Technical Report on Deploying a highly secured OpenStack Cloud Infrastructure using BradStack as a Case Study

Cloud computing has emerged as a popular paradigm and an attractive model for providing a reliable distributed computing model.it is increasing attracting huge attention both in academic research and industrial initiatives. Cloud deployments are paramount for institution and organizations of all scales. The availability of a flexible, free open source cloud platform designed with no propriety software and the ability of its integration with legacy systems and third-party applications are fundamental. Open stack is a free and opensource software released under the terms of Apache license with a fragmented and distributed architecture making it highly flexible. This project was initiated and aimed at designing a secured cloud infrastructure called BradStack, which is built on OpenStack in the Computing Laboratory at the University of Bradford. In this report, we present and discuss the steps required in deploying a secured BradStack Multi-node cloud infrastructure and conducting Penetration testing on OpenStack Services to validate the effectiveness of the security controls on the BradStack platform. This report serves as a practical guideline, focusing on security and practical infrastructure related issues. It also serves as a reference for institutions looking at the possibilities of implementing a secured cloud solution.Comment: 38 pages, 19 figures

Investigating factors influencing the decision making process for ERP adoption and implementation: An exploratory case study

The rapid developments in Information and Communication Technologies (ICT) have resulted into a borderless business environment along with an amplified market competition. Traversing through such a trend globally, organisations have significantly focused on adopting and implementing Enterprise Resource Planning (ERP) systems to automate their prime business processes, enhance organisational productivity with lower costs and prompt service delivery to fulfil consumer demands. Thus, ERP systems are considered as a principal source to provide imperative information vital for strategic decision making process. On the contrary, ERP systems adoption and implementation is also highly considered as a challenging and expensive process that not only requires rigorous efforts but also demands to have an exhaustive investigation of influential factors that are critical to the adoption and implementation of ERP systems. A plethora of research studies have been theorised exploring factors influencing the decision making process for ERP adoption and implementation; however, the authors claim that these studies are not filtered comprehensively in terms of the different perspectives. Notwithstanding, the implications of such research have yet to be assessed, leaving scope for timeliness and novel research. This paper thus focuses on the ERP critical success factors from five different perspectives such as: stakeholders; process; technology; organisation; and project based on the literature analysis. These perspectives comprise of 24 factors that are imperative for a successful ERP adoption and implementation, which are validated through a qualitative single case study based research. The empirical findings illustrate that these factor help realise significant benefits such as reducing costs and saving time or extra effort

Asymptotically Optimal Approximation Algorithms for Coflow Scheduling

Many modern datacenter applications involve large-scale computations composed of multiple data flows that need to be completed over a shared set of distributed resources. Such a computation completes when all of its flows complete. A useful abstraction for modeling such scenarios is a {\em coflow}, which is a collection of flows (e.g., tasks, packets, data transmissions) that all share the same performance goal. In this paper, we present the first approximation algorithms for scheduling coflows over general network topologies with the objective of minimizing total weighted completion time. We consider two different models for coflows based on the nature of individual flows: circuits, and packets. We design constant-factor polynomial-time approximation algorithms for scheduling packet-based coflows with or without given flow paths, and circuit-based coflows with given flow paths. Furthermore, we give an $O(\log n/\log \log n)$-approximation polynomial time algorithm for scheduling circuit-based coflows where flow paths are not given (here $n$ is the number of network edges). We obtain our results by developing a general framework for coflow schedules, based on interval-indexed linear programs, which may extend to other coflow models and objective functions and may also yield improved approximation bounds for specific network scenarios. We also present an experimental evaluation of our approach for circuit-based coflows that show a performance improvement of at least 22% on average over competing heuristics.Comment: Fixed minor typo

Toda Lattice Hierarchy and Zamolodchikov's Conjecture

In this letter, we show that certain Fredholm determinant $D(\lambda;t)$, introduced by Zamolodchikov in his study of 2D polymers, is a continuum limit of soliton solution for the Toda lattice hierarchy with 2-periodic reduction condition.Comment: 6 pages, LaTeX file, no figure

Did silicon aid in the establishment of the first bacterium?

Silicic acid increased numbers of both aerobic and facultatively anaerobic bacteria in ultrapure water incubated under strict oligotrophic conditions; soil extracts acted as the bacterial inoculum. The results are discussed in relation to the possibility that silicic acid, produced by the hydrolysis of silicates on the early Earth, could have stimulated the growth of the first bacterium, thereby allowing it to become established in the then prevailing conditions (presumed to be oligotrophic)

Orbital Fluctuation-Induced Triplet Superconductivity : Mechanism of Superconductivity in Sr2RuO4{\rm Sr}_{2}{\rm RuO}_{4}

The mechanism of superconductivity in ${\rm Sr}_{2}{\rm RuO}_{4}$ is studied using a degenerate Hubbard model within the weak coupling theory. When the system approaches the orbital instability which is realized due to increasing the on-site Coulomb interaction between the electrons in the different orbitals, it is shown that the triplet superconductivity appears. This superconducting mechanism is only available in orbitally degenerate systems with multiple Fermi surfaces.Comment: 5 pages, 4 figure

On some generalized ageing orderings

Some partial orderings which compare probability distributions with the expo- nential distribution, are found to be very useful to understand the phenomenon of ageing. Here, we introduce some new generalized partial orderings which de- scribe the same kind of characterization of some generalized ageing classes. We give some equivalent conditions for each of the orderings. Inter-relations among the generalized orderings have also been discussed

Electron localization and a confined electron gas in nanoporous inorganic electrides

The nanoporous main group oxide 12CaO.7Al(2)O(3) (C12A7) can be transformed from a wide-gap insulator to an electride where electrons substitute anions in cages constituting a positive frame. Our ab initio calculations of the electronic structure of this novel material give a consistent explanation of its high conductivity and optical properties. They show that the electrons confined in the inert positive frame are localized in cages and undergo hopping between neighboring cages. The results are useful for the understanding of behavior of confined electron gas of different topology and electron-phonon coupling, and for designing new transparent conductors, electron emitters, and electrides