Southern Africa Telecommunication Networks and Applications Conference (SATNAC) 2011 4 - 7 September 2011 East London Convention Centre, South Africa

Abstract Booklet

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Social Communications – Challenging the Limits of Technology Innovation Venue: East London Convention Centre, East London, South Africa Date: 4 - 7 September 2011 Publication Information Title: SATNAC 2011 Abstract Booklet Editor: Dr Stefan Scriba (Telkom) Date of print: August 2011 Version: First Edition SATNAC is the flagship of the Telkom Centre of Excellence (CoE) Programme.

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Table of Contents SATNAC 2011 Conference Sponsors ...................................................................................................... iv

SATNAC 2011 Review Process ................................................................................................................. v

Organising Committee ........................................................................................................................... vi

Technical Programme Committee ......................................................................................................... vi

Technical Reviewers .............................................................................................................................. vii

Access Network Technologies ................................................................................................................ ix

Internet Services & Applications ............................................................................................................ xi

Network Engineering ........................................................................................................................... xiii

Network Management & OSS ...............................................................................................................xiv

Network Planning and Optimization ..................................................................................................... xv

Network Services ..................................................................................................................................xvi

Optical Transport and Core Networks ................................................................................................ xviii

Protocols ............................................................................................................................................. xviii

Software .................................................................................................................................................xx

Standardisation Initiatives, Innovation & Regulatory ........................................................................... xxi

The Intelligent IP Edge ......................................................................................................................... xxii

Work In Progress: Access Network Technologies ............................................................................... xxiii

Work In Progress: Internet Services & Applications ........................................................................... xxiv

Work In Progress: Network Services .................................................................................................... xxv

Work In Progress: Software ................................................................................................................ xxvi

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SATNAC 2011 Conference Sponsors The SATNAC 2011 Committee would like to recognize the following sponsors:

Diamond Sponsors

Platinum Sponsors

Gold Sponsors

Silver Sponsors

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SATNAC 2011 Review Process A formal ‘Call for Papers’ was issued, inviting anyone interested to submit a paper within categories specified by the Organizing Committee. Authors uploaded their papers via web interface onto a database. Papers were assigned to the review panel in the field to judge on the possible acceptance of the submission, based on the scope and depth of the subject matter. The review process is based on the international de facto standard for blind paper reviews. The review process was undertaken by at least three experienced and well respected individuals. In the blind peer-review process, papers were scrutinized by a panel of South African reviewers, consisting of mainly respected academics, as well as several international experts. The reviewers were asked to provide specific feedback, both positive and negative. This was the only information from the review process disclosed to the authors; all other information was kept confidential. Reviewers used a 5 point scale to rate the following criteria:

• Originality • References • Technical Quality • Presentation Style • Relevance

Reviewers gave an overall rating. This was followed by the reviewer comments, which assists the authors in improving and correcting their papers. Reviewers were asked to be as comprehensive as possible. The reviewers submitted their scoring and comments via web interface onto the database. The Technical Programme Committee drew reports and aggregated the individual scores. The papers were ranked on their average weighted score. The programme dictated the number of papers that could be accepted. Papers were submitted to an online plagiarism database, before being accepted. The reviewers’ comments were forwarded to the author’s, with a request to submit a final revised version. Only those papers of high enough quality as recommended by the respective reviewers are included in the SATNAC 2011 Proceedings as Full Reviewed Papers. Two page Work-In-Progress papers were also invited but were not reviewed as rigorously. Several were accepted for oral presentations, while others for poster presentations. The poster session papers do not form part of the official conference proceedings.

Dr Stefan Scriba Chairperson Technical Programme Committee SATNAC 2011

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Organising Committee Marius Mostert (Chairperson) Gys Booysen Marti Beukes Alphonzo Samuels Andrew Heuvel Dudley Crotz

Technical Programme Committee Dr. Stefan Scriba (TPC Chairperson), Telkom SA Mr. Gys Booysen, Telkom SA Mr. Mohamed Abdelatif, Telkom SA Prof. Mathew Adigun, University of Zululand Dr. Rolan Christian, KPMG Dr. Willem Clarke, University of Johannesburg Dr. Lester Cowley, Nelson Mandela Metrolpolitan University Mr. Sabelo Dlamini, Telkom SA Mr. Ian Durston, Telkom SA Mr. Grant Evert, Telkom SA Mr. Alan Huang, Telkom SA Dr. Richard Good, Smile Technologies Mr. Nishkar Govender, Ericsson Prof. Richard Harris, Massey University Mr. Jeff Hinds, MWEB Prof. Hennie Kruger, North-West University Prof. Tony Krzensinski, University of Stellenbosch Mr. Anish Kurien, Tshwane University of Technology Dr. I-Sheng Liu, Ericsson Mr. Keoikantse Marungwana, Telkom SA Dr. Thomas Niesler, University of Stellenbosch Mr. Mario Paes, Telkom SA Prof. Roger Peplow, University of KwaZulu-Natal Prof. Christo Pienaar, Vaal University of Technology Mr. Claude Prinsloo, Telkom SA Mr. Abri Rozendaal, Telkom SA Mr. Jaco Schutte, Telkom SA Dr. Mamello Thinyane, University of Fort Hare Prof. Rex van Olst, University of Witwatersrand Mr. Conroy Smith, Telkom SA Prof. Alfredo Terzoli, Rhodes University Mr. Hennie van Tonder, Telkom SA Mr. Jacques van Wyk, University of Pretoria Prof. Isabella Venter, University of the Western Cape Mr. Neco Ventura, University of Cape Town Mr. Frans-Willem Vermaak, Telkom SA Dr. David Waiting, Telkom SA Dr. James Whitehead, Natcom Ms. Phillippa Wilson, Telkom SA

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Technical Reviewers Abel Ajibesin, University of Cape Town Antoine Bagula, University of Cape Town Rob Benyon, Rhodes University Edwin Blake, University of Cape Town Marthinus Botha, University of Pretoria Karen Bradshaw, Rhodes University Andre Calitz, Nelson Mandela Metropolitan University Dr. Ling Cheng, University of Witwatersrand Tapiwa Chiwewe, University of Pretoria Charmain Cilliers, Nelson Mandela Metropolitan University James Connan, Rhodes University Lorenzo Dalvit, Rhodes University Reg Dodds, University of Western Cape Olabisi E Falowo, University of Cape Town Nikolai de Figueiredo, University of Pretoria Joubert de Wet, North West University Karim Djouani, Tshwane University of Technology Mqhele E. Dlodlo, University of Cape Town Kevin Duff, Rhodes University Melvin Ferreira, North West University Richard Foss, Rhodes University Mehrdad Ghaziasgar, University of Western Cape Dr. Eugene Golovins, Riga Technical University Leenta Grobler, North West University Stefan Gruner, University of Pretoria Prof. Albert Helberg, North West University Gertjie Hoffman, North West University Barry Irwin, Rhodes University Edgar Jembere, Zululand University Christo Kleu, University of Pretoria Kritzinger, University of Cape Town Hanh Le, University of Cape Town Wilhelm Leuschner, North West University Mathe Maema, Rhodes University Yskander Hamam, Tshwane University of Technology Gary Marsden, University of Cape Town Alexander Merensky, University of Pretoria Yusuf Moosa Motara, Rhodes University Pragasen Mudali, Zululand University Alexandry Murgu, University of Cape Town Muhana Muslam, University of Cape Town Bethel Mutanga, Zululand University Joyce Mwangama, University of Cape Town Mjumo Mzyece, Tshwane University of Technology Joyce Namakoye, University of Witwatersrand Prof. A Nel, University of Johannesburg Michael Norman, University of Western Cape Alastair Nottingham, Rhodes University H O Nyongesa, North West University Charl Opperman, University of Pretoria

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Dr. Khmaies Ouhada, University of Johannesburg Narushan Pillay, University of KwaZulu-Natal Jide Julius Popoola, University of Witwatersrand Thinus Prinsloo, University of Pretoria Dr. Tahmid Quazi, University of KwaZulu-Natal Aveer Ramnath, University of Witwatersrand Rathilall Sewsunker, University of KwaZulu-Natal Kamil Reddy, University of Pretoria Seare Rezenom, University of KwaZulu-Natal Evan Saunders, Telkom SA Khulumani Sibanda, Rhodes University Ingrid Sieborger, Rhodes University Boyan Soubachov, University of Cape Town R Spiers, University of Cape Town Hussein Suleman, University of Cape Town Dr. TG Swart, University of Johannesburg Adam Swiatko, University of Pretoria Fanie Terblanche, North West University Hannah Thinyane, Rhodes University Mamello Thinyane, Rhodes University Robin Thomas, University of Pretoria Melekam Tsegaye, Rhodes University Mosiuoa Tsietsi, Rhodes University Ryan vd Bergh, University of Witwatersrand Dr. Jaco Versfeld, University of Witwatersrand Sune von Solms, North West University Dr. Tom Walinga, University of KwaZulu-Natal George Wells, Rhodes University Peter Wentworth, Rhodes University R. Wertlen, Rhodes University Janet Wesson, Nelson Mandela Metropolitan University Riaan Wolhuter, Stellenbosch University Madeleine Wright, Rhodes University

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SATNAC 2011 Technical Programme

Access Network Technologies Title: 132: Fast handovers without DAD using Sector-based Vehicular Mobile IPv6 Authors: Laurence Banda (French South African Institute of Technology), Mjumo Mzyece (Tshwane University of

Technology) and Guillaume Noel (Tshwane University of Technology) Abstract: “One of the major challenges faced in vehicular networks is the provision of seamless and continuous IP

connectivity for on-board Internet users. This mainly emanates from long handover delays and packet loss problems. These hiccups can have severe effects such as Quality of Service (QoS) depreciation for delay-sensitive and throughput-sensitive services like real-time multimedia services. Most current IP mobility management solutions focus on pedestrian mobile users moving with relatively low speeds and thus fail to provide mobility support for high mobility nodes in vehicular networks. In this paper, we theoretically formulate a Network Layer Fast handover scheme in vehicular networks without Duplicate Address Detection (DAD) using sector based Vehicular Mobile IPv6. Sectorisation of radio coverage cells and Global Positioning Systems (GPS) mounted on vehicles aid in accurately predicting vehicle directions. The fast discovery of the target Access Router (AR) and the total elimination of DAD procedure could reduce the handover latency and packet losses thereby improving the overall QoS in vehicular networks.”

Title: 135: Influence of a Realistic Loading on Characteristics and Design of ESPAR Authors: Albert Lysko (CSIR Meraka Institute) and Mofolo Mofolo (University of Johannesburg) Abstract: “The paper presents results of a study considering a 2.4 GHz low-cost low-power-consumption electronically

switched parasitic array radiator (ESPAR) antenna suitable for wireless sensor networks and rural applications. The paper discuses the effects of realistic versus ideal loads in the process of modeling and design on the example of a four plus one elements antenna. The realistic loading is found to have a significant effect on the design, e.g. reducing the gain by over 2 dB and the return loss by up to 6 dB. The paper presents several optimized designs, offering gain of 9 dBi and excellent impedance match.”

Title: 148: A Multi-levelled OFDM-CDMA Modem Using Complete Complementary Codes Authors: Alexander Merensky (University of Pretoria), Jacques Van Wyk (University of Pretoria) and Louis Linde

(University of Pretoria) Abstract: "In this paper, we introduce a novel multiple access scheme based on a combination of a multi-levelled modem

and multi-carrier techniques with the use of complete complementary codes. The modulation technique combines a multi-dimensional code division multiple access (CDMA) modem with recent designs of perfectly complete complementary orthogonal codes. The rotational properties of the spreading codes are further exploited to improve the modulation technique, throughput, spectral efficiency, and capacity. Additionally, the system is extended by making use of multiple carrier frequencies as in OFDM, with the additional benefits of being able to spread data in frequency and/or in time. The modem offers multiple access interference MAI-free and multipath interference MI-free operation in both asynchronous and synchronous communication, due to perfect autocorrelation and zero cross-correlation properties of the spreading codes. The unique multi-levelled multiple access modulation technique together with the integration of complete complementary codes, produces a spectrally efficient output signal with high data throughput rates, better noise tolerances in harsh channel conditions and an increased user capacity."

Title: 153: High-Rate Non-Binary Product Codes Authors: Farzad Ghayour (University of KwaZulu-Natal), Fambirai Takawira (University of KwaZulu-Natal), Hongjun Xu

(University of KwaZulu-Natal) Abstract: "Research has shown that the random codes with a long block length are more likely to approach the channel

capacity. One approach for designing a long length code with reasonable complexity is to combine two or more short length codes with each other and generate a code with a long block length size. In this paper we are investigating on the non-binary product codes which have been constructed from combination of two non-binary single parity-check (SPC) codes as their component codes. Designing a high-rate code with these types of codes is feasible and can be done by tending the length of the code towards infinity. The construction and decoding of the non-binary SPC product codes when the SPC codes are defined over a finite field of order q, as well as when they are defined over an integer residue ring of order q have been studied and the simulation results have been represented."

Title: 159: A Handover Scheme for Mobile WiMAX Authors: Mary Alatise (French South African Institute of Technology), Mjumo Myzece (Tshwane University of

Technology) and Anish Kurien (Tshwane University of Technology) Abstract: "Abstract- The addition of mobility to the WiMAX standard through 802.16e has made the standard more

flexible and potential choice as a wireless broadband technology. To support mobility in any wireless scheme, the application of effective handover control schemes is crucial. Any delay experienced during data transmission in hard handover in mobile network could cause handover delays with potential connection drops. In other to solve the problem of handover delay, various types of handover schemes have been adopted. This paper proposes the combining of the Relative Signal Strength with Threshold and Hysteresis and Distance (RSTH-D) to initiate handover. Distance is considered as a criterion to perform handover faster. This scheme seeks to reduce handover delay which contributes to effective radio resources management. It is shown through results obtained that the proposed scheme has potential performance benefits compared to standard handover schemes."

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Title: 167: Carrier detection of FM signals using the Wideband Compressive Radio Receiver Authors: Sarel Joubert (North-West University), De Wet (North-West University) and Albert S. J. Helberg (North-West

University) Abstract: "The Wideband Compressive Radio Receiver (WCRR) is a wideband receiver based on the field of

Compressive Sensing (CS), which enable signal acquisition at rates less than the traditional Nyquist. In this paper we present a model of the WCRR for wideband received signals consisting of FM Signal of Interests (SoIs). We use this model to study the effect of different combinations of window length N and decimation factor L on the performance of carrier detection. We also test the robustness of the carrier detection method to noise. Finally we compare the results obtained with our previous results where the received signal consisted of unmodulated carriers. We find that longer windows result in higher decimation factors and that the system is robust to noise."

Title: 172: An Efficient Connection Admission Control (CAC) for QoS Provisioning in IEEE 802.16 Authors: Samuel Kehinde Falowo (University of Cape Town) and Neco Ventura (University of Cape Town) Abstract: "Abstract-Service differentiation and QoS support are important aspects of connection admission control (CAC)

in IEEE 802.16 networks which is left for vendors to design and implement for efficient resource utilization. In this paper a bandwidth based dynamic control threshold (DT) is proposed for the connection types of IEEE 802.16 networks. The threshold is used to differentiate and prioritize connection types according to QoS requirements. The control threshold changes dynamically in order to respond to the varying traffic of connections. A performance analysis model based on Markov chains is proposed and numerical results are presented to demonstrate the performance of the proposed scheme. The scheme when compared with bandwidth partitioning scheme performs better in terms of blocking probability."

Title: 189: Comparative Study of Web Services Platforms in a GUISET Environment Authors: Ijeoma Noella Mba (University of Zululand) and Matthew O Adigun (University of Zululand) Abstract: "GUISET architecture aims at delivering e-services to resource-constrained SMMEs by taking advantage of

advances and trends toward Service Oriented Architecture (SOA) within the software industry. A technology that has received widespread adoption within SOA for implementing services is Web Services (WS). However, Web Services’ success has been facilitated by implementation of core WS-Standards into enterprise application development platforms and tools within both the proprietary and Open Source Communities. Although, for the target group of GUISET (SMMEs), the Open Source platforms seem a natural choice as proprietary tools are often expensive and are out of their reach. But, even within the open source communities are many platforms with different characteristics and features. A major challenge is how to choose the appropriate platform that is suitable for GUISET services scenario. One question that is crucial to addressing this challenge (especially within the context of GUISET): can a comparative study of existing Web Services development platforms be used in recommending one for GUISET services? This is the central goal of this research. Our aim is to benchmark the performance of a few leading open source web service platforms with a view to determine their suitability for developing GUISET services under an e-commerce scenario and use to recommend one for GUISET services."

Title: 191: Multi-Radio Access Selection to Reduce Reorder Buffer Requirements in Heterogeneous Wireless

Networks with Multi-homed Mobile Terminals Authors: Allen L. Ramaboli (University of Cape Town), Olabisi Falowo (University of Cape Town) and Anthony Chan

(University of Cape Town) Abstract: "Aggregating bandwidth from multiple radio access technologies (RATs) provides an opportunity for network

providers to enhance network capacity. This is important for serving applications that require more bandwidth than a single RAT can offer. One of the important elements of bandwidth aggregation is the selection of a suitable set of RATs to achieve efficient aggregation. In this paper, we propose a multi-radio access selection scheme for selecting an appropriate set of RATs to achieve the desired bandwidth aggregation for a connection request initiated by a multi-homed terminal in a heterogeneous wireless network. The objective of the proposed scheme is to reduce the need for packet reordering at the receiver minimized whenever possible. The operation of the proposed scheme is explained in details."

Title: 195: Analysis of the impact of some network parameters on the accuracy of RSS-based geometric

positioning methods Authors: Folasade Dahunsi (University of Witwatersrand), Barry Dwolatzky (University of Witwatersrand) and Anne Love

(University of Witwatersrand) Abstract: "The accuracy of Received Signal Strength (RSS)-based positioning methods is highly variable due to its

dependence on various varying parameters such as the wireless environment, topology of the network, propagation model utilized etc. In this paper, simulated data was analyzed to examine the effect distances and number of BSs used has on positioning accuracy based on four RSS-based geometric positioning methods. There is relatively varying differences that the topologies of the network have on the accuracy of the positioning algorithms. The RSS-based Geometric algorithms considered include the Centre of Gravity, the Centre of Trilateration, the Least Square and the Trilateration algorithms."

Title: 206: Evaluation of Gardner timing recovery in a land mobile satellite channel Authors: Gertjie Hoffmann (North-West University), Albert Helberg (North-West University) and Joubert De Wet (North-

West University) Abstract: "The performance of the Gardner timing recovery scheme is evaluated in a Markov-based land mobile satellite

channel model. Various different scenarios of the channel model are used to evaluate the timing recovery scheme. The performance of the scheme in the land mobile satellite (LMS) channel is compared to the performance of the scheme in a Gaussian channel. The results from this evaluation can be used to determine if the Gardner timing recovery scheme is suitable for LMS communication system. The results can be used to make a decision regarding coding schemes to be employed with this timing recovery scheme."

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Internet Services & Applications Title: 104: Investigating a Reduced Size Real-Time Transport Protocol for Low-Bandwidth Networks Authors: Josephine N. Kakande (CSIR), Keith L. Ferguson (University of Cape Town), Mqhele E. Dlodlo (University of

Cape Town) and Gerhard De Jager (University of Cape Town) Abstract: "Optimization of bandwidth usage for video streaming is of paramount importance in networks where low

bitrate links are typical. Among the solutions proposed to address this problem is header compression. Real-Time Transport Protocol (RTP) and RTP Control Protocol (RTCP) are the major protocols responsible for the delivery of real-time media. Previously, header compression at the hardware layer and multiplexing of media frames into single RTP packets was considered sufficient for reducing the bit overhead of the RTP packets. However, at the very low bit rates encountered in congested and low throughput networks, multiplexing and hardware compression do not suffice for end-to-end delivery and therefore the use of a lightweight version of RTP, defined in this work as RTP-Lite, requires investigation. A cyclical approach to compression of the RTP headers was used with different compression cycle patterns for Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) transport. Measurements over the public Internet showed that end-to-end compression of the RTP header at the application layer was achieved with the expected reduction in required throughput and minimal degradation of packet loss and jitter performance."

Title: 105: Real-Time Performance Evaluation of Media Pipeline Plug-in Architectures Authors: Veronica N. Sentongo (CSIR Meraka Institute), Keith Ferguson (University of Cape Town) and Mqhele Dlodlo

(University of Cape Town) Abstract: "Abstract- Deployment of real-time applications has become ubiquitous in recent years. These applications

(e.g. streaming audio and video over the Internet) however, are processor-intensive and require fast video-processing techniques for more flexible, efficient operation. Media pipeline plug-in architectures have been introduced to provide these capabilities in form of extensible, integrated frameworks. Several architectures are in existence and many future designs are expected. This paper serves to design a set of measurement metrics on which to base the comparative performance analysis of the real-time capabilities of two of them; DirectShow and GStreamer. This exemplifies the decision process through which a particular architecture can be isolated as that best suited for a specified real-time application. The metrics used are: average processing speed, plug-in scalability, threading overhead and programming complexity. Based on these metrics, effective comparison of other plug-in architectures can be made to determine their real-time performance in relation to a particular application."

Title: 106: Fast Implementation of Block Motion Estimation Algorithms in Video Encoders Authors: Rohini.N Koduri (University of Cape Town), Prof.Mqhele.E Dlodlo (University of Cape Town), Prof.Gerhard De

Jager (University of Cape Town) and Dr.Keith Ferguson (CSIR Meraka Institute) Abstract: "Block matching algorithms (BMA) are central to optimal frame prediction for motion estimation in video

compression. This paper focuses on the efficiency of Hierarchical Search (HS) algorithms. The research proposed two new combinations of fast algorithms like Small Diamond- shaped Search Pattern (SDSP) and Square-Shaped Search Pattern (SSSP) with a three- level Hierarchical algorithm at different levels of hierarchy. The computational complexity and efficiency for each combination algorithm were of interest. Simulation results show that the hierarchical combination algorithms are around 10% faster than the classic hierarchical algorithm with slight improvement or no significant change in video quality when compared to general HS algorithm."

Title: 161:Transparent and Reliable Computing Power Service Provision on P2P systems Authors: Ghislain Fouodji Tasse (Rhodes University) and Karen Bradshaw (Rhodes University) Abstract: "The advancements in virtualization technologies have provided a large spectrum of computational

approaches. Dedicated computations can be run on private environments (Virtual Machines), created within the same computer. Through capable APIs, this functionality is leveraged for the service we wish to implement; a computer power service (CPS). We target peer-to-peer systems for this service, to exploit the potential of aggregating computing resources. The concept of a P2P network is mostly known for its expanded usage in distributed networks for sharing resources like content files or real-time data. This study adds computing power to the list of shared resources by describing a suitable service composition. Taking into account the dynamic nature of the platform, this CPS provision is achieved through an on-the-fly clustering algorithm. Moreover, this service would be highly beneficial in a corporate environment."

Title: 178: Security of Cloud Computing: Seeing Through the Fog Authors: Moses Dlamini (University of Pretoria, SAP Research IA&S/Meraka UTD), Hein Venter (University of Pretoria),

Jan Eloff (University of Pretoria, SAP Research IA&S/Meraka UTD) and Mariki Eloff (University of South Africa) Abstract: "Cloud computing is a new computing paradigm for the provisioning, delivery and consumption of IT resources

and services on the Internet. This computing paradigm comes with huge benefits such as cost savings, increased resilience and service availability, improved IT operations efficiency and flexibility. However, most research cites security concerns as one of the biggest challenges for most of these organizations. This has led to fallacy or misconception about security challenges of the ‘cloud’ which needs to be clarified. This is a call for more research to separate reality from the hype. Hence, this paper aims to separate justified security concerns from the hype, fear of the unknown and confusion that currently prevails within cloud computing. This paper aims to advance the current discussions on cloud computing security in order to clear the ‘foggy cloud’ hovering over such a promising technology development. It seeks to inform and make decision makers aware of the real pertinent and justified security issues within coud computing."

Title: 188: User Customisation of Service Request Routing for the IP Multimedia Subsystem Authors: Richard Spiers (University of Cape Town) and Neco Ventura (University of Cape Town)

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Abstract: "The IP Multimedia Subsystem (IMS) is a framework standardised by the 3rd Generation Partnership Project (3GPP) to provide next generation multimedia services. The control protocol used in the IMS is the Session Initialisation Protocol (SIP), and service creation entails the creation of a SIP Application Server (AS). The AS communicates with the the IMS framework through SIP messages. The IMS framework, most notably the Serving Call Session Control Function (S-CSCF), determines which SIP messages to forward from the end user to which particular AS. These decisions are driven by the concept of Initial Filter Criteria (iFC). These filters contain a list of items to compare to the SIP message together with the AS to forward the message to if it matches. This list is statically configured by the network operator, and each filter is assigned a rank or priority. These priorities determine the order in which they are compared to the incoming request, and hence which AS actually gets triggered to provide the service first. The incoming request is then forwarded to the next matching AS once the first AS finishes its service execution, forming a chain of different AS. The purpose of this paper is to present a mechanism to allow the end user to control this message flow, and thereby allow them control over how their services get invoked. Several new entities are added to allow this functionality. These modifications allow the end user to customise their service usage, as well as providing offline conflict detection resolution."

Title: 194: A Grid Infrastructure for Knowledge-based applications in Open and Dynamic Computing

Environments Authors: Edgar Jembere (University of Zululand), Sibusiso. S. Xulu (University of Zululand) and Matthew. O. Adigun

(University of Zululand) Abstract: "The drive towards net-centric applications that enable ubiquitous computing has led to the need for computing

system to operate and interact at knowledge level. In order for this vision to be realised, knowledge need to be modelled as a resource that is made available to computing systems on a global scale. To address the is issue, we envisage a grid infrastructure that allows computing systems to interact at semantic level, and have the capabilities to share, learn and evolve knowledge representations. Some solutions that seek to achieve this goal have been proposed. These include techniques emanating from the semantic web, semantic grid and knowledge grid efforts. However, non among these solutions have specifically addressed how uncertainty that characterise such environments and evolution of the knowledge representations can be addressed. We propose a Grid Infrastructure for Open and Dynamic Knowledge-Based Applications (GIODKA), building upon probabilistic knowledge representation to handle uncertainty and Belief Change Analysis (BCA) techniques to handle evolution of knowledge representations. In this paper we discuss the design consideration and architecture of GIODKA. We also present the implementation details of the system. Finally, we discuss how the system can be used to support knowledge-based personalisation in SOA environments."

Title: 199: Architecting an SOA-based System for Sharing of Peripheral Network Resources Authors: Wandile Sibewu (University of Fort Hare) and Mamello Thinyane (University of Fort Hare) Abstract: "A number of new developments are being made in the Information and Communication Technology (ICT) field

and one of such is the adoption of Service Oriented Architecture (SOA), which not only allows humans to communicate with software services but also facilitates communication between different computing agents. At the same time ICT is increasingly being adopted as an enabler for economic development within Marginalized Rural Areas (MRAs) where resources are scarce and infrastructure is limited. The challenge of limited resources (e.g. peripheral devices) in MRAs can be addressed through the implementation of services that enable the sharing of such limited resources. This paper describes the research that has been done in developing Web Service wrappers for standard computing peripheral devices such as scanners, fax machines, and printers. The service is developed for use in MRAs, but can also work for Small Medium Enterprises (SMEs) or any environment that requires the convenience offered by the service. The paper will go on to discuss the architecture and the implementation details of the service."

Title: 202: Developing a Cross Platform IMS Client using the JAIN SIP Applet Phone Authors: Walter Tawanda Muswera (Rhodes University) and Alfredo Terzoli (Rhodes University) Abstract: "The interest in the adoption of the IP Multimedia Subsystem (IMS) by industry and research institutes has

resulted in the establishment of IMS testbeds for developing and deploying IMS services. The client applications used for testing and consuming services within these testbeds are important for the overall success of the developed services. Currently, there is no single free client that provides researchers with all the required functionality needed to test their applications. For example, several open and closed source IMS clients are used within the Rhodes University Convergence Research Group (RUCRG) in order to utilise specific features to test developed applications. In this paper we present an overview of three popular IMS clients currently in use within the RUCRG. We then discuss the features and the design architecture of the JSAP (JAIN SIP Applet Phone) which is used as the foundation for developing a new IMS compliant client. An analysis is then given regarding the functionality that JSAP lacks, features that have been added and the results of the various compatibility tests that have been performed between the new IMS client, SIP (Session Initiation Protocol) application servers and other freely available IMS clients. Finally, we discuss the features that are still to be added to the new client."

Title: 210: Composing a Simple Friend-finder Application Using the SIP Location-based Services Toolkit Authors: Shange Ndakunda (Rhodes University), Madeleine Wright (Rhodes University) and Alfredo Terzoli (Rhodes

University) Abstract: "The increase of data traffic and access to the Internet has resulted in more consumer-driven markets. There is

increasing pressure for Mobile Network Operators (MNOs) to quickly and innovatively provide personalised multimedia services that combine voice, video, presence and location. Many traditional SIP applications have always included presence capabilities in their implementations. Location, on the other hand has been less popular, possibly due to the lack of relevant software and hardware as well as the cost-effectiveness of delivering such services. Recent trends have indicated that Location Based Services(LBS) adoption and development are on the increase. The main focus of this paper is to showcase the functionality of a SIP Location Based Services (LBS) toolkit and location-aware Mobicents Presence Service we put together. This is

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done through the development of a basic friend finder service. More cross-referencing LBS applications can be developed quickly using our toolkit."

Network Engineering Title: 113: Cooperative Sensing Reliability Improvement for Primary Radio Signal Detection in Cognitive

Radio Environment Authors: Jide Julius Popoola (University of the Witwatersrand) and Rex van Olst (University of the Witwatersrand) Abstract: "In this paper, we propose an efficient sensing time algorithm for predicting ideal sensing duration for detecting

a primary radio signal in a cognitive radio environment. The algorithm was developed using a computational model in the MATLAB environment. We use the algorithm to fashion how cooperative gain can be improved without incurring a cooperative overhead. The simulation results show that cooperative sensing can work effectively without incurring a cooperative overhead if sensing time parameters are perfectly selected. The result of the study also reveals the effectiveness of cooperative sensing over non-cooperative sensing in a cognitive radio environment. The obtained sensing duration from our developed algorithm falls in the millisecond range, which is ideal for preventing interference to and from a primary radio signal."

Title: 119: Rate Adaptation in Ad Hoc Networks Based on Pricing Authors: Fredrick Awuor (Tshwane University of Technology), Karim Djouani (Tshwane University of Technology),

Guillaume Noel (Tshwane University of Technology) and Thomas Olwal (CSIR Meraka Institute) Abstract: "Nodes in ad hoc networks are autonomous and self-configuring with no form of centralized administration

such that nodes are free to selfishly optimize their individual utilities without considering utilities of other network users. This compels users to transmit at high power leading to abnormal interference in the network hence degrades network performance (i.e. low data rates, loss of connectivity among others). In this paper, we propose rate adaptation based on pricing (RAP) algorithm that incorporates penalty (pricing) obtruded to users' choices of transmission parameters to curb the self-interest behaviour. Therefore users determine their data rates and transmit power based on the perceived coupled interference at the intended receiver and the network cost charged by other network users. The proposed rate adaptation RAP is formulated as a network utility maximization (NUM) problem based on coupled interference minimization and solved using reverse engineering satisfying Karush-Kuhn-Tucker (KKT) conditions. The simulation results show that the proposed algorithm improves network performance compared to the legacy 802.11 standard."

Title: 120: SBYaoGG: Distributed Energy Efficient Topology Control with Low Interference Authors: Tapiwa Chiwewe (University of Pretoria) and Gerhard Hancke (University of Pretoria) Abstract: "Topology control plays an important role in the design of wireless ad hoc and sensor networks; it is capable of

constructing networks that have desirable characteristics such as sparser connectivity, lower transmission power and a smaller node degree. In this research a novel distributed topology control technique called the novel Smart Boundary Yao Gabriel Graph (SBYaoGG) is presented that enhances energy efficiency and reduces radio interference in wireless sensor networks. Each node in the network makes local decisions about its transmission power and the culmination of these local decisions produces a network topology that preserves global connectivity. Results of simulations are presented demonstrating the effectiveness of this new technique as compared to other approaches to topology control."

Title: 141: The implementation of LT network coding in resource limited RLNC networks Authors: Sune von Solms (North-West University) and Albert S. J. Helberg (North-West University) Abstract: "We introduce an improved coding method constructed through the combination of the low complexity aspects

of both random linear network coding (RLNC) and Luby Transform (LT) codes. The introduced method can successfully transmit data over a network while saving network resources. When compared to the implementation of LT network coding, the proposed method consumes fewer network resources."

Title: 145: Effects of Variations in Structural Parameters on Performance of Switched Parasitic Arrays Authors: Mofolo R.O. Mofolo (CSIR Meraka Institute), Albert A. Lysko (CSIR Meraka Institute), Willem A. Clarke (CSIR

Meraka Institute) and Thomas O. Olwal (University of Johannesburg) Abstract: "Influences of variations in the structural parameters (or antenna dimensions) of the five elements circular

switched parasitic array (SPA) antenna at 2.4 GHz are investigated in this paper. Variations in the structural parameters are assumed to model random errors in such parameters. The effects of these variations on the performance of the SPA antenna are investigated using a numerical approach. Mutual coupling between the array elements is taken into consideration. The variations are modelled assuming both uniform and Gaussian distributions, and they are simulated using MATLAB. The simulation results demonstrated that variations in each structural parameter can either increase or decrease the SPA antenna gain and input impedance depending on the given specifications. The gain and input impedance sensitivities per unit variation in each structural parameter are computed to determine the level at which the gain and input impedance can vary for a small predefined change (or error) in the structural parameter."

Title: 166: Operation and Performance of Cognitive Radios in Vehicular Environments Authors: Eugenia Rudo Nyanhete (French South African Institute of Technology), Mjumo Mzyece (Tshwane University

of Technology) and Karim Djouani (Tshwane University of Technology) Abstract: "In this paper, we look at the application of cognitive radio technology in vehicular networks. We explore some

of the negative impacts of the vehicular environment on the operation of cognitive radios. These include a cognitive radio operating as a secondary (unlicensed) user not detecting a primary (licensed) user and thus causing interference to that user. We also look at how cognitive radios can choose a modulation technique based on the system signal to interference plus noise ratio (SINR). Lastly, we discuss how these findings can

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help us to apply cognitive radio technology to the vehicular environment." Title: 173: Enhanced Distributed Mobility Management Schemes for NGWNs Authors: Petro P. Ernest (University of Cape Town), Olabisi E. Falowo (University of Cape Town), H. Anthony Chan

(University of Cape Town) Abstract: "The IETF IP working group is working on the solutions to address the deployment of current IP mobility

management in a distributed and dynamic mobility management approach. The work is aimed at addressing the limitations that arise when the current IP mobility management schemes are used, considering the increasing data traffic volume and trends in evolution of mobile network toward flattened architecture. Various solutions have been proposed to address those limitations. However, most of the proposed solutions still experience long route for long lasting traffic, handover latency, and packet loss. In order to address these issues experienced in the existing solutions, we propose two schemes. Furthermore, we describe the design approach and the operation of the schemes."

Title: 183: Comparison of Routing Metrics for Wireless Mesh Networks Authors: Siphamandla Nxumalo (University of Zululand), Matthew Adigun (University of Zululand), Pragasen Mudali

(University of Zululand), Ntsibane Ntlatlapa (University of Zululand) and Sakhile Ncanana (CSIR Meraka Institute)

Abstract: "Abstract-A number of routing metrics exist in wireless networks. These routing metrics were originally designed for mobile ad hoc networks (MANETs). When Wireless Mesh Networks (WMNs) came into being, an idea of introducing and using these routing metrics for WMNs was considered. The problem that arises is that these routing metrics have not been proven whether they work best in WMNs. These routing metrics have to be compared before they can be used in WMNs, so as to choose the best routing metric for WMNs among existing routing metrics before designing new one. There are works in the literature that compare the routing metrics, but the comparisons are not done a consistent manner. The main aim of this paper is to compare the routing metrics in a consistent manner. This paper simulates four routing metrics in NS2, with Ad hoc On Demand Vector (AODV) protocol as a routing protocol. After the routing metrics have been simulated, the results of the simulation are compared to see which routing metric performed best. From the evaluation, design criteria for an ideal routing metric for WMNs are recommended."

Title: 187: Downlink Packet Scheduling for Variable Bitrate Traffic in LTE Networks Authors: Joel Makara (University of Cape Town) and Neco Ventura (University of Cape Town) Abstract: "In recent years, there has been a sharp increase in the demand for real-time multimedia applications from

mobile subscribers. Voice and video are the most common forms of network traffic used in these applications and to optimise space-quality ratios, variable bitrate coding techniques are used to encode them. Even with the advent of high speed access network technologies such as the long term evolution (LTE), there is a need for efficient management of radio resources to ensure that the quality of service (QoS) requirements for these applications is met. We present an optimised scheduling approach that exploits multiuser diversity by considering each user’s instantaneous downlink conditions and QoS information when distributing resources. Simulation results show that our proposed scheme outperforms other dynamic resource allocation approaches with regards guaranteeing quality of service and overall system throughput."

Title: 193: Evaluation of Transport Layer Protocols over Wireless Multi-hop Networks Authors: Sakhile Nanana (University of Zululand), Pragasen Mudali (University of Zululand), Siphamandla Nxumalo

(University of Zululand), Bethel Mutanga (University of Zululand) and Matthew Adigun (University of Zululand) Abstract: "Abstract- In wireless multi-hop network (WMN), numerous QoS mechanisms such as routing, topology control

protocol and transport layer protocols (TLPs) have been proposed. The focus of this study is on the TLPs. TLPs are responsible for connection establishment and attempt to ensure that all data are transmitted from source to target destination safely. Performance of Traditional TLP (such as TCP) deteriorates in WMNs. Traditional TLPs assume that all packets losses are due to network congestion, whereas the WMN can be greatly affected by other causes such link and route failure, route changes, and medium contention in a shared environment with an increasing network size. Several TLPs have been proposed to address this problem in the literature, but it is not clear which of these TLPs provide optimal performance over WMNs, since they are not compared in a consistent manner in previous works. As a result, we selected ten representative samples from TLPs present in literature. Using ns2 simulator, we evaluated and compared the performance of the selected TLPs. Based on the results obtained, recommendation on the design features for an ideal TLPs applicable to WMNs were made."

Network Management & OSS Title: 129: A Highly Scalable Monitoring Tool for WiFi Networks Authors: Pheeha Machaka (University of Cape Town), Antoine Bagula (University of Cape Town) and Nico De Wet

(RedButton Mobile CC) Abstract: "The paper introduces a monitoring tool that was designed for a existing network of Wi-Fi hotspots. This was

done by adding monitoring and visualization components to the existing network. It was found out that the monitoring tool was more scalable and effective than traditional monitoring tools."

Title: 142: A Real-Time Charging Platform for Converged Multimedia Services Authors: Joyce B. Mwangama (University of Cape Town) and Neco Ventura (University of Cape Town) Abstract: "Network operators can achieve rapid service proliferation by exposing their networks to external content and

service providers. They would create interfaces that would allow these service and content providers to offer their applications and services to users. Composing and bundling of these services will essentially create new

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services for the user and achieve rapid deployment of enhanced services. The concept of offering a wide range of services that are coordinated in such a way that they deliver a unique experience has sparked interest and numerous research on Service Delivery Platforms (SDPs). Issues relating to settlement of service usage charges in this distributed environment need to be carefully considered. The effectiveness of a real-time charging system for these multi-domain composite services is dependent the charging procedures of the Online Charging System which impacts on the overall management system efficiency. In this paper the design and implementation of a real-time charging system for converged multimedia services is presented."

Title: 149: An Evaluation of Trading Bands as Indicators for Network Telescope Datasets Authors: Bradley Cowie (Rhodes University) and Barry Irwin (Rhodes University) Abstract: "Large scale viral outbreaks such as Conficker, the Code Red worm and the Witty worm illustrate the

importance of monitoring malevolent activity on the Internet. Careful monitoring of anomalous traffic allows organizations to react appropriately and in a timely fashion to minimize economic damage. Network telescopes, a type of Internet monitor, provide analysts with a way of decoupling anomalous traffic from legitimate traffic. Early warning of possible incidents can be provided by observing the fluctuations in network telescope datasets. Data from network telescopes is used by analysts to identify potential incidents by comparing recent trends with historical data. Analysis of network telescope datasets is complicated by the large quantity of data present, the number of subdivisions within the data and the uncertainty associated with received traffic. While there is considerable work being performed in the field of network telescopes little of it is concerned with the analysis of alternative methods of incident identification. This paper considers trading bands, a subfield of technical analysis, as an approach to identifying potential Internet incidents such as worms. Trading bands construct boundaries that are used for measuring when certain quantities are high or low relative to recent values. This paper considers Bollinger Bands and associated Bollinger Indicators, Price Channels and Keltner Channels. These techniques are evaluated as indicators of malevolent activity by considering how these techniques react to incidents identified in the captured data from a network telescope."

Network Planning and Optimization Title: 107: Rain Cell Size Statistics from Rain Gauge Data for Site Diversity Planning and Attenuation

Prediction Authors: Peter Akuon (University of KwaZulu-Natal) and Thomas Afullo (University of KwaZulu-Natal) Abstract: "Cell size statistics for the rainfall types in Durban, South Africa have been derived from a five-year, one-hour

integration time series rain gauge network data. The data have been converted to their equivalent one-minute integration time values and processed to determine the cell sizes for different rain rate above threshold values between 3 mm/h and 20 mm/h. The results are then compared to the cell size statistics from one-minute integration time data from disdrometer measurements taken for two years. By the use of the terrestrial link attenuation data obtained for Durban, the advection velocity for the stratiform rain has been derived as 6 m/s. The separation distance between diversity sites in the Durban area has been proposed as well as the equivalent rainfall cell diameter distribution model which is an input requirement in the proposed rain attenuation prediction equation."

Title: 108: Estimation of Parameters for Lognormal Rainfall DSD Model for Various Rainfall Types in Durban Authors: Akintunde Alonge (University of KwaZulu-Natal) and Thomas Afullo (University of KwaZulu-Natal) Abstract: "Cell size statistics for the rainfall types in Durban, South Africa have been derived from a five-year, one-hour

integration time series rain gauge network data. The data have been converted to their equivalent one-minute integration time values and processed to determine the cell sizes for different rain rate above threshold values between 3 mm/h and 20 mm/h. The results are then compared to the cell size statistics from one-minute integration time data from disdrometer measurements taken for two years. By the use of the terrestrial link attenuation data obtained for Durban, the advection velocity for the stratiform rain has been derived as 6 m/s. The separation distance between diversity sites in the Durban area has been proposed as well as the equivalent rainfall cell diameter distribution model which is an input requirement in the proposed rain attenuation prediction equation."

Title: 128: The Effect of Network Coding on the Network Throughput of Wireless Mesh Networks Authors: Corna Wierenga (North-west University) and Leenta M.J. Grobler (North-west University) Abstract: "Wireless Mesh Networks (WMNs) are communication networks where users, routers, APs and any other

device with networking capabilities forge a wireless ad hoc network amongst themselves. This offers many advantages such as a decrease in network set-up costs, increased network coverage, access opportunities to external networks (previously not possible without the right equipment) and even access to different network types such as sensor networks, cellular networks, computer networks, wired networks etc.. It also implicates several concerns or issues regarding to security, network management, and ever present scalability issues. Since the wireless nodes in a WMN broadcast their data by nature, there will always be redundant traffic present in data transmissions. Network coding offers a way to improve on the network performance, by sharing network resources while at the same time keeping information separate. This paper study the effect of network coding on the aggregated throughput in WMNs by means of an optimisation model."

Title: 130: An Optimization approach for Capacity Enhancement in 3G Mobile Networks Authors: Raymond Juma (French South African Institute of Technology), Karim Djouani (Tshwane University of

Technology) and Anish Kurien (Tshwane University of Technology) Abstract: "In this paper a mathematical programming approach that makes use of Tabu search of the optimization

process is proposed to solve the problem of reduced quality of service due to increased number of users(increased capacity ) in the network that existing infrastructure cannot support. The approach takes into

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consideration site selection as an integer problem and site placement as continuous problem and addresses them in parallel in finding the optimal placement of node Bs in the existing network so as to solve the problem of increased number of users and hence improving on the quality of service. It will also minimize the number additional sites required and hence the reduction in the overall cost of the network. The newly selected sites that were not originally considered during the initial installation set up are taken into consideration. This approach considers all users at all potential sites and gives direction on the placement of node Bs in line with the users’ distribution. Node Bs are classified as critical or un-critical depending on their effect in the network when eliminated. Tabu search operates on the un-critical list through the process of drop move and re-assignment of users until a critical stage is reached when further elimination causes coverage and capacity problems. The proposed approach is shown to bring out an improved quality of service and a 24% site location reduction of node Bs in the network."

Title: 144: Modeling a Link Level Simulator for Long Term Evolution Uplink Authors: Armando Ubisse (University of Cape Town) and Neco Ventura (University of Cape Town) Abstract: "The 3GPP standardized LTE and has chosen OFDMA and SC-FDMA as access technologies for the downlink

and uplink respectively due their high spectral efficiency. A big part of this efficiency will rely on channel dependent scheduling (CDS), which reacts to environmental conditions. In order to study CDS and other adaptation techniques like interference management, simulations need to be performed. However, simulating a whole network system is computationally expensive, so to avoid this System level simulators are used. In order to create a system level simulator, link level simulations must be performed first. This paper describes the implementation of such a link level simulator in MATLAB for LTE uplink based on an open source model."

Title: 205: Engineering Reconfigurable Mobile Network Agents Based on Resource Coordination Authors: Stanley Ogbeide (University of Cape Town) and Alexandru Murgu (University of Cape Town) Abstract: "An inherent characteristic of future wireless networks will be their heterogeneity, manifested by the present of

different access network with great variety of mobile terminal capabilities. While this integration of multiple wireless access networks can potentially provide extended coverage and additional value added services to mobile terminal users, it may often lead to instability of the underlying network topology. These network technologies are expected to exhibit different infrastructure capabilities in terms of coverage, capacity, transmission rates, transmission delay, and transmission cost which mandated network providers to either be cooperative or in a competitive relationship for resources. Coordinating resources in such multi-network platform is far from straight forward. In this respect, we provide an autonomous scheme based on Reconfigurable Mobile Network Agents (RMNA) to optimize resource management in advance. This describes an interaction model that support network-wide resource coordination in two different approaches; i) Resource pooling for realizing cooperative communication transaction, ii) Resource splitting for implementing diversity communication and enabling reliability enhancement."

Network Services Title: 109: Long Term Evolution Technology-Rural Wireless Architecture Model (LTE-RWAM): Enhances

Mobile Connectivity in Remote Areas Authors: Jameson Mbale (University of Namibia) and Victor Hamutenya (Telecom Namibia) Abstract: "The Long Term Evolution-Rural Wireless Architecture Model (LTE-RWAM) is a multiple of demarcated

telecommunication cells each composed of a series of eNodeB’s, MIMO structures, Access Gateway’s (AGW) and connected at source and end to the Evolved Packet Cores (EPC). The EPC is connected to the communication cells through the eNodeB Interface (X2) and Core Network Interface (S1) and is built to support packet-switched traffic. EPCs are connected to eNodeBs that are enhanced base stations that provide air interface and perform radio resource management for the access systems, radio balancing and radio mobility control including handover decisions for mobile user equipment (UE). Within the eNodeB’s are MIMO structures employed to use multiple transmitters to send data from the source to the recipient. In fact, the whole system uses affordable but complex equipment that is capable of carrying signals over long distances. The LTE-RWAM enhances mobile connectivity in remote populated regions. The LTE-RWAM system is constructed across the rural sectors to ensure mobile network connectivity. Such a wireless architecture was designed to provide effective connectivity to rural sectors providing mobile services at a low costs as the infrastructure needs to cover a wider geographical areas."

Title: 136: Improving the performance of an automatic speech recognizer with domain-specific syntax

structures. Authors: Moyahabo Rapholo (University of Limpopo), MJD Manamela (University of Limpopo) and Dr N Gasela

(University of Limpopo) Abstract: "Automatic Speech Recognition (ASR) is a technology that allows a computer to identify spoken words and

translate those spoken words into text. Speech recognition systems have started to be used in many application areas such as healthcare, automobile, e-commerce, military, and others. The use of these speech recognition systems is usually limited by their poor performance. In this research work, we are looking at improving the performance of the baseline ASR systems by incorporating domain-specific syntactic structures in grammar into an existing Northern Sotho ASR system, based on hidden Markov models (HMMs). The syntactic structures will be applied to the vocabulary used within the domain of a healthcare application area. We use the Backus-Naur Form (BNF) and the Extended Backus-Naur Form (EBNF) to specify the grammar. The experimental recognition results obtained using Hidden Markov Model Toolkit (HTK) show the overall improvement to the baseline ASR System."

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Title: 143: Creating an Automated Grid Repair System Authors: Leslie Luyt (Rhodes University) and Karen Bradshaw (Rhodes University) Abstract: "With the rise in interest in the field of Grid and Cloud computing, it is becoming increasingly necessary for the

Grid to be easily maintainable. This maintenance of the Grid and Grid services can be made easier by using an automated system to monitor and repair the Grid as necessary. We propose such a system to perform automated monitoring and repair. Preliminary results show that certain faults can be easily detected and repaired."

Title: 154: Underwater Wireless Sensor Network Localisation for Worhmhole Attack Detection Authors: Victor Obado (French South African Institute of Technology), Majid Hosseini (Tshwane University of

Technology), Karim Djouani (Tshwane University of Technology) and Guillaume Noel (Tshwane University of Technology)

Abstract: "Abstract- In this paper, a localisation based technique is proposed to detect the wormhole attack in underwater wireless sensor networks (UWSNs). Our localisation technique utilises the Lambert W function and received signal strength (RSS) between sensor nodes to measure accurate distances between these nodes. Thereafter, the localisation proceeds through multilateration and a further refinement process to attain accurate node positioning. This is a two-level hybrid computation approach that allows the nodes to attain a coarse estimation of their positions in a distributed manner while the sink, which has more resources, calculates accurate positions in a centralised manner. The accuracy is important to avoid introducing false alarms during detection which will proceed by utilising the nodes positions as well as the distance and connectivity with their neighbors."

Title: 176: Creating a Pronunciation Dictionary for Automatic Speech Recognition-a Morphological approach Authors: Mpho Caselinah Nkosi (University of Limpopo), MJD Manamela (University of Limpopo) and N Gasela

(University of Limpopo) Abstract: "The Pronunciation dictionaries or lexicons play an important role in guiding the predictive powers of the

Automatic Speech Recognition (ASR). As the use of automatic speech recognition systems increases, there is a need for the development of dictionaries that cover a large number of inflected word forms to enhance the performance of ASR systems. This paper describes the morphological-driven approach to the creation of a more comprehensive and broadly representative Northern Sotho pronunciation dictionary for ASR systems to augment the existing data-driven methods of dictionary creation. The Preliminary results of an ASR system using morphologically–based rules for a dictionary creation are discussed."

Title: 179: A Mobile Diary Application for Diabetes Management in South Africa Authors: Hanh Le (University of Cape Town), Altus van der Merwe (University of Cape Town) and Mervyn Abrahams

(University of Cape Town) Abstract: "In this paper we propose a new algorithm, called Data Mule Intercommunication (DMI), that aims to increase

message delivery between isolated networks. A data mule is a combination between an electronic device and a mobile entity. Mules are used to deliver messages between networks that were disconnected originally. This paper proposes to cluster data mules in order to find a more reliable and faster path between the sender and the receiver. Instead of data remaining on the same mule when travelling from one network to another, our algorithm allows mules to transfer data to nearby mules arriving to the destination network sooner. A variation of our algorithm is a combination of clustering between data mules and the optimal relay path (ORP) algorithm. The ORP calculates the shortest path from one data mule to another."

Title: 182: A Text-to-Speech Synthesis System Using hidden Markov models for Xitsonga Authors: Ntsako Baloyi (University of Limpopo), MJD Manamela (University of Limpopo), N Gasela (University of

Limpopo) Abstract: "From several current spoken language processing research reports it has been shown that the development

of a text-to-speech synthesis system using the HTS toolkit based on hidden Markov models can be achieved without requiring a huge training speech corpus. Intelligible and natural sounding speech is therefore achievable. The quality of synthesized speech, however, does not equal that of recorded speech. Some speaker characteristics and speaking styles are modeled by trained hidden Markov models from context-dependent labels. Xitsonga is a resource-scarce language spoken in more than three Southern African countries. The speech synthesis system for Xitsonga based on hidden Markov model discussed in this paper focuses on Xitsonga language as it is spoken in the Republic of South Africa. The preliminary results obtained after training the text-to-speech synthesis system show that the developed system is intelligible and it also obtains some level of naturalness. The mean opinion score tests attain 92.3% of acceptability from first language speakers."

Title: 190: Integration of HTK Speech Recognizer with OpenVXI and Asterisk based VoiceXML Gateway Authors: Lerato Lerato (National University of Lesotho), Molise Mokhomo (National University of Lesotho), Thato

Pebane (National University of Lesotho) and Lerato Mohapi (National University of Lesotho) Abstract: "VoiceXML has become the central markup language used in commercial IVR systems today. It is still not

possible to find the fully functional open source VoiceXML gateway that helps researchers enhance the VoiceXML IVR technology. It is essential that a free and open source VoiceXML IVR platform that meets all the W3C standards is designed and made available so that the quality of IVR systems can be consistently improved at the justifiable cost. This paper introduces the VoiceXML gateway that comprises the integration of OpenVXI and Asterisk telephony platform focusing on the addition of the HTK-based speech recognition capability of the system. The finally paper reports the successful implementation of the recognition interface that conforms to the SRGS specification."

Title: 200: Towards a Toolkit for creating video-oriented services for Mobicents Authors: Zelalem Sintayehu Shibeshi (Rhodes University), Alfredo Terzoli (Rhodes University) and Karen Bradshaw

(Rhodes University)

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Abstract: "The research community seems to have settled on the selection of an IMS core testbed for testing IMS services. The “Open IMS Core” has been the de facto standard for IMS core by the academic research community for a long time. On the other hand, there is no one single service development platform that has become a de facto standard for multimedia service development for IMS. One important subset of video oriented services in the IMS environment is IPTV and there is no obvious choice for IPTV service development from the open source community. The IPTV specification lists the use of various protocols to implement an IPTV service. There are different options for implementing these protocols. For example, using the different platforms that implement these protocols and combining them to develop and implement IPTV services. This, however, has disadvantages such as lack of consistency and incompatibility with each other. A relatively recent open source service development environment, Mobicents, could solve these problems. Mobicents brings together implementation of different IPTV protocols, and provides a platform for service developers. Mobicents is still a complex framework and requires a steep learning curve ideally. Programmers who don't know about telecom protocols or the Mobicents programming model should be able to use its functionalities and develop video-oriented services easily. In this paper we discuss the design of a Toolkit to ease the development of video-oriented services in Mobicents"

Title: 209: Situation-aware Routing Based on Link Quality for Static Mesh Networks with Mobile Nodes Authors: Hlabishi Isaac Kobo (University of the Western Cape), William Tucker (University of the Western Cape) and

Xiaoming Liu (University of the Western Cape) Abstract: "The research community seems to have settled on the selection of an IMS core testbed for testing IMS

services. The “Open IMS Core” has been the de facto standard for IMS core by the academic research community for a long time. On the other hand, there is no one single service development platform that has become a de facto standard for multimedia service development for IMS. One important subset of video oriented services in the IMS environment is IPTV and there is no obvious choice for IPTV service development from the open source community. The IPTV specification lists the use of various protocols to implement an IPTV service. There are different options for implementing these protocols. For example, using the different platforms that implement these protocols and combining them to develop and implement IPTV services. This, however, has disadvantages such as lack of consistency and incompatibility with each other. A relatively recent open source service development environment, Mobicents, could solve these problems. Mobicents brings together implementation of different IPTV protocols, and provides a platform for service developers. Mobicents is still a complex framework and requires a steep learning curve ideally. Programmers who don't know about telecom protocols or the Mobicents programming model should be able to use its functionalities and develop video-oriented services easily. In this paper we discuss the design of a Toolkit to ease the development of video-oriented services in Mobicents"

Optical Transport and Core Networks Title: 147: Efficient burst assembly algorithm with traffic prediction Authors: Mmoloki Mangwala (North West University), Boyce B. Sigweni (North West University) and Bakhe M. Nleya

(North West University) Abstract: "In this paper we consider burst assembly algorithms and traffic prediction. The ultimate goal is to propose a

new burst assembly algorithm which is based on time-burst length (hybrid) threshold with traffic prediction. The main goal is to reduce burst assembly delay in Optical Burst Switching (OBS) networks"

Title: 163: Impact of PMD on distributed Raman amplifiers using modern transmission fibres Authors: Kennedy Muguro (Nelson Mandela Metropolitan University), Tim Gibbon (Nelson Mandela Metropolitan

University), David Waswa (Moi University, Kenya) and Andrew Leitch (Nelson Mandela Metropolitan University)

Abstract: "We experimentally and numerically investigate Raman amplification and polarization mode dispersion PMD effects on a channel using two fibres of PMD coefficients 0.01pskm-1/2 and 0.1pskm-1/2 respectively. Two pumping configurations were employed to evaluate the signal gain and OSNR over a range of wavelengths. Using the non-return to zero (NRZ) data format the quality of the signal was simulated. It is found that under the same conditions the fibre with lower PMD coefficient has superior performance in the forward pumping scheme."

Title: 169: Log domain Turbo STFC decoding with the Zero Forcing and MMSE Decoders Authors: Philip Rudolph Botha (University of Pretoria) and B.T. Maharaj (University of Pretoria) Abstract: "In this paper, a method for the joint decoding of a MIMO system using apriori information in conjunction with

the Zero-Forcing and Minimum Mean Squared Error decoders is presented. The proposed method is compared with an existing method based on receive vector translation. It is shown that both methods perform similarly in the case of the Zero-Forcing decoder. Unlike the method based on receive vector translation, which is shown to be limited to binary valued constellations,the proposed method can be used with an arbitrary signal constellation. The proposed method also has a reduced computational requirement."

Protocols Title: 112: The Effect of DAD timeout period on Address Auto-configuration in Wireless ad-hoc networks Authors: Murimo Bethel Mutanga (University of Zululand), Matthew Adigun (University of Zululand), Tarirai Chani-

Mutanga (MONASH University), Pragasen Mudali (University of Zululand) and Martin Mhlanga (University of

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Zululand) Abstract: "Wireless mesh networks have received a lot of attention as a means of connectivity in community and

commercial entities. The easy deployment and self management characteristics of WMN makes it a good choice for rural areas. However, in most African countries, electricity is scarce in rural areas. A candidate solution to the power problem is the use of solar/battery powered nodes. Using this approach, the solar panel charges’ the battery when there is sunlight and the nodes make use of the battery power at night or when there is no sunlight. Much work has been carried out in the optimization of network protocols to minimize power consumption. Different protocols at different layers have varying effects on the power consumption of the nodes. In this research work we present a battery-powered WMN (Wireless Mesh Networks) nodes performance comparison of the TCP, UDP, Video/Audio streaming and data files in terms of power consumption. We evaluate how different existing Quality of Service mechanisms affects the power consumption and network lifetime of solar/battery-powered WMN nodes. This research is motivated by the increasing use of WMN at the rural areas which have attracted considerable interest in recent years as a convenient, flexible and low-cost alternative to wired communication infrastructures in many contexts."

Title: 118: Improving Cooperation in Mobile Ad Hoc Networks Authors: Johannes Goebel (University of Hamburg) and Anthony Krzesinski (University of Stellenbosch) Abstract: "Consider a mobile ad hoc network (MANET) where packet transmissions occur between mobile nodes. The

nodes act as relays to form multi-hop routes connecting the origin-destination node pairs that are out of radio transmission range with respect to each other. If the nodes do not to belong the same authority, then a protocol must be deployed so that the nodes are given an incentive to spend their resources (battery power and bandwidth) in forwarding packets that originate at other nodes. This can be done by introducing a credit balance for each node, where the nodes use credits to pay for the costs of sending their own traffic, and earn credits by forwarding traffic from other nodes. This paper presents two schemes to promote collaboration in MANETs. In the first scheme, power consumption at each node is regulated by periodically allowing each node to compare the power consumed thus far to a target power consumption: if the power consumed exceeds the target, the node will decrease its transmission range, else the node will increase its transmission range. In the second scheme, the nodes belong to several competing authorities. The nodes can cooperate by forwarding packets that originate from nodes that belong to a competing ISP. We investigate what happens when nodes from competing authorities cooperate and when they do not cooperate. Initial simulation experiments indicate that the two schemes substantially improve the performance of the MANET and extend the lifetime of the network by reducing the power consumption at the nodes."

Title: 134: Formal Verification of Initial Network Entry in WiMAX Networks Authors: Beth Komu (French South African Institute of Technology), Mjumo Mzyece (Tshwane University of Technology)

and Karim Djouani (Tshwane University of Technology) Abstract: "Abstract- The Initial Network Entry procedure is the first stage in establishing a connection in an IEEE 802.16-

(WiMAX) network. The process involves the transmission of unencrypted management messages which constitutes a major security flaw. The Man-In-The-Middle (MITM) attack exploits this weakness in the network by eavesdropping, interception and fabrication of the management messages, resulting in a breach in the reliability of the entire network. In this paper, we analyse a modification of the Diffie-Hellman key exchange protocol proposed to mitigate the man-in-the-middle- attack in WiMAX by modelling the protocol in Promela. Verification is then performed by use of the Spin model checker with the concurrent interaction of an intruder process so as to prove or disprove the protocol’s validity."

Title: 152: A Proxy Approach to Control Interoperability on Ethernet AVB Networks Authors: Osedum P. Igumbor (Rhodes University) and Richard Foss (Rhodes University) Abstract: "Ethernet AVB guarantees the necessary quality of service required to transmit real-time media, such as

audio/video content. The IEEE 1722 protocol defines the messaging format for transmission of media content on an AVB network. With the efforts of the IEEE 1722 and IEEE 1722.1 working groups, there is a drive towards interoperability amongst devices that implement these protocols. However, control of professional AVB compliant devices remains a challenge. This paper describes a design and implementation that will allow for common control and interoperability between devices that conform to different control protocols, namely AES-X170 and OSC protocols."

Title: 160: Modified Dynamic Source Routing for Wireless Sensor Networks: End-to-End Delay Analysis Authors: Chabalala S. Chabalala (University of KwaZulu-Natal), Thippeswamy N. Muddenahalli (University of KwaZulu-

Natal) and Fambirai Takawira (University of KwaZulu-Natal) Abstract: "Routing presents a significant design challenge to meet various application requirements in wireless sensor

networks (WSNs) communication. In this paper, we propose a minimum-delay multipath routing protocol with modification to dynamic source routing (DSR) protocol, which aims to minimize end-to-end delay to provide quality of service (QoS) support for delay-sensitive applications in WSNs. The proposed work takes into account, end-to-end delay and unreliability of wireless channel links to derive a routing metric used by the routing protocol to determine the cost associated with individual routes. Each node records multiple disjoint routes to the same destination, in which primary route selection is based on the derived routing metric to give preference to a route with minimum end-to-end delay for packet transmissions. Simulation results reveal better performance for the modified DSR protocol, most importantly when used for routing in unreliable wireless channel link conditions with high packet error rates."

Title: 212: Mobile Vertical Handover between Wireless LAN and Wireless Mesh Network Authors: Zimani Chitedze (University of the Western Cape) and William Tucker (University of the Western Cape) Abstract: "This paper addresses mobility management issues in an environment with both wireless LAN and wireless

mesh networks. We first examine wireless mesh network client side transparency within mesh mobility management protocols and then look at standard mobility management protocols. The client side transparency scheme enables mobile nodes to support mobility in heterogeneous and homogeneous networks. However,

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they are not necessarily compatible with mobile IP protocols. Although a typical mesh topology tends to be an unplanned graph and routes change dynamically, standard mobility management protocols such as MIPv6, HMIPv6, and FMIPv6 may be used for mobility management in wireless mesh networks. To learn how MIPv6 operates, we used the OPNET 16.0 MIPv6 model to simulate a heterogeneous wireless environment comprising both WLAN and WMN. The simulation results show that MIPv6 is able to manage vertical handover between WLAN and WMN. However, in our opinion, its performance with both route optimization and tunneled traffic mechanisms is not effective enough. MIPv6 suffers from handover latency and packet loss which can combine to compromise delay-sensitive applications such as video conferencing."

Software

Title: 122: Optimization of 4x4 Integer DCT in H.264/AVC Encoder Authors: Charles Smart Lubobya (University of Cape Town), Mqele .E Dlodlo (University of Cape Town), Gerhard de

Jagar (University of Cape Town) and Keith L Ferguson (CSIR Meraka Institute) Abstract: "Abstract- This paper gives the computation time speed-up improvements obtained for the forward and inverse

4x4 integer Discrete Cosine Transforms (DCT) in H.264/AVC video encoders at constant Peak Signal to Noise Ratio (PSNR). The H.264/AVC specifies use of Integer DCT transforms for decomposing the video signal from the spatial domain to the frequency domain. We implemented the integer DCT using the two- dimension (2-D) matrix multiplications and optimized our implementation using the one-dimension (1-D) butterfly methods in software. All conditions being equal, results show that the two 1-D methods outperforms the 2-D method by an average computation time speed-up of 1.7x to 1.9x. At these speed-ups our optimized implementation can be used in real-time video broadcasting/internet applications and in low bandwidth environment. Index Terms— H.264/AVC, Integer DCT, Computation time and SIMD instructions."

Title: 123: An Architecture to Support Multi-Touch Collaborative Information Retrieval Authors: Ivan Sams (Nelson Mandela Metropolitan University), Janet Wesson (Nelson Mandela Metropolitan University)

and Dieter Vogts (Nelson Mandela Metropolitan University) Abstract: "Collaborative Information Retrieval (CIR) is the process by which people working together can collaboratively

search for, share and navigate through information. Computer support for CIR currently makes use of single-user systems. CIR systems could benefit from the use of multi-user interaction to enable more than one person to collaborate using the same data sources, at the same time and in the same place. Multi-touch interaction has provided the ability for multiple users to interact simultaneously with a multi-touch surface. This paper presents a generalised architecture for multi-touch CIR applications. There are three main goals of the proposed architecture: to create hardware independence, to separate the gesture recognition and CIR information objects from the application code and to make use of an extensible gesture definition set to allow for application-specific operations. A prototype implementing this architecture is described which will be used to investigate the potential for multi-touch interaction techniques to effectively support CIR."

Title: 124: Software design for informal setups: Centring the benefits Authors: Christopher Chepken (University of Cape Town), Edwin Blake (University of Cape Town) and Gary Marsden

(University of Cape Town) Abstract: "Appropriating technology for the benefit of the very poor is a key theme of Information and Communication

Technology for Development (ICT4D). Our aim is to design systems that reduce the challenges faced by the poor in the informal sector of the labour market. However, designing for non-structured problem areas involving socio-economic webs is challenging and requires more than just the ‘normal’ user requirements gathering techniques. In such social problem areas solutions must prioritize the direct benefits for the target groups. In this paper, a novel design technique for designing in an informal sector problem areas, the case of day labour market, is presented. It involves iteratively reviewing field work results of a long term study, reinforcing those findings with existing literature and eventually critically validating the requirements using existing Management Information Systems (MISs). In this method, benefits to target users are placed at the centre throughout the design process. Our design outcome and its relation to the design process is also presented."

Title: 139: A Simulation Framework for Evaluating the Behaviour of a Modular Automated Main Distribution

Frame using OMNeT++ Authors: Marthinus Ignatius Botha (University of Pretoria) and Hans Grobler (University of Pretoria) Abstract: "Automated main distribution frames (AMDFs) are employed in telephone exchanges or central offices to

provide automated connectivity between subscriber loops and central office equipment. The major drawbacks of current implementations however are cost and reliability. A simulation model for evaluating the behaviour of various configurations of a modular AMDF implementations is presented. The model introduces permanent equipment card redundancies and allows client profiles to be created in order for researchers and designers to explore typical scenarios. Various statistics are recorded throughout the simulation which allows easy comparison of multiple simulation run results. The model can be used to evaluate and determine the optimal modular AMDF design for various design constraints."

Title: 170: SerViz: A Tool for Interactive Visualization of Web Service Collections Authors: Simone Beets (Nelson Mandela Metropolitan University) and Janet Wesson (Nelson Mandela Metropolitan

University) Abstract: "Existing web service discovery techniques require the user to explore large web service collections to find

specific web services. Thus, these techniques do not support the user in effectively discovering web services. Information visualization is proposed to overcome this problem but has not been widely applied to visualize web service collections. This paper introduces SerViz, an interactive prototype tool that is used to visualize

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web service collections using a network information visualization technique to aid web service discovery and selection. This paper will outline the proposed requirements of information visualization for web service discovery and discuss how these requirements are supported by SerViz. The design and implementation of SerViz is discussed as well as future work to be completed on this prototype."

Title: 177: LTSP DNS Round Robin Clusters: Green Technology Access Enablers for Telecommunication

Services in Marginalised Communities Authors: Ingrid Sieborger (Rhodes University), Alfredo Terzoli (Rhodes University) and Cheryl Hodgkinson-Williams

(University of Cape Town) Abstract: "Abstract--- Rural development is seen as a priority in South Africa; information and knowledge are key

strategic resources for social and economic development. Information Communication Technologies (ICTs) are seen as important tools in rural development, assisting in enabling change through economic development. In rural areas where ICT infrastructure is being expanded and deployed there is a need to provide appropriate technologies that support sustainability and meet the needs of the local community. In this paper we argue that the use of Linux Terminal Server Project (LTSP) cluster servers are appropriate technologies for use in computer laboratory environments for relatively inexpensive access to technologies by schools and local communities in rural areas. Typically LTSP clusters are deployed when there is a need to support 100s or 1000s of computers, however, we argue that by reusing recycled (older) desktop or server computers as cluster servers could lower the entry level costs of LTSP computing while maximising the use of available resources. The paper details the configuration of a Domain Name System (DNS) round robin cluster solution together with initial testing and results. It is suggested that LTSP cluster solutions, and the DNS round robin implementation, show promise for use in providing access technologies to rural communities and schools."

Title: 180: SHOP-Net: Moving from Paper to Mobile Authors: Michael J Talbot (University of Cape Town) and Gary Marsden (University of Cape Town) Abstract: "This paper describes the SHOP-Net system, a mobile handset-based stock ordering system. SHOP-Net

replaces a paper-based system with a digital screen-based system. We present how it was developed and evaluated using a user-centered design methodology with associated Human Computer Interaction (HCI) methods, in conjunction with a Nongovernmental Organization (NGO) that works with micro-enterprises. The importance of engaging both users and managers in design and evaluation is highlighted. A short pilot study has been conducted. Despite early teething challenges regarding the management of information made available to the server, the system seems promising and easy to learn. Furthermore, the various stakeholders at the NGO are enthusiastic for it to be put into full use."

Title: 181: The Study and Implementation of Shazam’s Audio Fingerprinting Algorithm for Advertisement

Identification Authors: Heinrich A. van Nieuwenhuizen (North-West University), Willim C. Venter (North-West University) and Leenta

M.J. Grobler (North-West University) Abstract: "The recognition of a person by his/her fingerprint is not a new concept, but the recognition of a piece of audio

by its audio sample, also known as its audio fingerprint, is. Different research groups have delivered different working implementations of audio fingerprinting for music, but not for advertisement identification. A fair judgment can therefore not be made whether the available algorithms is suitable for advertisement identification. In this paper, the audio fingerprinting algorithm of Avery Wang’s is implemented and studied in terms of accuracy, speed, versatility and scalability"

Title: 184: Hand Shape Recognition and Estimation for South African Sign Language Authors: Pei Li (University of the Western Cape), Mehrdad Ghaziasgar (University of the Western Cape) and James

Connan (Rhodes University) Abstract: "In this paper we present a novel system which recognises sign language hand shapes from video data

captured in 2D. By mapping the recognised hand shape from 2D to 3D, it is possible to obtain 3D co-ordinates of each of the joints within the hand using the kinematics embedded in a 3D avatar hand and smooth the transformation in 3D space between any given hand shapes. The novelty in our system is that it does not require a hand pose to be recognised at every frame, but rather that hand shapes be detected at a given step size. This architecture allows for a more efficient system with better accuracy than other related systems."

Title: 211: Stationary region predictor using a stationary camera Authors: Brett de Villiers (University of Johannesburg), Yuko Roodt (University of Johannesburg), Hans Roos (University

of Johannesburg) and Willem Clarke (University of Johannesburg) Abstract: "A method to determine the stationery probability of regions or feature points in a video sequence is proposed

in this paper. This is done by identifying feature points using the Harris corner detector, finding descriptors for the feature points and then tracking the feature points. The information gained from tracking the feature points is then used to determine the stationery probability of these features. This method is shown to successfully identify probable stationery and moving regions in video sequences."

Standardisation Initiatives, Innovation & Regulatory Title: 114: Performance Evaluation of Handover from UMTS to LTE using Voice Call Continuity Authors: Joyce Namakoye (University of the Witwatersrand) and Rex Van Olst (University of the Witwatersrand) Abstract: "In this paper, we evaluated the performance of voice handover from Universal Mobile Telecommunications

System (UMTS) to Long Term Evolution (LTE) using the Voice Call Continuity (VCC) procedure. The VCC handover was modelled on handover signal flows and the analysis was done using mathematical models for each of the partial procedures that made up the total interruption. Mathematical equations were written for the

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service interruption time within the VCC handover signal flows. The service interruption equation along with its mathematical models was simulated and results were obtained. The results were compared with 3GPP specifications."

Title: 116: Formal Specification and Verification of JXTA's Core Protocols for peer-to-peer Networks Authors: Yannik Kala Konga (French South African Institute of Technology), Karim Djouani (Tshwane University of

Technology) and Guillaume Noel (Tshwane University of Technology) Abstract: "JXTA protocols describe a platform for peer-to-peer networking, independent of underlying transport

protocols, for peer collaboration and message exchange. The JXTA project is an open source initiative and its protocols are informally specified as an exchange of XML-based messages between entities. This paper presents the formal specification and automated verification of its core protocols: the Endpoint Routing Protocol and the Peer Resolver Protocol. These protocols run at the core of the JXTA architecture and are respectively responsible for routing messages between peers and for resolving queries/responses for services and applications. The PROMELA based formal specification serves as input to the SPIN model checker to prove the presence of a logical flaw due to non-progress cycles."

Title: 151: Considerations for Dynamic Spectrum Access of TV White Space in South Africa Authors: Melvin Ferreira (North-West University) and Albert Helberg (North-West University) Abstract: "The Radio Interferometric Positioning System (RIPS) was developed by Maroti et al for the purpose of node

localization in wireless sensor networks. In RIPS measurements a value called a Q-range is determined. This Q-range is a linear combination of all distances between all the nodes and can be used to determine the relative positions of the nodes involved in the RIPS measurement. Ambiguity occurs in the Q-range when measurements are made using nodes that are separated by a distance greater than a carrier wavelength. This paper presents possible solutions for Q-range ambiguity based on a special case in Q-range ambiguity."

The Intelligent IP Edge Title: 103: Maintenance of Voice Quality Control in the Evolution to Packet Switched Wireless Networks Authors: Nikesh Nageshar (University of the Witwatersrand) and Rex Van Olst (University of the Witwatersrand) Abstract: "As wireless systems evolve from traditional circuit switch technology to packet based technology there is a

prerequisite that voice quality in packet switched networks be maintained to an acceptable level such that user experience is not compromised. At present all next generation wireless networks have been specified with packet based radio access network (RAN) which implies that the flaws of traditional packet based networks will now also apply to wireless networks. The following paper provides proposals to carriers for the maintenance of quality voice over 3.9, fourth generation (4G) and beyond, wireless networks. The paper illustrates the evolved packet core as well as the quality of service (QoS) mechanisms available in 4G packet switched wireless networks. As many carriers have been patient with their take up of IMS, solutions such as circuit switched fallback (CSFB), voice over generic access (VoLGA) and WiMAX voice are presented for consideration. A test bed consisting of WiMAX with differing service flows (SF) was configured and the test results for each of the WiMAX QoS service flows presented. The results illustrate superior performance for latency and jitter when utilising the ertPS (enhanced real time Polling Service) as well as the unsolicited grant service (UGS) as compared to the other service flow types. The results for each of the service flow types are compared and contrasted to determine the most appropriate type that is applicable to voice."

Title: 150: Vulnerability Discovery and Analysis within the Open Source IMS Core Authors: Denver Abrey (University of Cape Town) and Neco Ventura (University of Cape Town) Abstract: "VoIP has increasingly been adopted as a preferred method of communication and continues to gain

popularity. With operators looking to move to a converged service delivery platform, many are turning to IMS deployments to provide such services. Security is an essential part of any deployment, and it is beneficial to be aware of possible vulnerabilities, so they may be dealt with accordingly. This paper describes a method of locating vulnerabilities within an IMS deployment. It focuses on the Open Source IMS Core, and describes the discovery, analysis, and impact of vulnerabilities within. A technique called ‘fuzzing’ is used throughout for the discovery of vulnerabilities."

Title: 155: Modeling a SCIM for IMS Using a Converged Servlet Container Authors: Mosiuoa Tsietsi (Rhodes University), Alfredo Terzoli (Rhodes University) and George Wells (Rhodes

University) Abstract: "The composition of large systems from smaller building blocks is a common system design strategy. It makes

the process of introducing changes to such systems more economical and also supports the rapid development of entirely new systems. This technique is now being applied in telecommunication systems such as the IP Multimedia Subsystem (IMS) whereby standards development organisations have been actively encouraging network operators to build telecommunication services from basic components. In order to coordinate the interactions that must occur in a multi-component service, an IMS node called the Service Capability Interaction Manager (SCIM) has been proposed. Though the SCIM is central to realising the benefits of service decomposition, it has not yet been formally incorporated into the set of standards that constitute the IMS. This has left issues regarding the functional and structural architecture of the SCIM open to interpretation. This paper outlines the authors’ own interpretation of the architecture of the SCIM that stems from preliminary work initiated by the Third Generation Partnership Project (3GPP) as well as contemporary proposals by researchers in the field. The development of a prototype is described that has been built using a servlet container that supports the creation of converged SIP/HTTP applications. This investigation is part of a larger project aimed at providing an Extended IMS Service Layer (EISL) that is more conducive to the development and deployment of complex multimedia services in an IMS environment."

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Work In Progress: Access Network Technologies Title: 217: Development of a Distributed Video Streaming System using Application Layer Multicasting Authors: Samuel van Loggerenberg (North-West University) and Albert Helberg (North-West University) Abstract: "Video streaming over Ethernet-based networks are becoming very popular - with implementations such as

YouTube providing high quality streaming video over the internet. These streaming systems traditionally use a Content Delivery Network (CDN) consisting of a large number of servers with very high network bandwidth to meet the requirements of network-based video streaming. Alternatively, by distributing the server bandwidth requirement over a number of nodes, an Application Layer Multicasting (ALM) system can provide high quality video from a streaming video source to a large number of receivers with low latencies and minimal additional overhead. In this paper the development of a score-based Minimum Spanning Tree (MST) system for the distribution of real-time streaming video is presented."

Title: 224: MC-CDMA with Blind Channel Estimation and Adaptive Reception Authors: Nikolai de Figueiredo (University of Pretoria) and Louis Linde (University of Pretoria) Abstract: "Methods for blind channel estimation and equalisation have been identified. These include maximum

likelihood estimation, stochastic gradient algorithms and techniques based on higher-order statistics. The subspace based methods of channel identification are presented with a view to developing a low complexity subspace tracking algorithm. It is expected that a performance gain in terms of bandwidth efficiency will be achieved which is of utmost importance when developing future generation communication technologies."

Title: 226: UniCorn: A Web-Based Unified Communications Portal Authors: Brian Maunde (Rhodes University), Alfredo Terzoli (Rhodes University) and Mosiuoa Tsietsi (Rhodes

University) Abstract: "The proliferation of communication devices and applications, in their disparate and unsynchronised nature –

due to lack of interoperability, has resulted in several challenges that have reduced communication efficiency and user productivity. The unification of these applications or modalities via a single interface may help in addressing these challenges. This paper describes work in progress to develop a user-centric and web-based unified communications solution, UniCorn. This solution unifies text, voice and video based communication modalities and enhances their functionality by integrating presence and mobility. This may result in improved end user productivity and communication efficiency, reduction of communication costs, better contact management and improved mobility."

Title: 234: Wireless SIMO/MISO OFDM Implementation using the TMS320C6416 DSP Kits Authors: Preia Motheeram (University of Kwa-Zulu Natal), Weziwe Duma (University of Kwa-Zulu Natal) and Stanley

Mneney (University of Kwa-Zulu Natal) Abstract: "In this paper, we present the progress of the wireless implementation of a SIMO/MISO OFDM testbed using

Texas Instruments’ (TI) TMS320C6416 DSPs on Spectrum Digital developement platforms.The channel model, channel coding, synchronization technique and implementation results of this system are presented.The SISO OFDM testbed will be modified SIMO/MISO wireless OFDM transmission.The hardware interface required to convert the baseband signal from the DSP kits to RF are presented. Future work regarding the conversion of the SISO OFDM testbed to support multiple transmit and multiple receive antennas for performance measurements is discussed."

Title: 242: LTE-Advanced Uplink Scheduling Authors: Ronnie Mugisha (University of Cape Town) and Neco Ventura (University of Cape Town) Abstract: "LTE Advanced is expected to reach peak data rates of 1Gbps/500Mbps (UL/DL) against 100/50Mbps for LTE,

and it will do so mainly by using a technique called carrier Aggregation. In LTE bandwidths of about 20MHz can be used however LTE Advanced's carrier Aggregation groups consecutive normal LTE bandwidths from larger ones of up to 100MHz .Other techniques include both uplink and downlink transmissions to neighbouring base stations simultaneously.The introduction of these techniques means that current results obtained from the simulation of scheduling algorithms for LTE will not apply for LTE Advanced. This means that new and intelligent packet scheduling Algorithms which take into account new many more factors e.g. new types of interference will need to be developed .For instance the contiguity constraint imposed on LTE uplink is no longer present, which makes some current uplink algorithms irrelevant."

Title: 261: Practical Support Recovery using Sub-Nyquist Sampling Authors: Shanu Aziz (North-West University) and Albert S. J. Helberg (North-West University) Abstract: "This paper presents a work in progress on the support recovery in wideband analog signals. The paper

discusses an approach towards the spectrum sensing and carrier recovery of the frequency bands for cognitive radio (CR) operation. The purpose of this research is to design a simulation model and FPGA implementation of a method that detects the unused frequency regions using sub-Nyquist sampling and blind support recovery in sparse wideband analog signals for use in CR."

Title: 270: An Optimized Bicasting Scheme for Proxy Mobile IPv6 Authors: Lebajoa Mphatsi (University of Cape Town) and Olabisi Falowo (University of Cape Town) Abstract: "Current research in mobility management depicts that the trend in mobility management is moving towards

offering mobile users seamless connectivity across different access technologies. This entails minimizing packet loss and handover delay without compromising utilization of the limited wireless network resources. Bicasting Proxy Mobile IPv6 (B-PMIPv6) is one of the solutions proposed to achieve the desired mobility management objectives. B-PMIPv6 deals with packet loss by sending duplicate packets to both the current mobile access gateway (MAG) and the target mobile access gateway, thus offering a seamless IP handover. However, some of the current bicasting solutions for PMIPv6 start the bicasting process too early and stop too

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late, thus putting a strain on limited network resources, such as network buffers and backhaul bandwidth. In this work, we propose a bicasting solution to determine optimal times to start and stop bicasting while utilizing the backhaul bandwidth efficiently and avoiding buffer overflows that result from too early and too late bicasting. The description of the proposed bicasting scheme is presented in this paper."

Work In Progress: Internet Services & Applications Title: 229: A Mobile Phone Solution to Improve Geographic Mobility Authors: Sacha Miteche (Rhodes University), Alfredo Terzoli (Rhodes University) and Hannah Thinyane (Rhodes

University) Abstract: "Motor vehicle ride sharing is a popular way of travelling in most countries. Different incentives have made this

mode of travelling to exist formally and informally, for example as in carpooling clubs and hitchhiking respectively. Advances in Information and Communication Technology (ICT) have facilitated developments of formal Dynamic Ride Sharing (DRS) systems that target mobile devices. These are seen as solutions to people’s preference of flexible ride sharing services. In developing countries, hitchhiking is a common technique for ride sharing travels. This paper describes a proposal to develop a DRS system that primarily targets mobile phone users in South Africa for informal ride sharing methods done in hitchhiking."

Title: 230: Towards a Framework for Enhanced Mobile Computing Using Cloud Resources Authors: Andrew Paverd (University of Cape Town), Michael Inggs (University of Cape Town) and Simon Winberg

(University of Cape Town) Abstract: "As mobile devices become both computing tools as well as communications devices, mobile cloud computing

provides a means to enhance the computational capabilities of these devices. As an initial step in the development of this technology, this paper proposes a framework that identifies and defines various important aspects of mobile cloud computing. These aspects include computational and communication requirements, mobile network impact, energy considerations, information security, system availability and application usability."

Title: 237: High Speed Lexical Classification of Malicious URLs Authors: Shaun Egan (Rhodes University) and Barry Irwin (Rhodes University) Abstract: "It has been shown in recent research that it is possible to identify malicious URLs through lexical analysis of

their URL structures alone. Lightweight algorithms are defined as methods by which URLs are analyzed that do not use external sources of information such as WHOIS lookups, blacklist lookups and content analysis. These parameters include URL length, number of delimiters as well as the number of traversals through the directory structure and are used throughout much of the research in the paradigm of lightweight classification. Methods which include external sources of information are often called fully featured classifications and have been shown to be only slightly more effective than a purely lexical analysis when considering both false-positives and false-negatives. This distinction allows these algorithms to be run client side without the introduction of additional latency, but still providing a high level of accuracy through the use of modern techniques in training classifiers. Both AROW and CW classifier update methods will be used as prototype implementations and their effectiveness will be compared to fully featured analysis results. These methods are selected because they are able to train on any labeled data, including instances in which their prediction is correct, allowing them to build a confidence in specific lexical features."

Title: 245: A Fuzz Testing Framework for Evaluating and Securing Network Applications Authors: Sascha Zeisberger (Rhodes University) and Barry Irwin (Rhodes University) Abstract: "Research has shown that fuzz-testing is an effective means of increasing the quality and security of software

and systems. This project proposes the implementation of a testing framework based on numerous fuzz-testing techniques. The framework will allow a user to detect errors in applications and locate critical areas in the applications that are responsible for the detected errors. The aim is to provide an all-encompassing testing framework that will allow a developer to quickly and effectively deploy fuzz tests on an application and ensure a higher level of quality control before deployment."

Title: 258: Consequences of Software Design Decisions for Low-Income Communities: A Case Study Authors: Fritz Meissner (University of Cape Town) and Edwin Blake (University of Cape Town) Abstract: "This paper discusses how software design decisions can have a positive effect on broad contextual issues

which affect Information and Communication Technology for Development (ICT4D) projects. We present five decisions which we made during the design of a web application intended for use by members of low-income communities in Cape Town. Our decisions were based on our knowledge of the context of deployment but increased the effort required of the development team. We use the Bridges.org Real Access / Real Impact criteria to categorise the benefits of our decisions and justify our prioritisation of concerns other than minimising the development effort."

Title: 265: Towards Developing Failure Tolerant Communication Framework for GUISET Services Authors: Themba Shezi (University of Zululand), Edgar Jembere (University of Zululand) and Matthew Adigun

(University of Zululand) Abstract: "Abstract- Enterprise Service Bus (ESB) is now a popular term in today’s information systems integration

reflecting an implementation of Service Oriented Architecture (SOA). ESB act as an integration and communication platform for connecting heterogeneous services. There are many ESB solutions that have been implemented and available as both commercial and open source software. Within these solutions heterogeneous services exchange messages regardless of their nature, leading to a great flexibility of information sharing amongst these services. However, with all messages going through the bus - the ESB can

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quickly become a single point of failure for an organization. To ensure that communication between services continuously exist in case of ESB failure, this work proposes failure tolerant framework that is based on federation of ESBs. We intend to adopt distributed service registries between federation of ESBs to assist in publishing, finding and binding of heterogeneous services, and content based intelligent routing to facilitate communication in the ESB federation."

Title: 284: Offering Voice Services in the Evolved Packet Core and Ensuring Service Continuity during

Handoff Authors: Sibonelo Christopher Madlopha (University of Cape Town) and Neco Ventura (University of Cape Town) Abstract: "The 3GPP motivated by the hope of satiating the rising demand of data services has specified and

standardized an all IP network technology called the EPS. The EPS comprises of LTE for access and EPC as the core network. Unlike the previous network technologies, it has no inherent circuit switched domain for offering voice services. Voice has been, and still remains a key service in both wired and wireless networks. This then leads us to an interesting pair of questions: How do we offer voice services in LTE and how to ensure voice service continuity when a user moves out of LTE coverage. This research aims to find the most optimal and efficient solution not only for the end user but also the network operator. An investigation has been carried out to evaluate the already existing solutions. It is unclear which solution is the best, but there is evidence that all solutions will converge to the 3GPP IMS based solution as it has been widely accepted and standardised as a long term solution for offering voice services."

Work In Progress: Network Services Title: 223: Biometric Recognition Using NFC-enabled Smartphones Authors: Charl Anton Opperman (University of Pretoria) and Gerhard Petrus Hancke (University of Pretoria) Abstract: "It is proposed that smartphones with NFC will be studied as a tool to perform biometric identification and

verification. Modern smartphones are equipped with various sensors, fast processors and large memory capacities and are expected to perform adequately in terms of speed and accuracy. The utilisation of NFC communication is proposed to ensure speed and usability in the passing of biometric data between phones and to allow biometric data to be stored on RFID tags. Phones with biometric recognition capabilities may, for example, be applied in systems involving remote and mobile authentication with strict security requirements."

Title: 239: A Social Media Gateway for Enhanced IMS Service Provisioning Authors: Nicholas Katanekwa (University of Cape Town) and Neco Ventura (University of Cape Town) Abstract: "The IP Multimedia Subsystem (IMS) is a network architecture supporting the creation and delivery of

converged IP multimedia services to both fixed and mobile networks. IMS and other Telco services have in the recent past witnessed massive competition from innovative Web 2.0 based Social Media Services in the likes of Facebook, Twitter etc which are indicative of changing user communication patterns. This change in trends has led to a fragmentation of Telco revenues as user preferences are shifting from one to one/conversational to many to many/collaborative type of services enriched with sharing of information, music, video etc. This research proposes a strategy for Telcos to rise up to the challenge by enabling the delivery of enriched integrated IMS - Social Media Services to the Social Media Market through a Social Media Gateway over the IMS allowing access to these Mashup Services from Telco web portals and Social Networking Site web pages/profiles."

Title: 263: Towards a Model to Support the Visualisation of Telecommunication Service Utilisation Authors: Gianni Gurshwin Twigg (Nelson Mandela Metropolitan University) and Janet Wesson (Nelson Mandela

Metropolitan University) Abstract: "The telecommunication service industry is growing and becoming more competitive. Telecommunication

service providers are becoming more service-oriented in order to gain a competitive advantage. Monitoring and controlling of telecommunication service usage can provide management with information about how customers use their services, which can assist with improving service quality. There is currently a lack of tools for visualisation of telecommunication service usage to support business decision making. This research aims to identify how telecommunication service management (TSM) is currently managed and what problems exist. An investigation will be conducted to develop a model for mobile information visualisation that can be used to support TSM."

Title: 264: Towards a Model for Online Self-Service Telecommunication Service Provisioning Authors: Sherwin Barlow (Nelson Mandela Metropolitan University), Janet Wesson (Nelson Mandela Metropolitan

University) and Lester Cowley (Nelson Mandela Metropolitan University) Abstract: "The telecommunication industry is growing rapidly due to increasing numbers of people using

telecommunication services, such as the Internet. The telecommunication service provisioning market is becoming saturated as more companies providing similar services are entering the market. Companies are under pressure and need to implement techniques to retain and attract customers. Current systems do not provide effective self-service provisioning for all services offered. Customers are required to have knowledge about services when purchasing a service or have to rely on the assistance of a company expert. This makes the decision making process for customers difficult. The aim of this research is to identify problems in telecommunication service provisioning and propose a model to assist in online self-service telecommunication service provisioning by examining related approaches used to provide customer support, for example expert and recommender systems."

Title: 278: Characterisation of a proton exchange membrane electrolyser by electrochemical techniques Authors: Christiaan Martinson (North-West University), George van Schoor (North-West University) and Kenny Uren

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(North-West University), D. Bessarabov (North-West University), J.H.P. van der Merwe (North-West University) Abstract: "Electrolysers can be used in renewable energy systems to produce hydrogen with the hydrogen acting as an

energy carrier. This paper presents the characterisation of a proton exchange membrane (PEM) using electrochemical techniques. The characterisation will yield information about the different components of the PEM electrolyser. An equivalent electrolyser model will be used to accurately represent the current and voltage terminal characteristics as well as the energy transfer from electrical to hydrogen."

Title: 288: Free Space Optical Data Communication Link Authors: Siyanda Qhumayo (University of Johannesburg) and Rodolfo Martinez (University of Johannesburg) Abstract: "Abstract- In this paper, we present work in progress of the development of the Free Space Optical (FSO)

communication link using a multi-wavelength Erbium Doped fiber laser as a cost effective way to achieve high bandwidth data link. FSO links find applications in point-to-point links commonly used at University campus networks, closed circuit television (CCTV) security networks, supplements to Radio links and backup links for optical fiber communication links in enterprise networks."

Title: 292: Multipoint Fibre Sensor for Temperature Measurements Authors: Michelin Della Tamin (University of Johannesburg), R. Martínez Manuel (University of Johannesburg), J. T.

Guillen-Bonilla (University of Johannesburg) Abstract: "A multipoint fibre sensor for temperature measurements work in progress is presented. Multipoint temperature

fibre sensors can be used in industry for the monitoring of power transformers, jet engines, and furnaces. The aim of this project is to investigate, design and develop a multipoint temperature fibre sensor. This sensor is attractive because of its high sensitivity, high spatial resolution and its ability to measure temperature in different points simultaneously."

Work In Progress: Software Title: 218: Device Control for Ethernet AVB Networks Authors: James Dibley (Rhodes University) and Richard Foss (Rhodes University) Abstract: "Ethernet Audio Video Bridging (AVB) technology promises deterministic transmission for multimedia networks

and substantial enhancements in QoS mechanisms. Devices that implement Ethernet AVB technology require a remote control protocol. This paper describes an application built on the XMOS multithreaded architecture that implements remote control for an Ethernet AVB endpoint using the AES X170 protocol. The implementation of the AES X170 control server will allow evaluation of how parallelised implementation of control protocols can yield improvements for multimedia network performance."

Title: 222: Application of De-embedding Methods to Characterise Sections of Microwave Circuits Authors: Adam Swiatko (University of Pretoria) and Jan A. G. Malherbe (University of Pretoria) Abstract: "De-embedding is the process whereby the transmission properties of a section of microwave circuit, in

isolation from the rest of the circuit, are characterised. In this paper it is proposed that a new analysis tool be developed by using a combination of de-embedding methods as well as a numerical computational software package. The analysis tool can then be applied to a horn antenna to separate the transmission properties of the horn structure from the transmission properties of the transducer that is used to feed the system."

Title: 233: Video Fingerprinting using Robust Hashing Authors: Ruan Moolman (North-West University) and Willie C. Venter (North-West University) Abstract: "Video fingerprinting is a technique used to identify unknown video by matching the video to a known video

which has similar content. This is achieved by creating a video fingerprint of the unknown video and comparing it to a database of known video fingerprints. There are many different video fingerprinting techniques that have been proposed, each with their strengths and weaknesses. In this paper a novel video fingerprinting technique is proposed. The technique is primarily designed for advertisement identification on a real-time video stream. For this purpose, robustness and speed are very important aspects of the algorithm. This fingerprinting technique is frame-based and makes use of the Scale Invariant Feature Transform algorithm and Shazam-like hashing between key points in different frames in a video sequence to create fingerprints."

Title: 238: Towards the Design of an Efficient Data Warehousing Architecture for Analysing Online Resource

Usage Data Authors: Cornel Ferreira (Nelson Mandela Metropolitan University), Charmain Cilliers (Nelson Mandela Metropolitan

University) and Brenda Scholtz (Nelson Mandela Metropolitan University) Abstract: "Abstract - Online Resource Usage data is generated by organisations in large amounts and has the potential

to significantly support the decision making processes of an organisation. In order to enable organisations to utilise the advantages of analysing this data, a suitable and efficient data warehousing architecture is required, which is designed using best practices. This paper reports on initial research done to investigate the design of a data warehousing architecture to support efficient analysis of online resource usage data."

Title: 251: Faster Upper Body Pose Estimation Using CUDA Authors: Dane Lesley Brown (University of the Western Cape), Mehrdad Ghaziasgar (Rhodes University), James

Connan (Rhodes University) Abstract: "Determining upper body poses using computer vision can have long execution times when using traditional

linear methods on the CPU. This paper shows how parallel processing methods, and in particular the usage of a GPU API called CUDA, can increase system performance."

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Title: 273: Eye detection in complex environments using Gabor filters Authors: Jacques de Villiers (University of Johannesburg), Yuko Roodt (University of Johannesburg) and Andre Nel

(University of Johannesburg) Abstract: "Eye detection has many applications in computer vision systems. In this article, we propose an eye detection

algorithm that trains Gabor filters to describe eye features and later detect eyes in unconstrained environments. Skin color information detects image regions that have higher probabilities of containing eyes. The Chromatic colour space will be trained to model skin colour. Separable Gabor filters are used to substantially decrease computation time. For an interactive experience the algorithms are executed on the Graphics Processing Unit (GPU)."

Title: 291: Blueprints for Developing Software Components within Teleweaver, a Custom OSGi Container Authors: Lindikaya Ntshinga (Rhodes University), Mamello Thinyane (Rhodes University), Alfredo Terzoli (Rhodes

University) Abstract: "Component Based Development (CBD) is a popular approach for developing complex systems. It often offers

a strong potential for reuse and dynamic plug-and-play. However design, implementation and deployment of components often presents a challenge to software developers. The work reported in this paper explores best practices for developing software components using Open Services Gateway Initiative (OSGi), in the context of Teleweaver, with the aim of preparing blueprints for the main classes of components OSGi is a framework that supports the implementation of component-based, service-oriented applications in Java. Teleweaver is a lightweight, custom built OSGi container targeted at rural and marginalised communities in Southern Africa. Component classification is naturally the first step towards the blueprints and we are currently busy with this."