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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

State-of-the-art Study and Design of a Small Footprint Version of the COOS Plugin Framework

Khan, Kashif Nizam January 2010 (has links)
GSM and UMTS technologies have already gained a huge market penetrationresulting in millions of customers. Machine-to-Machine (M2M) Communicationis promising to be the next big technology that is going to hit themass market with numerous essential services. Telemetry systems, whichwere thought once as the domain of big industrial companies, are now beingavailable to larger and wider customers because of the advances in M2Mcommunication. Thanks to mobile technologies, millions of small handhelddevices are now available in the mass market which can be used to communicatereal time information to the customers. Telenor Objects (a smallbusiness unit of Telenor Group) has defined a new Connected Object Operatingsystem (COOS) which aims to provide a common platform for thedevices to communicate real time data and to provide value added servicesto the customers. COOS is a modular and flexible platform, and includes aplugin framework offered to device and service developers for easy connectingservices and devices to the platform. The current version of COOS pluginframework is based on Java Standard Edition and OSGI, with some supportfor development on J2ME. This thesis research work aims to provide a briefoverview of the Connected Object concept and the COOS platform architecture.The main goal of this thesis is to design a small footprint version ofthe COOS plugin framework for Windows-based handheld devices. It willalso provide a state-of- the art study on mobile device programming focusingon Windows-based services. This thesis research can serve as a startingdocument to provide a full functioning plugin framework for Windows-baseddevices and services.
92

Model Driven Development of Web Application with SPACE Method and Tool-suit

Rehana, Jinat January 2010 (has links)
Enterprise level software development using traditional software engineeringapproaches with third-generation programming languages is becoming morechallenging and cumbersome task with the increased complexity of products,shortened development cycles and heightened expectations of quality. MDD(Model Driven Development) has been counting as an exciting and magicaldevelopment approach in the software industry from several years. The ideabehind MDD is the separation of business logic of a system from its implementationdetails expressing problem domain using models. This separation andmodeling of problem domain simplify the process of system design as well asincrease the longevity of products as new technologies can be adopted easily.With appropriate tool support, MDD shortens the software development lifecycle drastically by automating a significant portion of development steps.MDA (Model Driven Architecture) is a framework launched by OMG (ObjectManagement Group) to support MDD. SPACE is an engineering methodfor rapid creation of services, developed at NTNU (Norwegian University ofScience and Technology) which follows MDA framework. Arctis and Ramsesare tool suits, also developed at NTNU to support SPACE method. Severalsolutions have been developed on Arctis tool suit covering several domainslike mobile services, embedded systems, home automation, trust managementand web services.This thesis presents a case study on the web application domain with Arctis,where the underlying technologies are AJAX (asynchronous JavaScriptand XML), GWT (Google Web Toolkit) framework and Java Servlet. Inorder to do that, this thesis contributes building up some reusable buildingblocks with Arctis tool suit. This thesis also describes a use case scenario touse those building blocks. This thesis work tries to implement the specifiedsystem and evaluates the resulting work.
93

Malware Detection Through Call Graphs

Kinable, Joris January 2010 (has links)
Each day, anti-virus companies receive large quantities of potentially harmful executables. Many of the malicious samples among these executables are variations of earlier encountered malware, created by their authors to evade pattern-based detection. Consequently, robust detection approaches are required, capable of recognizing similar samples automatically.In this thesis, malware detection through call graphs is studied. In a call graph, the functions of a binary executable are represented as vertices, and the calls between those functions as edges. By representing malware samples as call graphs, it is possible to derive and detect structural similarities between multiple samples. The latter can be used to implement generic malware detection schemes, which can proactively detect existing versions of the malware, as well as future releases with similar characteristics.To compare call graphs mutually, we compute pairwise graph similarity scores via graphmatchings which minimize an objective function known as the Graph Edit Distance. Finding exact graph matchings is intractable for large call graph instances. Hence we investigate several efficient approximation algorithms. Next, to facilitate the discovery of similar malware samples, we employ several clustering algorithms, including variations on k-medoids clustering and DBSCAN clustering algorithms. Clustering experiments are conducted on a collection of real malware samples, and the results are evaluated against manual classifications provided by virus analysts from F-Secure Corporation. Experiments show that it is indeed possible to accurately detect malware families using the DBSCAN clustering algorithm. Based on our results, we anticipate that in the future it is possible to use call graphs to analyse the emergence of new malware families, and ultimately to automate implementinggeneric protection schemes for malware families.
94

Security Analysis of Future Internet Architectures

Ballester Lafuente, Carlos January 2010 (has links)
During the last decades, Internet has evolved from host-centric toinformation-centric in the sense that it is information and data what matters,regardless of where it is located. Meanwhile, Internet's architecturestill remains the same as it was in its origins and still focuses on host-tohostcommunication, putting too much emphasis on the "where" ratherthan putting it on the "what".Original Internet's architecture also introduces several security aws suchas DoS and DDoS, spoong and spam, and other non-security relatedproblems such as availability or location dependence related issues. Inorder to address these issues, several new architectures and protocols havebeen proposed. Some of them aim at redesigning totally the architecture ofInternet from scratch, while others aim at improving it without redesigningit totally.The aim of this Master Thesis is to analyze these new protocols and architecturesfrom a security point of view in order to determine whether thesecurity claims made are true or not. The security analysis is made basedon RFCs, technical papers and project deliverables. The results obtainedhave uncovered some security issues in several of the new protocols andarchitectures and have provided some insight into further improving them.
95

Energy Efficiency of Streaming over Mobile Ad-hoc Networks

Pattabiraman, Prashanth January 2010 (has links)
Hand held mobile devices are widely used today primarily due to their rich functionality and the ease of portability. However, the battery life of these devices is very limited and deploying resource hungry applications such as streaming on these mobile devices is a challenging task. It is extremely important to maximize the efficient use of the contained resources on these devices especially when they participate in a mobile ad hoc network. The optimization can occur in any layer of the OSI stack, however, this thesis work focuses only on the routing protocols used in the network layer. In this thesis work we have been able to evaluate the Energy Efficiency of the four most widely used MANET routing protocols (AODV, OLSR, DSDV and DSR) in terms of their energy consumption and performance. The initial phase of the work was carried out using the Network Simulator 2(NS2) tool and later the observations were done on a real world MANET testbed. The influence of several external factors on the performance and energy consumption are also taken into consideration while performing the simulations and experiments. The results obtained from our observations provide both qualitative and quantitative analysis of the routing protocols. Furthermore, it also highlights how the behaviour of the protocols are sometimes highly unpredictable, yielding results that we may not expect.
96

Secure data aggregation for wireless sensor network

Tran-Thi-Thuy, Trang January 2010 (has links)
Like conventional networks, security is also a big concern in wireless sensor networks. However, security in this type of networks faces not only typical but also new challenges. Constrained devices, changing topology or susceptibility to unprecedented security threats such as node capture and node compromise has refrained developers from applying conventional security solutions into wireless sensor networks. Hence, developing security solutions for wireless sensor networks not only requires well security analysis but also offers a low power and processing consuming.In this thesis, we implemented security solution targeting IRIS sensor motes. In our implementation, a public key-based key exchange is used to establish shared secret keys between sensor nodes. These secret keys are used to provide authenticity, integrity and freshness for transmission data. Our implementation ensures the flexibility in integrating our solution with available TinyOS operating system. Additionally, the thesis work also focuses on evaluating the performance in wireless sensor networks both in memory and energy consuming.
97

Employing Ethernet Multiple Spanning Tree Protocol in an OpMiGua network

Veisllari, Raimena January 2010 (has links)
Hybrid optical packet/circuit switched networking architectures are increasingly becoming an interesting research field. They integrate and combine the high resource utilization of statistically multiplexed packet switched networks with the low processing requirements and guaranteed quality of service provided by circuit switched networks. The aim of this thesis is to integrate the OpMiGua hybrid optical network with Ethernet. Specifically, the work is focused on the compatibility of the Ethernet’s loop-free topology protocols with the redundant multiple traffic service paths of OpMiGua. We analyse the problems and limitations imposed on the network architecture and propose our topology solution called the SM chain-connectivity. The analysis and the proposed schemes are verified based on results obtained from simulations. Furthermore, we design an integrated logical OpMiGua node that relies on an Ethernet switch instead of the Optical Packet Switch for the Statistically Multiplexed traffic. To date, to our knowledge there are no studies analysing the compatibility of Ethernet and its protection mechanisms in a hybrid optical network. This is the first work addressing the use of Ethernet in OpMiGua.
98

Automated Security Analysis of Infrastructure Clouds

Bleikertz, Sören January 2010 (has links)
Cloud computing has gained remarkable popularity in the recent years by a wide spectrum of consumers, ranging from small start-ups to governments. However, its benefits in terms of flexibility, scalability, and low upfront investments, are shadowed by security challenges which inhibit its adoption. In particular, these highly flexible but complex cloud computing environments are prone to misconfigurations leading to security incidents, eg, erroneous exposure of services due to faulty network security configurations. In this thesis we present a novel approach in the security assessment of multi-tier architectures deployed on infrastructure clouds such as Amazon EC2. In order to perform this assessment for the currently deployed configuration, we automated the process of extracting the configuration using the Amazon API and translating it into a generic data model for later analysis. In the assessment we focused on the reachability and vulnerability of services in the virtual infrastructure, and presented a way for the visualization andautomated analysis based on reachability and attack graphs. We proposed a query and policy language for the analysis which can be used to obtain insights into the configuration and to specify desired and undesired configurations. We have implemented the security assessment in a prototype and evaluated it for practical andtheoretical scenarios. Furthermore, a framework is presented which allows the evaluation of configuration changes in the agile and dynamic cloud environments with regard to properties like vulnerabilities or expected availability. In case of a vulnerability perspective, this evaluation can be used to monitor the securitylevels of the configuration over its lifetime and to indicate degradations.
99

Specification of security properties by JML

Dulaj, Ilir January 2010 (has links)
Nowadays, verification of programs is gaining increased importance. The software industry appears more and more interested in methods and tools to ensure security in their applications. Java Modeling Language has been successfully used in the past by programmers to express their intentions in the Design by Contract fashion in sequential programming. One of the design goals of JML was to improve the functional software correctness of Java applications. Regarding the verification of security properties, JML was mostly successful in Java Smart Card applets due to the specifics of these applications. In this thesis work we investigate the feasibility of JML to express high-level security properties in Java applications that have more realistic requirements and are implemented in the object oriented technology. We do a threat analysis of a case study regarding a medical clinic and derive the required security properties to secure the application. We develop a prototype application where we specify high-level security properties with JML and use a runtime assertion checking tool to verify the code. We model the functional behavior of the prototype that establishes the security proper-ties as a finite state automaton. Our prototype is developed based on this automaton. States and state transitions modeled in the automaton are expressed in the prototype with JML annotations and verified during runtime. We observe that currently available features in JML are not very feasible to capture the security related behavior of Java programs on the level of the entire application.
100

Share Computing Protocols over Fields and Rings

Kahrs, Katharina January 2009 (has links)
<p>In this thesis, we explain linear secret sharing schemes, in particular multiplicative threshold linear secret sharing schemes, over fields and rings in a compact and concise way. We explain two characterisations of linear secret sharing schemes, and in particular, we characterise threshold linear secret sharing schemes. We develop an algorithm to generate all multiplicative $(t+1)$-out-of-$n$ threshold linear secret sharing schemes over a field $mathbb{Z}sb{p}$. For the ring $mathbb{Z}sb{2sp{32}}$, we explain the generation of secret sharing schemes for threshold access structures and prove the non-existence of $(t+1)$-out-of-$n$ threshold linear secret sharing schemes with $n > t+1$.</p>

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