1,999 research outputs found

    Modelling & Improving Flow Establishment in RSVP

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    RSVP has developed as a key component for the evolving Internet, and in particular for the Integrated Services Architecture. Therefore, RSVP performance is crucially important; yet this has been little studied up till now. In this paper, we target one of the most important aspects of RSVP: its ability to establish flows. We first identify the factors influencing the performance of the protocol by modelling the establishment mechanism. Then, we propose a Fast Establishment Mechanism (FEM) aimed at speeding up the set-up procedure in RSVP. We analyse FEM by means of simulation, and show that it offers improvements to the performance of RSVP over a range of likely circumstances

    Transition to High-Speed Networks — SuperJANET Experience

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    For the time being, trials to establish the Information Superhighway are booming. In Britain, JANET has provided wide-area computer communication, and has recently been upgraded to SuperJANET, increasing the throughput by a factor of five to 10 Mb/s, with some sites having PDH access at n × 34 Mb/s. In this paper, the technological changes seen from a user perspective are addressed. A multimedia communication-based distance learning project on SuperJANET is introduced and the network performance measurements for this project are presented. These measurements suggest the employment of reservation protocol and packet scheduling. We also provide a mechanism for on-the-fly playback of continuous media

    REDO RSVP: Efficient Signalling for Multimedia in the Internet

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    Alarming reports of performance and scalability problems associated with per-flow reservations, have led many to lose belief in RSVP and the Integrated Services Architecture that relies on it. Because we are convinced of the need for some form of resource reservation, to support multimedia communications in the Internet, we have set about trying to improve RSVP. By careful study of the protocol, we have identified areas for improvement, and propose REDO RSVP, a reduced overhead version that includes a fast establishment mechanism (FEM). In this paper we describe the rationale for REDO RSVP and present a detailed analysis of its features and operations. We also analyse REDO RSVP by means of simulations, and show that it offers improvements to the performance of RSVP

    The Vulnerability Assessment and Penetration Testing of Two Networks

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    Vulnerability assessments and penetration testing are two approaches available for use by internet security practitioners to determine the security posture of information networks. By assessing network vulnerabilities and attempting to exploit found vulnerabilities through penetration testing security professionals are able to evaluate the effectiveness of their network defenses by identifying defense weaknesses, affirming the defense mechanisms in place, or some combination of the two. This project is a discussion of the methods and tools used during the vulnerability assessment and penetration testing, and the respective test results of two varied and unique networks. The assessment and testing of the first network occurred from an internal perspective, while the assessment and testing of the second occurred from an external perspective. While the tools and methodologies used across both networks were consistent, the test results differed significantly. The paper concludes with a series of recommendations regarding practical methods and tools that may prove useful to anyone interested in network security, and vulnerability assessments and penetration testing in particular

    Effect of 2007-2009 Economic Crisis and Dodd-Frank Legislation on the U.S. Banking Industry

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    This correlation research study was used to investigate the impact of the Dodd-Frank legislation on the U.S. bank industry. The economic crisis of 2007-2009 had a global and significant financial impact, some of which still reverberates. In the United States, the reaction was The Dodd-Frank Wall Street Reform and Consumer Protection Act, which took effect July 21, 2010. This act has recently been the subject of academic research and remains debated in congress, with discussion focused on its repeal. The publicly available, secondary data set from banks\u27 quarterly filed regulatory reporting provided the data used in this study. Every FDIC insured bank in the United States was included in the study. The research question for the study examined the unintended consequences of Dodd-Frank legislation as posited by the theories of Bexley (2014) and Barth, Prabha, and Swagel (2012) that Dodd-Frank was a regulatory overreaction and could have a long-term impact on a substantial number of financial institutions. From 2007 through 2013, the number of banks declined by over 1,753 institutions; a 19.82% decline. The structure of the research presumed that banks that relied heavily on consumer fees for depository services would be negatively impacted by rule changes and regulation regarding such fees. There were two research questions. The first focused on the role of the new rules in the decline of the number of banks. The second explored the role of the legislation in the financial performance of banks. Regression results resulted in not being able to reject the null hypotheses. The implication of the study for social change is that policy makers who understand these relationships may construct better regulation to mitigate unfair and deceptive consumer fees for banking services

    Judicial Abdication and the Rise of Special Interests

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    Representations of the fundamental group of a surface in PU(p,q) and holomorphic triples

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    We count the connected components in the moduli space of PU(p,q)-representations of the fundamental group for a closed oriented surface. The components are labelled by pairs of integers which arise as topological invariants of the flat bundles associated to the representations. Our results show that for each allowed value of these invariants, which are bounded by a Milnor-Wood type inequality, there is a unique non-empty connected component. Interpreting the moduli space of representations as a moduli space of Higgs bundles, we take a Morse theoretic approach using a certain smooth proper function on the Higgs moduli space. A key step is the identification of the function's local minima as moduli spaces of holomorphic triples. We prove that these moduli spaces of triples are non-empty and irreducible.Comment: 6 pages, to appear in C. R. Acad. Sci. Paris Ser. I Mat