1,389 research outputs found
Study on Intrusion Detection System for a Campus Network
All final year students in UTP are required to undertake a final year project (FYP)
paper, which are a design and/or research-based subject. It requires student to do
research; design and/or development work in each discipline, especially on realworld
problems which would motivate student to produce practical solutions. This
project title is "Study on Intrusion Detection System for a Campus Network". It is a
research and development work project. The objective of the project is to make sure
student do a research in the area that relevant with specified title. Beside, student
also needs to make a test bed application that is used in implementing the IDS. This
project scope will focus on implementing the IDS in campus network and how to
simulate the attacks besides measure it effectiveness in detecting any intrusion
Online Accumulation: Reconstruction of Worm Propagation Path
Abstract. Knowledge of the worm origin is necessary to forensic analysis, and knowledge of the initial causal flows supports diagnosis of how network defenses were breached. Fast and accurate online tracing network worm during its propagation, help to detect worm origin and the earliest infected nodes, and is essential for large-scale worm containment. This paper introduces the Accumulation Algorithm which can efficiently tracing worm origin and the initial propagation paths, and presents an improved online Accumulation Algorithm using sliding detection windows. We also analyzes and verifies their detection accuracy and containment efficacy through simulation experiments in large scale network. Results indicate that the online Accumulation Algorithm can accurately tracing worms and efficiently containing their propagation in an approximately real-time manner
Genomic introgression mapping of field-derived multiple-anthelmintic resistance in Teladorsagia circumcincta
Preventive chemotherapy has long been practiced against nematode parasites of livestock, leading to widespread drug resistance, and is increasingly being adopted for eradication of human parasitic nematodes even though it is similarly likely to lead to drug resistance. Given that the genetic architecture of resistance is poorly understood for any nematode, we have analyzed multidrug resistant Teladorsagia circumcincta, a major parasite of sheep, as a model for analysis of resistance selection. We introgressed a field-derived multiresistant genotype into a partially inbred susceptible genetic background (through repeated backcrossing and drug selection) and performed genome-wide scans in the backcross progeny and drug-selected F2 populations to identify the major genes responsible for the multidrug resistance. We identified variation linking candidate resistance genes to each drug class. Putative mechanisms included target site polymorphism, changes in likely regulatory regions and copy number variation in efflux transporters. This work elucidates the genetic architecture of multiple anthelmintic resistance in a parasitic nematode for the first time and establishes a framework for future studies of anthelmintic resistance in nematode parasites of humans
Deteção de propagação de ameaças e exfiltração de dados em redes empresariais
Modern corporations face nowadays multiple threats within their networks. In an era where companies are tightly dependent on information, these threats can seriously compromise the safety and integrity of sensitive data. Unauthorized access and illicit programs comprise a way of penetrating the corporate networks, able to traversing and propagating to other terminals across the private network, in search of confidential data and business secrets. The efficiency of traditional security defenses are being questioned with the number of data breaches occurred nowadays, being essential the development of new active monitoring systems with artificial intelligence capable to achieve almost perfect detection in very short time frames. However, network monitoring and storage of network activity records are restricted and limited by legal laws
and privacy strategies, like encryption, aiming to protect the confidentiality of private parties. This dissertation proposes methodologies to infer behavior patterns and disclose anomalies from network traffic analysis, detecting slight variations compared with the normal profile. Bounded by network OSI layers 1 to 4, raw data are modeled in features, representing network observations, and posteriorly, processed by machine learning algorithms to classify network activity. Assuming the inevitability of a network terminal to be compromised, this work comprises two scenarios: a self-spreading force that propagates over internal network and a data exfiltration charge which dispatch confidential info to the public network. Although features and modeling processes have been tested for these two cases, it is a generic operation that can be used in
more complex scenarios as well as in different domains. The last chapter describes the proof of concept scenario and how data was generated, along with some evaluation metrics to perceive the model’s performance. The tests manifested promising results, ranging from 96% to 99% for the propagation case and 86% to 97% regarding data exfiltration.Nos dias de hoje, várias organizações enfrentam múltiplas ameaças no interior da sua rede. Numa época onde as empresas dependem cada vez mais da
informação, estas ameaças podem compremeter seriamente a segurança e a integridade de dados confidenciais. O acesso não autorizado e o uso de programas ilÃcitos constituem uma forma de penetrar e ultrapassar as barreiras organizacionais, sendo capazes de propagarem-se para outros terminais presentes no interior da rede privada com o intuito de atingir dados confidenciais e segredos comerciais. A eficiência da segurança oferecida pelos sistemas de defesa tradicionais está a ser posta em causa devido ao elevado número de ataques de divulgação de dados sofridos pelas empresas. Desta forma, o desenvolvimento de novos sistemas de monitorização ativos usando inteligência artificial é crucial na medida de atingir uma deteção mais precisa em curtos perÃodos de tempo. No entanto, a monitorização e o armazenamento dos registos da atividade da rede são restritos e limitados por questões legais e estratégias de privacidade, como a cifra dos dados, visando proteger a confidencialidade das entidades. Esta dissertação propõe metodologias para inferir padrões de comportamento e revelar anomalias através da análise de
tráfego que passa na rede, detetando pequenas variações em comparação com o perfil normal de atividade. Delimitado pelas camadas de rede OSI 1
a 4, os dados em bruto são modelados em features, representando observações de rede e, posteriormente, processados por algoritmos de machine learning para classificar a atividade de rede. Assumindo a inevitabilidade de um terminal ser comprometido, este trabalho compreende dois cenários: um ataque que se auto-propaga sobre a rede interna e uma tentativa de exfiltração de dados que envia informações para a rede pública. Embora os processos de criação de features e de modelação tenham sido testados para estes dois casos, é uma operação genérica que pode ser utilizada em cenários mais complexos, bem como em domÃnios diferentes. O último capÃtulo inclui uma prova de conceito e descreve o método de criação dos dados, com a utilização de algumas métricas de avaliação de forma a espelhar a performance do modelo. Os testes mostraram resultados promissores, variando entre 96% e 99% para o caso da propagação e entre 86% e 97% relativamente ao roubo de dados.Mestrado em Engenharia de Computadores e Telemátic
On the Adaptive Real-Time Detection of Fast-Propagating Network Worms
We present two light-weight worm detection algorithms thatoffer significant advantages over fixed-threshold methods.The first algorithm, RBS (rate-based sequential hypothesis testing)aims at the large class of worms that attempts to quickly propagate, thusexhibiting abnormal levels of the rate at which hosts initiateconnections to new destinations. The foundation of RBS derives fromthe theory of sequential hypothesis testing, the use of which fordetecting randomly scanning hosts was first introduced by our previouswork with the TRW (Threshold Random Walk) scan detection algorithm. The sequential hypothesistesting methodology enables engineering the detectors to meet falsepositives and false negatives targets, rather than triggering whenfixed thresholds are crossed. In this sense, the detectors that weintroduce are truly adaptive.We then introduce RBS+TRW, an algorithm that combines fan-out rate (RBS)and probability of failure (TRW) of connections to new destinations.RBS+TRW provides a unified framework that at one end acts as a pure RBSand at the other end as pure TRW, and extends RBS's power in detectingworms that scan randomly selected IP addresses
A Network-Aware Distributed Membership Protocol for Collaborative Defense
To counteract current trends in network malware, distributed solutions have been developed that harness the power of collaborative end-host sensors. While these systems greatly increase the ability to defend against attack, this comes at the cost of complexity due to the coordination of distributed hosts across the dynamic network. Many previous solutions for distributed membership maintenance are agnostic to network conditions and have high overhead, making them less than ideal in the dynamic enterprise environment. In this work, we propose a network-aware, distributed membership protocol, CLUSTER, which improves the performance of the overlay system by biasing neighbor selection towards beneficial nodes based on multiple system metrics and network social patterns (of devices and their users). We provide an extensible method for aggregating and comparing multiple, possibly unrelated metrics. We demonstrate the effectiveness and utility of our protocol through simulation using real-world data and topologies. As part of our results, we highlight our analysis of node churn statistics, offering a new distribution to accurately model enterprise churn
Anagram: A Content Anomaly Detector Resistant to Mimicry Attack
In this paper, we present Anagram, a content anomaly detector that models a mixture of high-order n-grams (n > 1) designed to detect anomalous and suspicious network packet payloads. By using higher- order n-grams, Anagram can detect significant anomalous byte sequences and generate robust signatures of validated malicious packet content. The Anagram content models are implemented using highly efficient Bloom filters, reducing space requirements and enabling privacy-preserving cross-site correlation. The sensor models the distinct content flow of a network or host using a semi- supervised training regimen. Previously known exploits, extracted from the signatures of an IDS, are likewise modeled in a Bloom filter and are used during training as well as detection time. We demonstrate that Anagram can identify anomalous traffic with high accuracy and low false positive rates. Anagram’s high-order n-gram analysis technique is also resilient against simple mimicry attacks that blend exploits with normal appearing byte padding, such as the blended polymorphic attack recently demonstrated in. We discuss randomized n-gram models, which further raises the bar and makes it more difficult for attackers to build precise packet structures to evade Anagram even if they know the distribution of the local site content flow. Finally, Anagram-’s speed and high detection rate makes it valuable not only as a standalone sensor, but also as a network anomaly flow classifier in an instrumented fault-tolerant host-based environment; this enables significant cost amortization and the possibility of a symbiotic feedback loop that can improve accuracy and reduce false positive rates over time
On countermeasures of worm attacks over the Internet
Worm attacks have always been considered dangerous threats to the Internet since they can
infect a large number of computers and consequently cause large-scale service disruptions and
damage. Thus, research on modeling worm attacks, and defenses against them, have become
vital to the field of computer and network security. This dissertation intends to systematically
study two classes of countermeasures against worm attacks, known as traffic-based
countermeasure and non-traffic based countermeasure. Traffic-based countermeasures are those
whose means are limited to monitoring, collecting, and analyzing the traffic generated by worm
attacks. Non-traffic based countermeasures do not have such limitations.
For the traffic-based countermeasures, we first consider the worm attack that adopts feedback
loop-control mechanisms which make its overall propagation traffic behavior similar to
background non-worm traffic and circumvent the detection. We also develop a novel spectrumbased
scheme to achieve highly effective detection performance against such attacks. We then
consider worm attacks that perform probing traffic in a stealthy manner to obtain the location infrastructure of a defense system and introduce an information-theoretic based framework to
obtain the limitations of such attacks and develop corresponding countermeasures.
For the non-traffic based countermeasures, we first consider new unseen worm attacks and
develop the countermeasure based on mining the dynamic signature of worm programs’ run-time
execution. We then consider a generic worm attack that dynamically changes its propagation
patterns and develops integrated countermeasures based on the attacker’s contradicted
objectives. Lastly, we consider the real-world system setting with multiple incoming worm
attacks that collaborate by sharing the history of their interactions with the defender and develop
a generic countermeasure based on establishing the defender’s reputation of toughness in its
repeated interactions with multiple incoming attackers to optimize the long-term defense
performance.
This dissertation research has broad impacts on Internet worm research since this work is
fundamental, practical and extensible. Our developed framework can be used by researchers to
understand key features of other forms of new worm attacks and develop countermeasures
against them
Systems biology studies of adult Paragonimus lung flukes facilitate the identification of immunodominant parasite antigens
Paragonimiasis is a food-borne trematode infection acquired by eating raw or undercooked crustaceans. It is a major public health problem in the far East, but it also occurs in South Asia, Africa, and in the Americas. Paragonimus worms cause chronic lung disease with cough, fever and hemoptysis that can be confused with tuberculosis or other non-parasitic diseases. Treatment is straightforward, but diagnosis is often delayed due to a lack of reliable parasitological or serodiagnostic tests. Hence, the purpose of this study was to use a systems biology approach to identify key parasite proteins that may be useful for development of improved diagnostic tests.The transcriptome of adult Paragonimus kellicotti was sequenced with Illumina technology. Raw reads were pre-processed and assembled into 78,674 unique transcripts derived from 54,622 genetic loci, and 77,123 unique protein translations were predicted. A total of 2,555 predicted proteins (from 1,863 genetic loci) were verified by mass spectrometric analysis of total worm homogenate, including 63 proteins lacking homology to previously characterized sequences. Parasite proteins encoded by 321 transcripts (227 genetic loci) were reactive with antibodies from infected patients, as demonstrated by immunoaffinity purification and high-resolution liquid chromatography-mass spectrometry. Serodiagnostic candidates were prioritized based on several criteria, especially low conservation with proteins in other trematodes. Cysteine proteases, MFP6 proteins and myoglobins were abundant among the immunoreactive proteins, and these warrant further study as diagnostic candidates.The transcriptome, proteome and immunolome of adult P. kellicotti represent a major advance in the study of Paragonimus species. These data provide a powerful foundation for translational research to develop improved diagnostic tests. Similar integrated approaches may be useful for identifying novel targets for drugs and vaccines in the future
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