to turn it into a contactless smart card. The motivation is to create a new secure way for the unbanked to perform financial transactions. A prototype has been developed and tested with participants in a laboratory environment. This paper also reports on preliminary results. URI: http://hdl.handle.net/10566/540 Files in this item: 1
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Wu, Wilson; Radovanovic, Aleksandar; Tucker, William D. (Telkom, 2005)[more][less]
Abstract: This paper presents an innovative use of the Session Initiation Protocol (SIP) for the subscription and notification of geographic information in order to provide a privacy concerned location-based service. SIP is a signaling protocol used for establishing sessions in an IP network. It has been widely used for Internet conferencing and telephony. This research project aims to enhance the SIP presence model in order to protect sensitive geographic information. To achieve this goal, we thoroughly analyzed existing Location-Based Services (LBS), reviewed LBS designs’ pitfalls and identified several key privacy requirements. Based on this research, we presented a SIP flow that meets the privacy requirements. This SIP message flow includes SUBSCRIBE, NOTIFY and PUBLISH messages. A data format to carry geographic location information has also been introduced. The data format is based on Presence Information Data Format (PIDF). We define it as Location-enhanced PIDF, or LPIDF. LPIDF contains geographical information objects. We hope that the outcome of this research project will provide rich, convenient, privacy concerned architecture for LBS. Because LPIDF is based on SIP, this approach can be easily integrated into IP telephony services. LPIDF enables personalization of the Location-Based services address user privacy concerns and hereby increase their satisfaction. URI: http://hdl.handle.net/10566/494 Files in this item: 1
WuRadovanovicTuckerSIP2005.pdf (385.7Kb) -
Kobo, Hlabishi Isaac; Tucker, William D. (IIMC International Information Management Corporation, 2012)[more][less]
Abstract: This paper describes a situation-aware algorithm based on the current situation of a mesh network with mobile nodes that improves quality of service. After running laboratory performance tests, we concluded that a situation-aware mesh routing protocol offers potential to address issues pertaining to mobility, congestion and scalability in dynamic mesh networks with mobile nodes. Such networks appear promising to provide connectivity to people living in rural areas in developing regions of Africa, and can be easily interconnected to telco-styled networks through gateways for voice and Internet services. Such services can remain free in the mesh, yet can also be billed for interconnection. Our vision offers an attractive business model for up scaling a rural customer base for telcos, while at the same time offering increased quality of service for mobile users on rural mesh networks. URI: http://hdl.handle.net/10566/585 Files in this item: 1
KoboTuckerISTAfrica2012.pdf (465.0Kb) -
Roro, Zukile; Rey-Moreno, Carlos; Tucker, William D.; Siya, Masbulele Jay (Telkom, 2012)[more][less]
Abstract: This paper describes work in progress towards developing a business case and preliminary design for an 802.11-based mesh network in the remote rural community of Mankosi in the Eastern Cape province of South Africa. Aside from the technical challenges to building the network to be sustainable in the long term, this network needs to generate some revenue. Hence, there needs to be a business model that has revenue generation potential. This study will explore the economical and social aspects of voice over Internet- Protocol as a service for this community. After talking to the village leaders, we learned that there is a demand for telecommunication services and that most of them were interested only in telephony service. Very few villagers were interested in or had any knowledge about the Internet. We also learned that most of their cellular phone calls are local within the Mankosi community. This allows us to deploy an experimental local telephony service; a perfect opportunity for a low-cost and lowcosting inverse mesh infrastructure that can easily be connected to breakout and Internet services in the future. URI: http://hdl.handle.net/10566/594 Files in this item: 1
RoroRey-MorenoTuckerSiya-SATNAC2012.pdf (150.8Kb) -
Lewis, John; Tucker, William D.; Blake, Edwin H. (Telkom, 2003)[more][less]
Abstract: Instant Messaging is traditionally a text only a air. However, there are instances when it would be useful to bridge to other types of media, like speech. The SoftBridge is an application framework that enables this kind of communications bridging using instant messages. Its use of protocols like the Jabber Instant Messaging Protocol and the Simple Object Access Protocol makes it simple, open and extensible. It also allows bridging to non IP communications infrastructure, like the telephone network. We describe the design and architecture of the system, protocol and extensibility mechanism. Finally we describe our experimental methodology and discuss the results of our initial experiments. URI: http://hdl.handle.net/10566/537 Files in this item: 1
LewisTuckerBlakeInstantMessaging2003.pdf (202.4Kb) -
Lewis, John; Tucker, William D.; Blake, Edwin H. (Telkom, 2002)[more][less]
Abstract: Users and computing equipment have varying capabilities that include the abilities to exchange text and audio, engage in high bandwidth communication, etc. As the technological options increase, e ective communication between the di erent media has be able to bridge across these options: the bridges have to take into account network quality, end-user equipment capabilities as well as user preferences and capabilities. Our research proposes a Soft- Bridge, an abstracted communications platform for the construction of applications across disparate capabilities found in various Digital Divides. We outline the architecture and the requirements that the SoftBridge has to ful ll. An approach and some initial work is described. URI: http://hdl.handle.net/10566/606 Files in this item: 1
LewisTuckerBlake-SATNAC2002.pdf (126.3Kb) -
Tucker, William D.; Glaser, Meryl; Lewis, John (Telkom, 2003)[more][less]
Abstract: Following on several partial prototypes, we built an automated Deaf Telephony bridging application with the SoftBridge platform. The SoftBridge performs multi-modal bridging in real-time using Text-to-Speech (TTS) and Automatic Speech Recognition (ASR) utilities accessed via web services. To perform Action Research with the Deaf community in Cape Town, we invited a Deaf user (DU) to participate in a pilot study. We conducted three tests varying the input/output modalities of the hearing user (HU). The DU had a standard text in/text out Instant Messaging client. The HU client used the following specific modality combinations: Text & TTS in/Text out, TTS in/Text out and TTS in/Text & ASR out. The SoftBridge logged the conversations for subsequent analysis. The trial showed a largely successful conversation. Success factors include a) a text and computer literate DU who is familiar with research practise, b) using the system to explain the research as we conducted it and c) that the multi-modal bridging capabilities overcame the expected shortcomings of TTS and especially ASR. The lessons learned from this trial will be applied to the next trial once the necessary modifications have been implemented. URI: http://hdl.handle.net/10566/535 Files in this item: 1
TuckerDeafTelephony2003.pdf (108.8Kb) -
Sun, Tao; Tucker, William D. (Telkom, 2004)[more][less]
Abstract: We have built a SoftBridge prototype within a JAIN (Java APIs for the Integrated Network) SLEE (Service Logic Execution Environment). A SoftBridge is a semi-synchronous multimodal IP (Internet Protocol) -based communication system and the first prototype has been built for deaf telephony. This research addresses service life-cycle management for a SoftBridge with carrier grade reliability. An approach is proposed that carrier grade reliability support for a SoftBridge is provided by moving it into a JAIN SLEE. A JAIN SLEE is a general application server, which provides execution and management environment for telecommunication services. An empirical evaluation methodology is adopted to verify that JAIN SLEE enables carrier grade support for a SoftBridge. This work includes the development of functions of a SoftBridge and life-cycle management of a SoftBridge within a JAIN SLEE. Current work is busy in developing multimodal media adaptation functions of the SoftBridge prototype. System test, experiments with PBX (Private Branch Exchange)/PSTN (Public Switched Telephone Network) and evaluation of the SoftBridge prototype will be carried out in the next steps. Carrier grade reliability enables a SoftBridge to access the PSTN. A highly reliable SoftBridge could bring more new value-added services for telecom providers. Using a SoftBridge as an example, we also can learn how to go about carrier grade enhancement for IP-based communication applications in the telecoms domain. URI: http://hdl.handle.net/10566/592 Files in this item: 1
SunTucker-SATNAC2004.pdf (66.62Kb) -
Ghaziasgar, Mehrdad; Connan, James (2008)[more][less]
Abstract: Current wireless human-computer interaction devices such as wireless mice and touchscreens, by and large, incorporate a sophisticated electronic architecture. The sophistication achieves wireless capabilities but carries over a cost overhead. In this paper we lay the foundation for developing a novel human-computer interaction device with reduced hardware sophistication. We developed a surface acoustic wave touchscreen-type device using only two transducers, as opposed to, typically, three or more transducers in conventional surface acoustic wave touchscreens. The transducers are mounted on a glass surface and connected into the line-in of a stereo sound card. User-initiated taps are detected, analysed and located on the surface, and the mouse cursor is moved to the computed screen location. URI: http://hdl.handle.net/10566/54 Files in this item: 1
Ghaziasgar_Surface(2008).pdf (454.3Kb) -
Glaser, Meryl; Tucker, William D. (2004)[more][less]
Abstract: This paper presents a description of telecommunications for Deaf people in South Africa by contrasting the situation in the developed world. We explain the main motivations for providing a locally appropriate solution. Research activity began with a community-based field trial of TTYs. The recommendations of the trial motivated an innovative approach to provide synchronous and accessible relay services. Drawing from international technological developments, we designed a software solution called the SoftBridge. We employ iterative Action Research cycles to drive technological modifications to the SoftBridge and to encourage adoption by the end-user community. URI: http://hdl.handle.net/10566/593 Files in this item: 1
GlaserTucker-CVHI2004.pdf (162.9Kb) -
Chetty, Marshini; Tucker, William D.; Blake, Edwin H. (Telkom, 2004)[more][less]
Abstract: Rural areas in South Africa have unique conditions such as remoteness and scarcity of reliable public facilities. Information and Communication Technologies (ICTs) introduced into these areas must be suitable for these conditions. Using a user-centred design approach based on Participatory Design and Action Research, we have developed a telemedicine application for a rural village in the Eastern Cape. This paper describes how we determined the requirements and design for the application and why we chose Voice over Internet Protocol (VoIP) combined with a store and forward approach to achieve our telemedicine goals. We present an overview of the methodology we are using, describe the software application we have developed and mention several challenges we have faced to date. Finally we conclude that VoIP and store and forward technologies are appropriate to the South African rural situation. URI: http://hdl.handle.net/10566/621 Files in this item: 1
ChettyTuckerBlake-SATNAC2004.pdf (287.0Kb) -
Penton, Jason; Tucker, William D.; Glaser, Meryl (Telkom, 2002)[more][less]
Abstract: We have developed a prototype bridge that relays text and speech between Teldem, a text telephone for the Deaf, and a standard telephone or H.323 endpoint. Telgo323 uses modified H.323 media gateways and open source Text to Speech and Speech to Text software. The approach allows for easy integration of new tools as the technologies mature. This paper presents the design of the implementation prototype, discusses Teldem tone decoding, and suggests directions for future work. The Telgo323 provides evidence that an automated relay bridge is imminently viable for the Deaf Community, and further demonstrates an attractive approach for building bridges over the Digital Divide. URI: http://hdl.handle.net/10566/612 Files in this item: 1
PentonTuckerGlaser-SATNAC2002.pdf (99.60Kb) -
Chetty, Marshini; Tucker, William D.; Blake, Edwin H. (Telkom, 2003)[more][less]
Abstract: There is a great disparity between those who have access to Information and Communication Technologies (ICTs) and those that do not. This phenomenon forms part of the Digital Divide. Many ICTs may be used to help overcome this divide if they are applied in a useful way, providing locally applicable content and services. Critical Action Research (CAR) is an approach used to develop such applications. CAR aims to empower people by involving them in the development process. Using CAR, this project investigates how Voice over IP (VoIP) may be applied in a productive way in an underserviced community. VoIP is an ICT used for sending voice over packet switched networks using Internet Protocol. It can be used to integrate data and voice to produce multimedia applications. In South Africa (SA), VoIP may only be provided by Telkom, the Second National Operator and the Under-Serviced Area Licensees. Using CAR and VoIP, an application is being developed to service a specific need of a particular rural community. The application will either provide a service to a small rural business or aid the provision of healthcare in rural areas. The project evaluates how well CAR integrates with a normal Software Development Lifecycle and makes policy recommendations for the use of VoIP in rural SA. URI: http://hdl.handle.net/10566/479 Files in this item: 1
ChettyTuckerBlakeDigitalDivide2003.pdf (35.78Kb) -
Glaser, Meryl; Tucker, William D. (Telkom, 2001)[more][less]
Abstract: A Teldem provides text-based telephony services to the deaf. Despite an array of text-based communications mechanisms on the web, the Teldem is the only means of synchronous telecommunication available to a deaf person. We examine a human-assisted relay that provides a bridge between the deaf and the hearing, and then propose several additional bridges. These bridges take advantage of both standard and cutting edge technologies. We present each bridge's impact on the deaf with respect to synchrony, connectivity, independence, and the Digital Divide. It is hoped that by deploying trials for each bridge, we can eventually provide the deaf with equal access. URI: http://hdl.handle.net/10566/613 Files in this item: 1
GlaserTucker-SATNAC2001.pdf (146.9Kb)
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Now showing items 28-47 of 47