82 research outputs found

    Auto-Configuration of ACL Policy in Case of Topology Change in Hybrid SDN

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    © 2016 IEEE. Software-defined networking (SDN) has emerged as a new network architecture, which decouples both the control and management planes from data plane at forwarding devices. However, SDN deployment is not widely adopted due to the budget constraints of organizations. This is because organizations are always reluctant to invest too much budget to establish a new network infrastructure from scratch. One feasible solution is to deploy a limited number of SDN-enabled devices along with traditional (legacy) network devices in the network of an organization by incrementally replacing traditional network by SDN, which is called hybrid SDN (Hybrid SDN) architecture. Network management and control in Hybrid SDN are vital tasks that require significant effort and resources. Manual handling of these tasks is error prone. Whenever network topology changes, network policies (e.g., access control list) configured at the interfaces of forwarding devices (switches/routers) may be violated. That creates severe security threats for the whole network and degrades the network performance. In this paper, we propose a new approach for Hybrid SDN that auto-detects the interfaces of forwarding devices and network policies that are affected due to change in network topology. In the proposed approach, we model network-wide policy and local policy at forwarding device using a three-tuple and a six-tuple, respectively. We compute graph to represent the topology of the network. By using graph difference technique, we detect a possible change in topology. In the case of topology change, we verify policy for updated topology by traversing tree using six-tuple. If there is any violation in policy implementation, then affected interfaces are indicated and policies that need to be configured are also indicated. Then, policies are configured on the updated topology according to specification in an improved way. Simulation results show that our proposed approach enhances the network efficiency in term of successful packet delivery ratio, the ratio of packets that violated the policy and normalized overhead

    Discovering “unknown known” security requirements

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    Security is one of the biggest challenges facing organisations in the modern hyper-connected world. A number of theoretical security models are available that provide best practice security guidelines and are widely utilised as a basis to identify and operationalise security requirements. Such models often capture high-level security concepts (e.g., whitelisting, secure configurations, wireless access control, data recovery, etc.), strategies for operationalising such concepts through specific security controls, and relationships between the various concepts and controls. The threat landscape, however, evolves leading to new tacit knowledge that is embedded in or across a variety of security incidents. These unknown knowns alter, or at least demand reconsideration of the theoretical security models underpinning security requirements. In this paper, we present an approach to discover such unknown knowns through multi-incident analysis. The approach is based on a novel combination of grounded theory and incident fault trees. We demonstrate the effectiveness of the approach through its application to identify revisions to a theoretical security model widely used in industry

    Influence of Glass Fibers on Mechanical Properties of Concrete with Recycled Coarse Aggregates

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    Despite plain cement concrete presenting inferior performance in tension and adverse environmental impacts, it is the most widely used construction material in the world. Consumption of fibers and recycled coarse aggregates (RCA) can add ductility and sustainability to concrete. In this research, two mix series (100%NCA, and 100%RCA) were prepared using four different dosages of GF (0%GF, 0.25%GF, 0.5%GF, and 0.75%GF by volume fraction).  Mechanical properties namely compressive strength, splitting tensile strength, and flexural strength of each concrete mixture was evaluated at the age of 28 days. The results of testing indicated that the addition of GF was very useful in enhancing the split tensile and flexural strength of both RCA and NCA concrete. Compressive strength was not highly sensitive to the addition of GF. The loss in strength that occurred due to the incorporation of RCA was reduced to a large extent upon the inclusion of GF. GF caused significant improvements in the split tensile and flexural strength of RCA concrete. Optimum dosage of GF was determined to be 0.25% for NCA, and 0.5% for RCA concrete respectively, based on the results of combined mechanical performance (MP)

    Insight of Tp53 Mutations and their effect on Protein in Different Feline and Canine Neoplasms

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    Background: Mutations in the Tp53 gene, a tumor suppressor gene, may cause dysfunction in growing cells and hinder the phenomenon of apoptosis, an alleged cause of tumorigenesis. It is involved in conservation of the genome and DNA repair, mutations of this gene may cause the damaged cells to grow continuously.Methods: The type of molecular changes in Tp53 gene and their effects on physiochemical and structural properties of this protein in various Canine and Feline cancers were observed in this study by using online bioinformatics tools.Results: Our results indicated that lymphomas and perianal adenocarcinomas (PAC) have the same mutation at c. 104, while mammary tumors and canine transmissible venereal tumor (CTVT) contain different mutations. Referring to changes in protein, synonymous mutations in granulomas were observed while certain mutations in squamous cell carcinoma (SCC) and head & neck tumors were detected in Canis familiaris. In Felis catus, the mutant protein was similar to wild type protein with exception of mutant 5 of mammary tumor, which had a deletion at the 287 amino acid position.Conclusion: The insight gathered on the p53 mutant proteins in both species aided our understanding of the in-vivo fate of the p53 protein and its isoforms and the effects that morphological changes can have on the fate of cells. Furthermore, isolation of this protein may augment our understanding about the structural biology of these proteins

    Data Exfiltration:A Review of External Attack Vectors and Countermeasures

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    AbstractContext One of the main targets of cyber-attacks is data exfiltration, which is the leakage of sensitive or private data to an unauthorized entity. Data exfiltration can be perpetrated by an outsider or an insider of an organization. Given the increasing number of data exfiltration incidents, a large number of data exfiltration countermeasures have been developed. These countermeasures aim to detect, prevent, or investigate exfiltration of sensitive or private data. With the growing interest in data exfiltration, it is important to review data exfiltration attack vectors and countermeasures to support future research in this field. Objective This paper is aimed at identifying and critically analysing data exfiltration attack vectors and countermeasures for reporting the status of the art and determining gaps for future research. Method We have followed a structured process for selecting 108 papers from seven publication databases. Thematic analysis method has been applied to analyse the extracted data from the reviewed papers. Results We have developed a classification of (1) data exfiltration attack vectors used by external attackers and (2) the countermeasures in the face of external attacks. We have mapped the countermeasures to attack vectors. Furthermore, we have explored the applicability of various countermeasures for different states of data (i.e., in use, in transit, or at rest). Conclusion This review has revealed that (a) most of the state of the art is focussed on preventive and detective countermeasures and significant research is required on developing investigative countermeasures that are equally important; (b) Several data exfiltration countermeasures are not able to respond in real-time, which specifies that research efforts need to be invested to enable them to respond in real-time (c) A number of data exfiltration countermeasures do not take privacy and ethical concerns into consideration, which may become an obstacle in their full adoption (d) Existing research is primarily focussed on protecting data in ‘in use’ state, therefore, future research needs to be directed towards securing data in ‘in rest’ and ‘in transit’ states (e) There is no standard or framework for evaluation of data exfiltration countermeasures. We assert the need for developing such an evaluation framework

    A paradigm of blockchain and supply chain performance: a mediated model using structural equation modeling

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    Purpose – This paper aims to find the impact of blockchain supply chain on supply chain performance with a mediating role of supplier trust, traceability and transparency. Design/methodology/approach – Data was collected using the purposive sampling technique on a fivepoint Likert scale from 150 respondents. For data analysis, IBM SPSS and Smart PLS 3.3.7 were used to test the hypotheses by evaluating the structural equation modeling. Findings – The blockchain supply chain found a significant effect on supply chain performance. Moreover, there is a substantial effect of the blockchain supply chain on supply chain performance via mediators, including supplier trust, supply chain traceability and supply chain transparency. Further, the mediation type of all mediators was full mediation in the relationships between blockchain supply chain and supply chain performance. Research limitations/implications – The research findings are helpful for industrialists, supply chain practitioners and policymakers. The practitioners can adopt blockchain technology to enhance interorganizational collaboration, develop trust, data visibility and traceability, and critical decisions, ultimately bringing sustainable growth for the firm. Originality/value – The outcomes of this research enrich the literature and share the impact of one of the most trending technologies in the supply chain perspective. Future research can empirically test the relationship between blockchain and supply chain sustainability

    Examining the effectiveness of consuming flour made from agronomically biofortified wheat (Zincol-2016/NR-421) for improving Zn status in women in a low resource setting Pakistan: Study protocol for a randomised, double blind, controlled cross over trial (BiZiFED)

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    Introduction: Dietary zinc (Zn) deficiency is a global problem, particularly in low and middle-income countries where access to rich, animal-source foods of Zn is limited due to poverty. In Pakistan, Zn deficiency affects over 40% of the adult female population, resulting in sub-optimal immune status and increased likelihood of complications during pregnancy. Methods and analysis: We are conducting a double blind, randomised controlled feeding study with crossover design, in a low resource setting in Pakistan. Households were provided with flour milled from genetically and agronomically biofortified grain (Zincol-2016/NR-421) or control grain (Galaxy-2013. Fifty households were recruited. Each household included a female aged 16-49 years who is neither pregnant nor breastfeeding, and not currently consuming nutritional supplements. These women were the primary study participants. All households were provided with control flour for an initial 2-week baseline period, followed by an 8-week intervention period where 25 households receive biofortified flour (Group A) and 25 households receive control flour (Group B). After this eight-week period, Group A and B crossed over, receiving control and biofortified flour respectively for eight weeks. Tissue (blood, hair and nails) have been collected from the women at five time points: baseline, mid and end of period 1, mid and end of period 2. Ethics and dissemination: Ethical approval was granted from the lead University (reference number: STEMH 697 FR) and the collaborating institution in Pakistan. The final study methods (including any modifications) will be published in peer reviewed journals, alongside the study outcomes on completion of the data analysis. In addition, findings will be disseminated to the scientific community via conference presentations and abstracts and communicated to the study participants through the village elders at an appropriate community forum

    Physiological and Biochemical Response of Maize (Zea mays L.) to Exogenic Application of Boron under Drought Stress

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    An experiment was conducted at the Agronomic Research Area, University of Agriculture, Faisalabad, during autumn 2011 to determine the response of maize to foliar application of boron under water stress conditions. The experimental site is located at 73.09 0 E longitudes, 31.25 0 N latitudes with semi-arid and sub-tropical climate. Foliar spray showed a non-significant effect on water relations parameters. No significant interaction was found among stress levels and treatments. Stress levels showed significant differences in P concentration. Imposition of water stress significantly reduced the leaf K + concentration in contrast with boron foliar application which increased its concentration.The results showed that water stress and boron foliar application both significantly affected phosphorus contents. Stress levels were significantly varied in B concentration. Application of boron significantly affected the stem amylase activity in both S 1 and S 2 stress level and interaction among the stress levels and boron foliar application was non-significant. The effect of stress levels on stem amylase concentration was non-significant. A significant effect of boron foliar application was observed on stem protein concentration in all stress levelswhile interaction among the stress levels and boron foliar application was non-significant.The effect of stress levels on stem protein concentration was non-significant. Application of B significantly affected the stem total soluble sugars in both stress levels S 1 and S 2 while interaction among the stress levels and boron foliar application was non-significant
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