774 research outputs found

    A new MDA-SOA based framework for intercloud interoperability

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    Cloud computing has been one of the most important topics in Information Technology which aims to assure scalable and reliable on-demand services over the Internet. The expansion of the application scope of cloud services would require cooperation between clouds from different providers that have heterogeneous functionalities. This collaboration between different cloud vendors can provide better Quality of Services (QoS) at the lower price. However, current cloud systems have been developed without concerns of seamless cloud interconnection, and actually they do not support intercloud interoperability to enable collaboration between cloud service providers. Hence, the PhD work is motivated to address interoperability issue between cloud providers as a challenging research objective. This thesis proposes a new framework which supports inter-cloud interoperability in a heterogeneous computing resource cloud environment with the goal of dispatching the workload to the most effective clouds available at runtime. Analysing different methodologies that have been applied to resolve various problem scenarios related to interoperability lead us to exploit Model Driven Architecture (MDA) and Service Oriented Architecture (SOA) methods as appropriate approaches for our inter-cloud framework. Moreover, since distributing the operations in a cloud-based environment is a nondeterministic polynomial time (NP-complete) problem, a Genetic Algorithm (GA) based job scheduler proposed as a part of interoperability framework, offering workload migration with the best performance at the least cost. A new Agent Based Simulation (ABS) approach is proposed to model the inter-cloud environment with three types of agents: Cloud Subscriber agent, Cloud Provider agent, and Job agent. The ABS model is proposed to evaluate the proposed framework.Fundação para a Ciência e a Tecnologia (FCT) - (Referencia da bolsa: SFRH SFRH / BD / 33965 / 2009) and EC 7th Framework Programme under grant agreement n° FITMAN 604674 (http://www.fitman-fi.eu

    An Agent-Based Intrusion Detection System for Local Area Networks

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    Since it is impossible to predict and identify all the vulnerabilities of a network beforehand, and penetration into a system by malicious intruders cannot always be prevented, intrusion detection systems (IDSs) are essential entities to ensure the security of a networked system. To be effective in carrying out their functions, the IDSs need to be accurate, adaptive, and extensible. Given these stringent requirements and the high level of vulnerabilities of the current days' networks, the design of an IDS has become a very challenging task. Although, an extensive research has been done on intrusion detection in a distributed environment, distributed IDSs suffer from a number of drawbacks e.g., high rates of false positives, low detection efficiency etc. In this paper, the design of a distributed IDS is proposed that consists of a group of autonomous and cooperating agents. In addition to its ability to detect attacks, the system is capable of identifying and isolating compromised nodes in the network thereby introducing fault-tolerance in its operations. The experiments conducted on the system have shown that it has a high detection efficiency and low false positives compared to some of the currently existing systems.Comment: 13 pages, 5 figures, 2 table

    Consulting in computer systems and software

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    This report aims to describe the work I have done during my project in company. It is part of my second year in the Master of Computer Engineering – Mobile Computing of the School of Technology and Management of the Polytechnic Institute of Leiria. During this experience, I was assigned two missions. The first one is about the study of a S/MIME solution for email security and the second one is about the improvement of Microsoft Office 365 security score. For both missions I had material at my disposal and some instructions were given to me. I began by analysing the situation, and then established a state of the art in terms of technologies used. Then, thanks to my knowledge, I simulated virtual computer networks, tested encryption solutions, determined what were the best security practices, automated my work by scripting, reported the difficulties, and provided a detailed documentation about my work. The solutions produced respond to the problems, and they are functional. For the first mission, client machines can send S/MIME emails in a virtual network. For the second mission, the scripts and the tool provided allow to improve Microsoft Office 365 security score

    A Framework for Hybrid Intrusion Detection Systems

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    Web application security is a definite threat to the world’s information technology infrastructure. The Open Web Application Security Project (OWASP), generally defines web application security violations as unauthorized or unintentional exposure, disclosure, or loss of personal information. These breaches occur without the company’s knowledge and it often takes a while before the web application attack is revealed to the public, specifically because the security violations are fixed. Due to the need to protect their reputation, organizations have begun researching solutions to these problems. The most widely accepted solution is the use of an Intrusion Detection System (IDS). Such systems currently rely on either signatures of the attack used for the data breach or changes in the behavior patterns of the system to identify an intruder. These systems, either signature-based or anomaly-based, are readily understood by attackers. Issues arise when attacks are not noticed by an existing IDS because the attack does not fit the pre-defined attack signatures the IDS is implemented to discover. Despite current IDSs capabilities, little research has identified a method to detect all potential attacks on a system. This thesis intends to address this problem. A particular emphasis will be placed on detecting advanced attacks, such as those that take place at the application layer. These types of attacks are able to bypass existing IDSs, increase the potential for a web application security breach to occur and not be detected. In particular, the attacks under study are all web application layer attacks. Those included in this thesis are SQL injection, cross-site scripting, directory traversal and remote file inclusion. This work identifies common and existing data breach detection methods as well as the necessary improvements for IDS models. Ultimately, the proposed approach combines an anomaly detection technique measured by cross entropy and a signature-based attack detection framework utilizing genetic algorithm. The proposed hybrid model for data breach detection benefits organizations by increasing security measures and allowing attacks to be identified in less time and more efficiently

    An Approach to Guide Users Towards Less Revealing Internet Browsers

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    When browsing the Internet, HTTP headers enable both clients and servers send extra data in their requests or responses such as the User-Agent string. This string contains information related to the sender’s device, browser, and operating system. Previous research has shown that there are numerous privacy and security risks result from exposing sensitive information in the User-Agent string. For example, it enables device and browser fingerprinting and user tracking and identification. Our large analysis of thousands of User-Agent strings shows that browsers differ tremendously in the amount of information they include in their User-Agent strings. As such, our work aims at guiding users towards using less exposing browsers. In doing so, we propose to assign an exposure score to browsers based on the information they expose and vulnerability records. Thus, our contribution in this work is as follows: first, provide a full implementation that is ready to be deployed and used by users. Second, conduct a user study to identify the effectiveness and limitations of our proposed approach. Our implementation is based on using more than 52 thousand unique browsers. Our performance and validation analysis show that our solution is accurate and efficient. The source code and data set are publicly available and the solution has been deployed

    ANALYSIS OF DATA & COMPUTER NETWORKS IN STUDENTS' RESIDENTIAL AREA IN UNIVERSITI TEKNOLOGI PETRONAS

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    In Universiti Teknologi Petronas (UTP), most of the students depend on the Internet and computer network connection to gain academics information and share educational resources. Even though the Internet connections and computers networks are provided, the service always experience interruption, such as slow Internet access, viruses and worms distribution, and network abuse by irresponsible students. Since UTP organization keeps on expanding, the need for a better service in UTP increases. Several approaches were put into practice to address the problems. Research on data and computer network was performed to understand the network technology applied in UTP. A questionnaire forms were distributed among the students to obtain feedback and statistical data about UTP's network in Students' Residential Area. The studies concentrate only on Students' Residential Area as it is where most of the users reside. From the survey, it can be observed that 99% of the students access the network almost 24 hours a day. In 2005, the 2 Mbps allocated bandwidth was utilized 100% almost continuously but in 2006, the bottleneck of Internet access has reduced significantly since the bandwidth allocated have been increased to 8 Mbps. Server degradation due to irresponsible acts by users also adds burden to the main server. In general, if the proposal to ITMS (Information Technology & Media Services) Department for them to improve their Quality of Service (QoS) and established UTP Computer Emergency Response Team (UCert), most of the issues addressed in this report can be solved
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