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Wireless networks are continuing to grow around the world due to the advantages it offers and all the different services that it provides. In networking environments where the communication goes through a wireless connection, the importance of protecting the private information is a very significant task for network administrators. Beside the great benefits from having this type of network, the major issue of wireless communications is the weak security it provides. Companies and business organizations are more and more involved with the use of wireless networks because of the flexibility, mobility and the scalability it offers, but they are also concerned about the consequences of having a weaker security to protect their expensive investments and information. This thesis discusses the issues behind the security of wireless networks. It explains the background of the wireless networks and describes how the different security algorithms and encryptions work. The authors of this thesis decided to present some of the possible attacks that could occur in wireless networks and also give some security solutions to help others protect their network. The group that worked together on this project had the idea of investigating how secure the actual wireless algorithms and encryptions are. The approach of finding the necessary information for presenting the results and conclusions was to perform penetration tests on wireless networks that were implemented with the three famous security algorithms of WEP, WPA and WPA2. The penetrations tests were performed in lab environments and in home networks with the use of cracking tools. The group used the open source Linux based distribution called BackTrack 5. This operating system provided the group the different cracking tools that would help them perform their investigation. The purpose of performing the penetration tests was to find out the vulnerabilities that each of the security algorithms poses and therefore be able to determine which of them offers the best protection to a wireless network. After the penetration tests were done, the group came up with some solutions by configuring a wireless network with the strongest security options. The solutions were aimed to help others how to configure a specific wireless network in a simple but effective way. The results indicated that the weakest security algorithm would present some major issues for a wireless network. It included a greater possibility of experiencing different network attacks by configuring a wireless network with a weak security algorithm. Overall, this thesis provided the group the necessary information that was beneficial for them to understand how strong a wireless network actually is, and how a penetration test was performed.

This project is concerned with the security of Wi-Fi network. It defines security and introduces the principles of some security systems which are consequently instructed for its breakthrough, out of which follows the nature of security failures. The main emphasis is put on the current security issue of Wi-Fi Protected Setup (WPS) technology. Consequently, it is concerned with the putting into service of this technology in GNU/Linux distribution OpenWrt on Wi-Fi router TP-LINK TL-WR1043ND. The project is concluded with the suggestions for the correction of the security failure.

A set of elementary building blocks undergoes self-assembly if local interactions govern how this set forms intricate structures. Self-assembly has been widely observed in nature, ranging from the field of crystallography to the study of viruses and multicellular organisms. A natural question is whether a model of self-assembly can capture the hierarchical growth seen in nature or in other fields of mathematics. In this work, we consider hierarchical growth in substitution rules; informally, a substitution rule describes the iterated process by which the polygons of a given set are individually enlarged and dissected. We develop the Polygonal Two-Handed Assembly Model (p-2HAM) where building blocks, or tiles, are polygons and growth occurs when tiles bind to one another via matching, complementary bonds on adjacent sides; the resulting assemblies can then be used to construct new, larger structures. The p-2HAM is based on a handful of well-studied models, notably the Two-Handed Assembly Model and the polygonal free-body Tile Assembly Model. The primary focus of our work is to provide conditions which are either necessary or sufficient for the ``bordered simulation'' substitution rules. By this, we mean that a border made up of tiles is allowed to form around an assembly which then coordinates how the assembly interacts with other assemblies. In our main result, we provide a construction which gives a sufficient condition for bordered simulation. This condition is presented in graph theoretic terms and considers the adjacency of the polygons in the tilings associated to a given substitution rule. Alongside our results, we consider a collection of over one hundred substitution rules from various sources. We show that only the substitution rules in this collection which satisfy our sufficient condition admit bordered simulation. We conclude by considering open questions related to simulating substitution rules and to hierarchical growth in general.

<p>Denna rapporten är en jämförelse av forensiska verktyg, i detta fallet är verktygen EnCase och BackTrack. Vi kommer i den här rapporten att jämföra vissa utvalda verktyg som representeras i båda programmen, och analysera resultatet av detta. Analysen och jämförelsen kommer därefter ligga till grund för om man kan få fram lika bra resultat med ett open-source program som med ett program man betalar för. Vi kommer att utföra analysen genom att använda en bevisfil och utföra tester på den i både BackTrack och EnCase. Resultatet kommer att diskuteras och presenteras i denna rapport.För att få fram bästa möjliga resultat kommer vi även att intervjua vissa utvalda personer med erfarenhet utav att arbeta med dessa program, för att få fram deras synpunkter</p>

Internet security (Network security) is a big topic that is very important in our society communication system, but it is extremely dynamic and wide in scope. This is the reason that many companies and organizations invest heavily in a dedicated infrastructure security and highly trained specialists.The aim of security monitoring and preventing the network from cyber threats requires vigilance over the network equipment. The case study of this thesis is to provide the possible solution to the problems encountered by the namely network users such as: Internet Game Center (Centrum Halmstad, Sweden) and, the Blueville Internet Cafe (Ede, Nigeria).Our research and information collected over the telephone and a visit at the nearest office. We concluded that both companies mentioned above experienced similar cyber threats. The two companies have internal and external threats such as accessing the network via ssh by using it brute force attack, network war-driver, the installation of spyware, password sniffer, viruses, SQL injection and PHP attacks (web attacks) on the networks. The cyber threats virus and spyware are among the big internet threat to users, organization and companies.We carry out experiments in the lab to tests for threats such as brute force (ssh) attack, password sniffer and war-driver in the Wireless environment. From the results, we are able to the select WPA2 using 802.1x as the best possible way to limit and reduce the strength of cyber-attacks, and as a suggested solution to the namely café problems in our report. We also list different suggestion and solution to the cyber café attacks from our research papers and information gathers from different sources such as library, internet, seminar and textbooks.

The runtime for solving constraint satisfaction problems (CSP) and propositional satisfiability problems (SAT) using systematic backtracking search has been shown to exhibit great variability. Randomization and restarts is an effective technique for reducing such variability to achieve better expected performance. Several restart strategies have been proposed and studied in previous work and show differing degrees of empirical effectiveness. <br /><br /> The first topic in this thesis is the extension of analytical results on restart strategies through the introduction of physically based assumptions. In particular, we study the performance of two of the restart strategies on Pareto runtime distributions. We show that the geometric strategy provably removes heavy tail. We also examine several factors that arise during implementation and their effects on existing restart strategies. <br /><br /> The second topic concerns the development of a new hybrid restart strategy in a realistic problem setting. Our work adapts the existing general approach on dynamic strategy but implements more sophisticated machine learning techniques. The resulting hybrid strategy shows superior performance compared to existing static strategies and an improved robustness.

The runtime for solving constraint satisfaction problems (CSP) and propositional satisfiability problems (SAT) using systematic backtracking search has been shown to exhibit great variability. Randomization and restarts is an effective technique for reducing such variability to achieve better expected performance. Several restart strategies have been proposed and studied in previous work and show differing degrees of empirical effectiveness. <br /><br /> The first topic in this thesis is the extension of analytical results on restart strategies through the introduction of physically based assumptions. In particular, we study the performance of two of the restart strategies on Pareto runtime distributions. We show that the geometric strategy provably removes heavy tail. We also examine several factors that arise during implementation and their effects on existing restart strategies. <br /><br /> The second topic concerns the development of a new hybrid restart strategy in a realistic problem setting. Our work adapts the existing general approach on dynamic strategy but implements more sophisticated machine learning techniques. The resulting hybrid strategy shows superior performance compared to existing static strategies and an improved robustness.

Thesis (M.S.)--University of Colorado, 2000. / Includes bibliographical references (leaf 62).

Denna rapporten är en jämförelse av forensiska verktyg, i detta fallet är verktygen EnCase och BackTrack. Vi kommer i den här rapporten att jämföra vissa utvalda verktyg som representeras i båda programmen, och analysera resultatet av detta. Analysen och jämförelsen kommer därefter ligga till grund för om man kan få fram lika bra resultat med ett open-source program som med ett program man betalar för. Vi kommer att utföra analysen genom att använda en bevisfil och utföra tester på den i både BackTrack och EnCase. Resultatet kommer att diskuteras och presenteras i denna rapport.För att få fram bästa möjliga resultat kommer vi även att intervjua vissa utvalda personer med erfarenhet utav att arbeta med dessa program, för att få fram deras synpunkter