A Taxonomy of Data Grids for Distributed Data Sharing, Management and Processing

Data Grids have been adopted as the platform for scientific communities that need to share, access, transport, process and manage large data collections distributed worldwide. They combine high-end computing technologies with high-performance networking and wide-area storage management techniques. In this paper, we discuss the key concepts behind Data Grids and compare them with other data sharing and distribution paradigms such as content delivery networks, peer-to-peer networks and distributed databases. We then provide comprehensive taxonomies that cover various aspects of architecture, data transportation, data replication and resource allocation and scheduling. Finally, we map the proposed taxonomy to various Data Grid systems not only to validate the taxonomy but also to identify areas for future exploration. Through this taxonomy, we aim to categorise existing systems to better understand their goals and their methodology. This would help evaluate their applicability for solving similar problems. This taxonomy also provides a "gap analysis" of this area through which researchers can potentially identify new issues for investigation. Finally, we hope that the proposed taxonomy and mapping also helps to provide an easy way for new practitioners to understand this complex area of research.Comment: 46 pages, 16 figures, Technical Repor

The embeddedness of global production networks: The impact of crisis on Fiji's garment export sector

In this paper the author explores how changing geopolitical conditions reconfigure network embeddedness and theorises the conditions of network disconnection and transformation. Through a case study of the changes in interfirm relationships within the Fiji – Australia garment-production network after Fiji’s 2000 political coup d’état, the author develops a relational and dynamic view of embeddedness, highlighting its multifaceted and multiscalar character and emphasising the interrelationships between embeddedness, trust, and power

Secure and robust multi-constrained QoS aware routing algorithm for VANETs

Secure QoS routing algorithms are a fundamental part of wireless networks that aim to provide services with QoS and security guarantees. In Vehicular Ad hoc Networks (VANETs), vehicles perform routing functions, and at the same time act as end-systems thus routing control messages are transmitted unprotected over wireless channels. The QoS of the entire network could be degraded by an attack on the routing process, and manipulation of the routing control messages. In this paper, we propose a novel secure and reliable multi-constrained QoS aware routing algorithm for VANETs. We employ the Ant Colony Optimisation (ACO) technique to compute feasible routes in VANETs subject to multiple QoS constraints determined by the data traffic type. Moreover, we extend the VANET-oriented Evolving Graph (VoEG) model to perform plausibility checks on the exchanged routing control messages among vehicles. Simulation results show that the QoS can be guaranteed while applying security mechanisms to ensure a reliable and robust routing service

Secure Routing Environment with Enhancing QoS in Mobile Ad-Hoc Networks

A mobile adhoc network is infrastructure-free and self configured network connected without wire. As it is infrastructure-free and no centralized control, such type of network are suitable only for conditional inter communication link. So initially maintaining Quality of Service and security aware routing is a difficult task. The main purpose of QoS aware routing is to find an optimal secure route from source to destination which will satisfy two or more QoS constrain. In this paper, we propose a net based multicasting routing scheme to discovery all possible secure path using Secure closest spot trust certification protocol (SCSTC) and the optimal link path is derived from Dolphin Echolocation algorithm (DEA). The numerical result and performance analysis clearly describe that our provided proposal routing protocol generates better packet delivery ratio, decreases packet delay reduces overhead in secured environment

Agglomerative Magnets and Informal Regulatory Networks: Electricity Market Design Convergence in the USA and Continental Europe

The absence of one broadly accepted design template for liberalised electricity markets induces regulatory competition and institutional diversity. Focussing on continental Europe and the USA, this analysis explores how agents and structures accelerate or impede the move to one standard market design in the electricity sector. It reveals that market design convergence in Europe is driven by the 'Florence Consensus,' a tripartite coalition between the European Commission fostering European integration and the internal market, informal regulatory networks between grid operators, standardisation authorities and regulators, who have been coordinating their actions in the 'Florence Forum,' and epistemic communities exemplified in the Florence School of Regulation. In contrast, the United States' Federal Energy Regulatory Commission lacks support among politicians, many states' public utility commissions, the neo-liberal intelligentsia and even industrial lobbying groups to effectively push for a standardised market design. However, design convergence in the USA may be induced by the gradual expansion of multi-state markets operated by regional transmission organisations.Electricity, Deregulation, Regulatory Competition, Policy Diffusion

Two-tier Intrusion Detection System for Mobile Ad Hoc Networks

Nowadays, a commonly used wireless network (i.e. Wi-Fi) operates with the aid of a fixed infrastructure (i.e. an access point) to facilitate communication between nodes when they roam from one location to another. The need for such a fixed supporting infrastructure limits the adaptability of the wireless network, especially in situations where the deployment of such an infrastructure is impractical. In addition, Wi-Fi limits nodes' communication as it only provides facility for mobile nodes to send and receive information, but not reroute the information across the network. Recent advancements in computer network introduced a new wireless network, known as a Mobile Ad Hoc Network (MANET), to overcome these limitations. MANET has a set of unique characteristics that make it different from other kind of wireless networks. Often referred as a peer to peer network, such a network does not have any fixed topology, thus nodes are free to roam anywhere, and could join or leave the network anytime they desire. Its ability to be setup without the need of any infrastructure is very useful, especially in geographically constrained environments such as in a military battlefield or a disaster relief operation. In addition, through its multi hop routing facility, each node could function as a router, thus communication between nodes could be made available without the need of a supporting fixed router or an access point. However, these handy facilities come with big challenges, especially in dealing with the security issues. This research aims to address MANET security issues by proposing a novel intrusion detection system that could be used to complement existing prevention mechanisms that have been proposed to secure such a network. A comprehensive analysis of attacks and the existing security measures proved that there is a need for an Intrusion Detection System (IDS) to protect MANETs against security threats. The analysis also suggested that the existing IDS proposed for MANET are not immune against a colluding blackmail attack due to the nature of such a network that comprises autonomous and anonymous nodes. The IDS architecture as proposed in this study utilises trust relationships between nodes to overcome this nodes' anonymity issue. Through a friendship mechanism, the problems of false accusations and false alarms caused by blackmail attackers in global detection and response mechanisms could be eliminated. The applicability of the friendship concept as well as other proposed mechanisms to solve MANET IDS related issues have been validated through a set of simulation experiments. Several MANET settings, which differ from each other based on the network's density level, the number of initial trusted friends owned by each node, and the duration of the simulation times, have been used to study the effects of such factors towards the overall performance of the proposed IDS framework. The results obtained from the experiments proved that the proposed concepts are capable to at least minimise i f not fully eliminate the problem currently faced in MANET IDS

An end-to-end bidirectional authentication system for pallet pooling management through blockchain internet of things (BIoT)

Pallet pooling is regarded as a sustainable and cost-effective measure for the industry, but it is challenging to advocate due to weak data and pallet authentication. In order to establish trust between end-users and pallet pooling services, the authors propose an end-to-end, bidirectional authentication system for transmitted data and pallets based on blockchain and internet-of-things (IoT) technologies. In addition, secure data authentication fosters the pallet authenticity in the whole supply chain network, which is achieved by considering the tag, location, and object-specific features. To evaluate the object-specific features, the scale invariant feature transform (SIFT) approach is adopted to match key-points and descriptors between two pallet images. According to the case study, it is found that the proposed system provides a low bandwidth blocking rate and a high probability of restoring complete data payloads. Consequently, positive influences on end-user satisfaction, quality of service, operational errors, and pallet traceability are achieved through the deployment of the proposed system

Barriers to implementation of the (SA) National Cybersecurity Policy Framework

Thesis (M.M. (Security))--University of the Witwatersrand, Faculty of Commerce, Law and Management, Graduate School of Public and Development Management, 2016Technological advancement have seen South African government departments, state owned entities and private companies using cyberspace as a platform of interaction and the storage of information. Technological advancements have a positive impact due to the compression of space, time and thereby ensuring fastpaced interaction across borders. These technological advancements have, however resulted in most organisations, both private and public, becoming prone to cybercrimes and related incidents. In an initiative aimed at countering these threats, the South African government has passed various laws. The National Cybersecurity Policy Framework (NCPF) is a South African Policy framework aimed at countering an increase in the occurrence of cybercrimes and related incidents. This research analyses the status in the implementation of the NCPF objectives allocated to the Department of Telecommunications and Postal Services (DTPS). Then the barriers in the Implementation are unpacked guided by the literature reviewed and finally recommendations on how to counter the identified barriers are provided post the data collection. The report firstly provides an outline of the global perspectives on cybersecurity which is followed by the regional cybersecurity measures, and then the national cybersecurity measures proposed by the South African Government department are outlined. The latter parts of the report focuses on the NCPF in terms of its scope, goals, objectives and stakeholders. Finally, focus is shifted to the DTPS as a chosen area of research wherein data was collected in a form of one-on-one, semi-structured interviews with relevant parties. The results of this research are presented as a narrative description that is synthesised to develop the theoretical conjecture and empirical generalisation of the entire research. This research uncovered that there are numerous barriers in the implementation of the NCPF both within the DTPS as well as between the DTPS and various stakeholders entrusted with the implementation responsibility. The last chapter consists of general conclusions made by the researcher based on the research conducted which is then followed by recommended countermeasures which will be communicated to the DTPS as well as all stakeholders who will be affected by the proposed recommendations.GR201