Broadband – it’s a word that has become synonymous with progress, with innovation, and with the rise in new ways for humans and machines to connect and share information. Billions of devices operate on various types of broadband networks across the globe and several billions more will soon be added. These networks are profoundly changing the world we live in. With the evolution of 4G, for example, a great number of fascinating new services and usage models are expected. Highly scalable and reliable networks with heterogeneous access technologies will enable critical applications in fixed/mobile environments offering quality accountability and security to applications and users.
At the UCT Centre of Excellence (CoE) in Broadband Networks and Applications, research is being done today that will give rise to a greater understanding of these powerful broadband networks, and how they work and how they can change the way the world works.
As an interdisciplinary Centre for research in advanced networking systems, the centre moves beyond traditional boundaries. It harnesses the power of collaboration, involving research groups from both the Department of Electrical Engineering and the Department of Computer Science. There is an emphasis on industry relevance and the Centre serves postgraduate students who have the desire and ability to bring cutting-edge new knowledge to light and who strive for innovative solutions. There has never been a more exciting time to be at the leading edge of broadband research, particularly in South Africa and in Africa. The current research at the Centre focuses on addressing multiple facets of information processing problems and on improving the support for emerging languages in search engines. This is exemplified by active research on knowledge management systems web-based systems and digital libraries of information storage, amongst others. Another area of focus is the investigation of wireless meshed networks for use in rural areas.
The programme is sponsored by Telkom SA, Nokia Siemens Networks, Ericsson South Africa, TeleSciences, the National Research Foundation and the Department of Trade and Industry.
Network Services and Management
Nowadays, it is vital for organizations and businesses to have access to high-speed communications networks in order to maintain a competitive edge in today’s fast-moving global market. This network access not only needs to be fast and reliable but also affordable for the average ICT consumer.
The concept of a converged network, which delivers voice, image, video and generalized data types over the same network using the Internet Protocol (IP) has become a major part of the solution to speedy and low-cost public networks. Research into converged networks includes ways to make them simpler, better and cheaper for the end-users, as well as technology developers making more effective use of the infrastructure and minimising operational costs for service providers.
Furthermore, user-centric networking enables the creation, composition and dynamic management of services, demanding high degrees of availability of network resources. Cooperative networking, implementing complex interactions and negotiation models for network-wide resource coordination relies on a pool of virtual servers configured as virtualization domains. Live migration of network resources is a core feature, allowing the running services to be relocated on the fly to another virtualized host, having a higher degree of resource availability. Novel management methods based on mobile agents will allow the virtualized network resources instances to be created, started, stopped, duplicated, or instructed to self-terminate. Next Generation Services are to be tested/deployed in multicasting aware networks such as VLPS over MPLS backbones.
Within the field of communications, the University of Cape Town offers a number of postgraduate research opportunities in the Department of Electrical Engineering. The Department offers both a PhD and MSc degree program by full research thesis, in addition to a MSc by coursework and mini thesis.
The networks systems research group at UCT is carrying out a variety of projects that aim to address challenges in a range of areas. The projects include research related to data communications, telecommunication and data network architectures, wireless networks and satellite communications – most of these are at the forefront of global innovations and are pivotal for the country. Four main themes are outlined below to provide some insight to what work is being done in the group.
Cognitive Radios Design for Intelligent Next Generation Wireless Networking
Cognitive radio technologies make use of the unused licensed spectrum to serve secondary users without interfering with the primary users. Predicting the white space in the spectrum together with the concurrent access of multiple cognitive radios is an important research task. Predicting the availability of white space and how long it will be present in a given bandwidth is a challenge, affecting the secondary users seeking for some QoS parameters for their own access to the white spectrum. The following are open research areas:
- signalling protocol suitable for cognitive radio enabled networks;
- prevention of collisions among cognitive radios;
- enabling cooperation amongst cognitive radios;
- maximizing the efficiency of available white usage.
Monitoring, Cooperation and Resource Coordination in Next Generation Networks
Current telecoms technologies development still suffers from the inherent flaws related to efficient and scalable resource usage patterns, which demand that network operators consider a transition process to the Next Generation Networks (NGNs). This will enhance the global roaming, mobility and performance of entire networks, as users of mobile devices have unrestricted access to different service providers.
This research project proposes a cooperative framework, which is able to facilitate network operators’ transition paths, and which deploys reconfigurable mobile network agents (RMNA) that can autonomously decentralize processing and control, hence effectively responding to shortage of network resources and reducing the amount the traffic around the management station.
Service Protection and Availability Enhancement in MPLS Networks
The modern communication networks are experiencing an increase in multimedia traffic. Such multimedia applications have stringent quality of service requirements with regard to delay, bandwidth and availability. These applications also have to be provided with prompt and efficient recovery methods from network failures. This research project focuses on the service protection in IP/MPLS networks. The focus is on guaranteeing the real-time quality of protection for multimedia traffic, defined as the effectiveness of the failure handling.
Mobile Networking Technologies for E-Learning
The application of Mobile Ad hoc NETworks (MANETs) in E-Learning provides a convenient information and communication technology solution in terms of economic viability, portability of devices and ease of deployment in highly dynamic environments. A MANET network is a self-organising and rapidly deployable network, which does not have a fixed infrastructure. Nodes in MANETs cooperate to form the necessary infrastructure, which makes multi-hop communication possible. This research is motivated by the need of adaptive data transmission protocols with the ability to exploit the characteristics of the underlying physical network in E-learning classroom environments, where topology changes are fairly predictable.
Education through Research
Fixed-mobile convergence and voice-data aggregation networks lead to the Next-Generation Networks delivering applications and integrated multimedia services. Understanding trends in network convergence enabling the Next Generation Networks to deliver IP-based services to user terminals moving between fixed and wireless access technologies and roaming between operator networks is a key perspective on the future ICT environment.
The educational offer in research context includes:
- Network Interoperability: PSTN, hierarchical networks, LAN/SOHO networks, access networks, WAN, Internet and core networks.
- Data Plane Technologies: multiplexing, L2/L3/L4 switching, routing, multicasting.
- Control Plane Technologies: signaling principles, call set-up, connection control, SS7, H.323, SIP, MPLS, SNMP.
- Network Virtualization: Principles and requirements; network virtualization elements and deployment, VPN, VPLS.
- Services Management: service requirements, qualifiers and management; SDP, APIs, Parlay, JAIN; service composition.
- NGN Service Platforms: multiservice platforms, soft-switches, cluster servers, Asterisk.
- Service Clouds: SOA, Cloud Computing; resource sharing, pooling and splitting; service models, monitoring and governance; content distribution networks.
- Applications Management: packetized voice telephony, video streaming, multimedia data networks, VoIP, IPTV, server replication and migration.