11 research outputs found

    Preventing Distributed Denial-of-Service Attacks on the IMS Emergency Services Support through Adaptive Firewall Pinholing

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    Emergency services are vital services that Next Generation Networks (NGNs) have to provide. As the IP Multimedia Subsystem (IMS) is in the heart of NGNs, 3GPP has carried the burden of specifying a standardized IMS-based emergency services framework. Unfortunately, like any other IP-based standards, the IMS-based emergency service framework is prone to Distributed Denial of Service (DDoS) attacks. We propose in this work, a simple but efficient solution that can prevent certain types of such attacks by creating firewall pinholes that regular clients will surely be able to pass in contrast to the attackers clients. Our solution was implemented, tested in an appropriate testbed, and its efficiency was proven.Comment: 17 Pages, IJNGN Journa

    Traffic generator for firewall testing

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    Thesis (Master)--Izmir Institute of Technology, Computer Engineering, Izmir, 2009Includes bibliographical references (leaves: 52-56)Text in English; Abstract: Turkish and Englishix, 92 leavesFirewalls lead at the front line of a computer network to restrict unauthorized access. The desired security level is determined by a policy and implemented by a firewall which not only has to be effective but also stable and reliable service is expected. In order to verify the level of security of the system, testing is required. The objective of this thesis is to test a firewall with software testing techniques taking into consideration the nominated policy and the firewall. Iptables software was examined and tested by two different algorithms that were modified according to software testing techniques, and the results were observed. Packets sent through the Firewall Under Test (FUT) are compared to packets passed through the FUT and test results were observed. The security performance of the modified algorithms proved to be successful

    Formal analysis of firewall policies

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    This dissertation describes a technique for formally analyzing a firewall security policy using a quasi-reduced multiway decision diagram model. The analysis allows a system administrator to detect and repair errors in the configuration of the firewall without a tedious manual inspection of the firewall rules.;We present four major contributions. First, we describe a set of algorithms for representing a firewall rule set as a multi-way decision diagram and for solving logical queries against that model. We demonstrate the application of these techniques in a tool for analyzing iptables firewalls. Second, we present an extension of our work that enables analysis of systems of connected firewalls and firewalls that use network address translation and other packet mangling rules. Third, we demonstrate a technique for decomposing a network into classes of equivalent hosts. These classes can be used to detect errors in a firewall policy without apriori knowledge of potential vulnerabilities. They can also be used with other firewall testing techniques to ensure comprehensive coverage of the test space. Fourth, we discuss a strategy for partially automating repair of the firewall policy through the use of counterexamples and rule history.;Using these techniques, a system administrator can detect and repair common firewall errors, such as typos, out-of-order rules, and shadowed rules. She can also develop a specification of the behaviors of the firewall and validate the firewall policy against that specification

    Bearicade: A Novel High-Performance Computing User and Security Management System Augmented with Machine Learning Technology

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    Despite the rising development and popularity of HPC systems, there have been insufficient advancements towards the security of HPC systems. The substantial computational power, high bandwidth networks, and massive storage capacity provided in the HPC environment are desirable targets for the attackers. The majority of educational institution HPC centres provide their users with simple access methods lacking the modern security needs. Thus, accelerating the systems’ proneness to modern cyber-attacks. The current implementations of HPC access points, such as web portals, offer users direct access to the HPC systems. Consequently, such web portal implementations affect the HPC system with the same security challenges faced by cloud providers and web applications. Although attempts have been made toward securing HPC systems, most of these implementations are outdated, insufficient with the current security standards, or do not integrate well with modern HPC access solutions. To address these security issues, Bearicade, a novel High-Performance Computing (HPC) user and security management system, was designed, developed, implemented and evaluated. Bearicade is a data-driven secure unified framework for managing HPC users and systems security. This framework is an add-on layer to an existing HPC systems software, collecting over 50 different types of information from multiple sources within the HPC systems. It offers Artificial Intelligent security solutions with an added usability and accessibility without adversely affecting the performance and functionality of HPC systems. Throughout this study, the security and usability of Bearicade were validated implementing multiple Machine Learning models. It has been deployed over three years as a production system for students and researchers at the University of Huddersfield QueensGate Grid (QGG) with considerable success, protecting the QGG systems from the summer 2020 attacks that has affected many other HPC systems in research and educational establishments

    Virtual time-aware virtual machine systems

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    Discrete dynamic system models that track, maintain, utilize, and evolve virtual time are referred to as virtual time systems (VTS). The realization of VTS using virtual machine (VM) technology offers several benefits including fidelity, scalability, interoperability, fault tolerance and load balancing. The usage of VTS with VMs appears in two ways: (a) VMs within VTS, and (b) VTS over VMs. The former is prevalent in high-fidelity cyber infrastructure simulations and cyber-physical system simulations, wherein VMs form a crucial component of VTS. The latter appears in the popular Cloud computing services, where VMs are offered as computing commodities and the VTS utilizes VMs as parallel execution platforms. Prior to our work presented here, the simulation community using VM within VTS (specifically, cyber infrastructure simulations) had little awareness of the existence of a fundamental virtual time-ordering problem. The correctness problem was largely unnoticed and unaddressed because of the unrecognized effects of fair-share multiplexing of VMs to realize virtual time evolution of VMs within VTS. The dissertation research reported here demonstrated the latent incorrectness of existing methods, defined key correctness benchmarks, quantitatively measured the incorrectness, proposed and implemented novel algorithms to overcome incorrectness, and optimized the solutions to execute without a performance penalty. In fact our novel, correctness-enforcing design yields better runtime performance than the traditional (incorrect) methods. Similarly, the VTS execution over VM platforms such as Cloud computing services incurs large performance degradation, which was not known until our research uncovered the fundamental mismatch between the scheduling needs of VTS execution and those of traditional parallel workloads. Consequently, we designed a novel VTS-aware hypervisor scheduler and showed significant performance gains in VTS execution over VM platforms. Prior to our work, the performance concern of VTS over VM was largely unaddressed due to the absence of an understanding of execution policy mismatch between VMs and VTS applications. VTS follows virtual-time order execution whereas the conventional VM execution follows fair-share policy. Our research quantitatively uncovered the exact cause of poor performance of VTS in VM platforms. Moreover, we proposed and implemented a novel virtual time-aware execution methodology that relieves the degradation and provides over an order of magnitude faster execution than the traditional virtual time-unaware execution.Ph.D

    Firewall Traversal in Mobile IPv6 Networks

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    Middleboxes, wie zum Beispiel Firewalls, sind ein wichtiger Aspekt für eine Großzahl moderner IP-Netzwerke. Heute IP-Netzwerke basieren überwiegend auf IPv4 Technologien, daher sind viele Firewalls und Network Address Translators (NATs) ursprünglich für diese Netzwerke entwickelt worden. Die Entwicklung von IPv6 Netzwerken findet zur Zeit statt. Da Mobile IPv6 ein relativ neuer Standard ist, unterstützen die meisten Firewalls die für IPv6 Netzwerke verfügbar sind, noch kein Mobile IPv6. Sofern Firewalls sich nicht der Details des Mobile IPv6 Protokolls bewusst sind, werden sie entweder Mobile IPv6 Kommunikation blockieren oder diesen sorgfältig handhaben. Dieses stellt einen der Haupthinderunggründe zum erfolgreichen Einsatz von Mobile IPv6 da.Diese Arbeit beschreibt die Probleme und Auswirkungen des Vorhandenseins von Middleboxes in Mobile IPv6 Umgebungen. Dazu wird zuerst erklärt welche Arten von Middleboxes es gibt, was genau eine Middlebox ist und wie eine solche Middlebox arbeiten und zweitens die Probleme identifiziert und die Auswirkungen des Vorhandenseins von Firewalls in Mobile IPv6 Umgebungen erklärt. Anschließend werden einige State-of-the-Art Middlebox Traversal Ansätze untersucht, die als mögliche Lösungen um die Mobile IPv6 Firewall Traversal Probleme zu bewältigen betrachtet werden können. Es wird detailiert erklärt wie diese Lösungen arbeiten und ihre Anwendbarkeit für Mobile IPv6 Firewall Traversal evaluiert.Als Hauptbeitrag bringt diese Arbeit zwei detailierte Lösungsansätze ein, welche das Mobile IPv6 Firewall Traversal Problem bewältigen können. Der erste Lösungsansatz, der NSIS basierte Mobile IPv6 Firewall Traversal, basiert auf dem Next Steps in Signaling (NSIS) Rahmenwerk und dem NAT/Firewall NSIS Signaling Layer Protocol (NAT/FW NSLP). Anschließend wird der zweite Lösungsansatz vorgestellt, der Mobile IPv6 Application Layer Gateway. Diese Arbeit erklärt detailiert, wie diese Lösungsansätze die Probleme und Auswirkungen des Vorhandenseins von Middleboxes in Mobile IPv6 Umgebungen bewältigen. Desweitern stellt diese Arbeit vor, wie die NSIS basierte Mobile IPv6 Firewall Traversal und die Mobile IPv6 Application Layer Gateway Proof-of-Concept Implementierungen, die im Rahmen dieser Arbeit entwicklet wurden, implementiert wurden. Abschließend werden die Proof-of-Concept Implementierungen sowie die beiden Lösungsansätze allgemein evaluiert und analysiert
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