3,100 research outputs found
Reinforcement learning for efficient network penetration testing
Penetration testing (also known as pentesting or PT) is a common practice for actively assessing the defenses of a computer network by planning and executing all possible attacks to discover and exploit existing vulnerabilities. Current penetration testing methods are increasingly becoming non-standard, composite and resource-consuming despite the use of evolving tools. In this paper, we propose and evaluate an AI-based pentesting system which makes use of machine learning techniques, namely reinforcement learning (RL) to learn and reproduce average and complex pentesting activities. The proposed system is named Intelligent Automated Penetration Testing System (IAPTS) consisting of a module that integrates with industrial PT frameworks to enable them to capture information, learn from experience, and reproduce tests in future similar testing cases. IAPTS aims to save human resources while producing much-enhanced results in terms of time consumption, reliability and frequency of testing. IAPTS takes the approach of modeling PT environments and tasks as a partially observed Markov decision process (POMDP) problem which is solved by POMDP-solver. Although the scope of this paper is limited to network infrastructures PT planning and not the entire practice, the obtained results support the hypothesis that RL can enhance PT beyond the capabilities of any human PT expert in terms of time consumed, covered attacking vectors, accuracy and reliability of the outputs. In addition, this work tackles the complex problem of expertise capturing and re-use by allowing the IAPTS learning module to store and re-use PT policies in the same way that a human PT expert would learn but in a more efficient way
Piggybacking Codes for Network Coding: The High/Low SNR Regime
We propose a piggybacking scheme for network coding where strong source
inputs piggyback the weaker ones, a scheme necessary and sufficient to achieve
the cut-set upper bound at high/low-snr regime, a new asymptotically optimal
operational regime for the multihop Amplify and Forward (AF) networks
Network Coding: Connections Between Information Theory And Estimation Theory
In this paper, we prove the existence of fundamental relations between
information theory and estimation theory for network-coded flows. When the
network is represented by a directed graph G=(V, E) and under the assumption of
uncorrelated noise over information flows between the directed links connecting
transmitters, switches (relays), and receivers. We unveil that there yet exist
closed-form relations for the gradient of the mutual information with respect
to different components of the system matrix M. On the one hand, this result
opens a new class of problems casting further insights into effects of the
network topology, topological changes when nodes are mobile, and the impact of
errors and delays in certain links into the network capacity which can be
further studied in scenarios where one source multi-sinks multicasts and
multi-source multicast where the invertibility and the rank of matrix M plays a
significant role in the decoding process and therefore, on the network
capacity. On the other hand, it opens further research questions of finding
precoding solutions adapted to the network level.Comment: IEEE Wireless Communications and Networking Conference (WCNC), April,
201
Grid-enabled Workflows for Industrial Product Design
This paper presents a generic approach for developing and using Grid-based workflow technology for enabling cross-organizational engineering applications. Using industrial product design examples from the automotive and aerospace industries we highlight the main requirements and challenges addressed by our approach and describe how it can be used for enabling interoperability between heterogeneous workflow engines
ETHICAL LEADERSHIP IN EDUCATION AND ITS RELATION TO EDUCATION MANAGEMENT ETHICS
This study relied on examining the relevant literature, and researchers’ opinion on ethical leadership in education and its relation to education management ethics, as management ethics is defined as a behavior rules of the school principals in management activities in day to day bases, taking into consideration that school teachers and principals are obliged to obey to the rules and regulation with regards to culture and tradition of what’s good and what’s bad in line with ethics principles, considering schools’ principals are honest and fair in their behavior, and everyone in the school should be treated equally. Ethical leadership is characterized with ethics values in the management function as to decision making, behavioral ethics, communication, coordination, leading, planning and organizing, thus the ethical values that ethical leadership have in playing a leadership role also play a great role in the institutions, and the values that education principals have are determined by determining educational policies and philosophy, trying to implement these policies through oriented programs, selecting, developing and evaluating staff, rational use of resources, creating a healthy school culture. Article visualizations
Investigating the Allosteric Behavior of Malate Dehydrogenase from Escherichia coli
Regulatory mechanisms of malate dehydrogenase from E.coli (eMDH) involving NADH as an allosteric effector were investigated. The reaction was studied in both directions: malate oxidation and oxaloacetate reduction. When malate was the variable substrate, a plot of rate against substrate concentration was sigmoidal in the presence of 0.065 mM NADH, which indicates the presence of an allosteric site for NADH on the enzyme. Binding of NADH at the allosteric site causes conformational changes in the active site and, thereby, changes the catalytic activity of the enzyme. An increase in Km value, from 1.3 to 3.9 mM malate was observed, which indicates a decrease in the enzyme affinity for the substrate.
When eMDH was chemically modified with 5\u27-p-flurosulfonyl-benzoyladenosine (FSBA) in the presence of 0.15 mM NADH as a protecting agent, the allosteric behavior was abolished, which suggests that FSBA is modifying specific amino acid residues in the allosteric site and, therefore, preventing NADH from binding. eMDH was inactivated by FSBA in the absence of NADH. The inactivation appears to result from covalent modification of His 177 in the active site, which is believed to be crucial for the catalytic mechanism of eMDH
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