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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.
141

Reputation and trust-based security in wireless sensor networks

Unknown Date (has links)
This dissertation presents the results of research that led to the development of a novel reputation and trust-based monitoring paradigm for secure and reliable computing in Wireless Sensor Networks (WSNs). WSNs have undergone tremendous technological advances over the last few years. They have caused a giant leap toward "proactive computing," a paradigm where computers anticipate human needs and, when necessary, act on their behalf. Therefore, we cannot deploy such a critical technology without first addressing the security and privacy challenges to ensure that it does not turn against those whom it is meant to benefit. The core application of WSNs is to detect and report events, be it military or civilian applications. The building blocks of a WSN are small, battery-powered, lowcost, self-contained devices called "sensors" that measure factors like light, temperature, pressure, vibration, motion, etc. A WSN usually consists of hundreds of thousands of sensors that operate in unattended, hostile territories to monitor a given geographical area. Once deployed, the wireless sensors self-organize into ad-hoc wireless networks in order to cope with the dynamics of the surveillance field. During the post deployment phase, the wireless sensors aggregate data, then process and generate a report, which is subsequently relayed from one sensor to the next using secure multi-hop routing until the data reaches its desired destination, which is usually the sink. Since sensors operate in unattended and hostile territories, the adversary can capture a sensor node physically and extract all the information stored onboard, including cryptographic keying material. With this unique situation, WSNs are subject to a unique attack referred to as an "Insider Attack," in which the adversary becomes a legitimate member of the network being represented by the captured node. / To overcome this unique situation, a distributed Reputation and Trust-based Monitoring System (RTMS) is required. The most critical contribution of this dissertation work has been the proposal and design of a novel, clique-based, distributed group-key establishment protocol with specific application to RTMSs. We have also proposed and evaluated the application of RTMS models for securing beacon-based localization in WSNs addressing information asymmetry attacks, and proposed a novel k-parent tree model for securing broadcast communication in WSNs with an underlying RTMS model. Other issues addressed in this dissertation work include the proposal of a Connected Dominating Set (CDS) based reputation dissemination and bootstrapping model. This model also enables secure, certificateless node mobility and enables the model to be robust to ID Spoofing and node replication attacks. / by Avinash Srinivasan. / Thesis (Ph.D.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, FL : 2008 Mode of access: World Wide Web.
142

Web-based wireless sensor network monitoring using smartphones

Unknown Date (has links)
This thesis consists of the development of a web based wireless sensor network (WSN) monitoring system using smartphones. Typical WSNs consist of networks of wireless sensor nodes dispersed over predetermined areas to acquire, process, and transmit data from these locations. Often it is the case that the WSNs are located in areas too hazardous or inaccessible to humans. We focused on the need for access to this sensed data remotely and present our reference architecture to solve this problem. We developed this architecture for web-based wireless sensor network monitoring and have implemented a prototype that uses Crossbow Mica sensors and Android smartphones for bridging the wireless sensor network with the web services for data storage and retrieval. Our application has the ability to retrieve sensed data directly from a wireless senor network composed of Mica sensors and from a smartphones onboard sensors. The data is displayed on the phone's screen, and then, via Internet connection, they are forwarded to a remote database for manipulation and storage. The attributes sensed and stored by our application are temperature, light, acceleration, GPS position, and geographical direction. Authorized personnel are able to retrieve and observe this data both textually and graphically from any browser with Internet connectivity or through a native Android application. Web-based wireless sensor network architectures using smartphones provides a scalable and expandable solution with applicability in many areas, such as healthcare, environmental monitoring, infrastructure health monitoring, border security, and others. / by Anthony M. Marcus. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
143

Secure routing in wireless sensor networks

Unknown Date (has links)
This research addresses communication security in the highly constrained wireless sensor environment. The goal of the research is twofold: (1) to develop a key management scheme that provides these constrained systems with the basic security requirements and evaluate its effectiveness in terms of scalability, efficiency, resiliency, connectivity, and flexibility, and (2) to implement this scheme on an appropriate routing platform and measure its efficiency. / The proposed key management scheme is called Hierarchical Key Establishment Scheme (HIKES). In HIKES, the base station, acting as the central trust authority, empowers randomly selected sensors to act as local trust authorities, authenticating on its behalf the cluster members and issuing to them all secret keys necessary to secure their communications. HIKES uses a novel key escrow scheme that enables any sensor node selected as a cluster head to generate all the cryptographic keys needed to authenticate other sensors within its cluster. This scheme localizes secret key issuance and reduces the communication cost with the base station. The key escrow scheme also provides the HIKES with as large an addressing mechanism as needed. HIKES also provides a one-step broadcast authentication mechanism. HIKES provides entity authentication to every sensor in the network and is robust against most known attacks. We propose a hierarchical routing mechanism called Secure Hierarchical Energy-Efficient Routing protocol (SHEER). SHEER implements HIKES, which provides the communication security from the inception of the network. SHEER uses a probabilistic broadcast mechanism and a three-level hierarchical clustering architecture to improve the network energy performance and increase its lifetime. / Simulation results have shown that HIKES provides an energy-efficient and scalable solution to the key management problem. Cost analysis shows that HIKES is computationally efficient and has low storage requirement. Furthermore, high degree of address flexibility can be achieved in HIKES. Therefore, this scheme meets the desired criteria set forth in this work. Simulation studies also show that SHEER is more energy-efficient and has better scalability than the secure version of LEACH using HIKES. / by Jamil Ibriq. / Thesis (Ph. D.)--Florida Atlantic University, 2007. / Includes bibliography. / Also available in print. / Electronic reproduction. Boca Raton, FL : 2007. Mode of access: World Wide Web.
144

Defining the Information Security Posture: An Empirical Examination of Structure, Integration, and Managerial Effectiveness

Young, Randall Frederick 08 1900 (has links)
The discipline of information security management is still in its infancy as evidenced by the lack of empirical scholarly work in this area. Most research within the information security domain focuses on specific technologies and algorithms and how it impacts the principles of confidentiality, integrity, and availability. But, an important area receiving little attention is the antecedents of effective information security management at the organizational level (Stanton, Guzman, Stam & Caldera, 2003). The little empirical research that has been conducted in this area has shown that information security management in many organizations is poor (Baskerville, 1993; Shimeall & McDermott, 1999). Several researchers have identified the need for methods to measure the organization-wide information security posture of organizations (Eloff & Von Solms, 2000; James, 1996). This dissertation attempts to measure the organization-wide information security posture by examining benchmark variables that assess role, planning orientation, and performance structure within the organization. Through this conceptualization of an organization's information security posture, a means is presented to measure overall information security and how it impacts the effective utilization of information security strategies. The presence of the dependent variable, effectiveness, gives academics and practitioners a success measure which can guide more effective decision making in the information security domain. An additional aim of this dissertation is to empirically examine the influence of management practices and decisions on effective use of information security strategies within the organization. The issues of centralization versus decentralization of information security activities will be evaluated along with its impact on information security posture of organizations and the effectiveness of the organization's information security strategies. Data was collected from 119 IT and information security executives. Results show that how the organization structures information security activities is not correlated with more effective utilization of information security strategies. Meanwhile, the organization's information security posture is significantly correlated with more effective utilization of information security strategies. The implications of this research is discussed.
145

Economic issues in distributed computing

Huang, Yun, 1973- 28 August 2008 (has links)
On the Internet, one of the essential characteristics of electronic commerce is the integration of large-scale computer networks and business practices. Commercial servers are connected through open and complex communication technologies, and online consumers access the services with virtually unpredictable behavior. Both of them as well as the e-Commerce infrastructure are vulnerable to cyber attacks. Among the various network security problems, the Distributed Denial-of-Service (DDoS) attack is a unique example to illustrate the risk of commercial network applications. Using a massive junk traffic, literally anyone on the Internet can launch a DDoS attack to flood and shutdown an eCommerce website. Cooperative technological solutions for Distributed Denial-of-Service (DDoS) attacks are already available, yet organizations in the best position to implement them lack incentive to do so, and the victims of DDoS attacks cannot find effective methods to motivate the organizations. Chapter 1 discusses two components of the technological solutions to DDoS attacks: cooperative filtering and cooperative traffic smoothing by caching, and then analyzes the broken incentive chain in each of these technological solutions. As a remedy, I propose usage-based pricing and Capacity Provision Networks, which enable victims to disseminate enough incentive along attack paths to stimulate cooperation against DDoS attacks. Chapter 2 addresses possible Distributed Denial-of-Service (DDoS) attacks toward the wireless Internet including the Wireless Extended Internet, the Wireless Portal Network, and the Wireless Ad Hoc network. I propose a conceptual model for defending against DDoS attacks on the wireless Internet, which incorporates both cooperative technological solutions and economic incentive mechanisms built on usage-based fees. Cost-effectiveness is also addressed through an illustrative implementation scheme using Policy Based Networking (PBN). By investigating both technological and economic difficulties in defense of DDoS attacks which have plagued the wired Internet, our aim here is to foster further development of wireless Internet infrastructure as a more secure and efficient platform for mobile commerce. To avoid centralized resources and performance bottlenecks, online peer-to-peer communities and online social network have become increasingly popular. In particular, the recent boost of online peer-to-peer communities has led to exponential growth in sharing of user-contributed content which has brought profound changes to business and economic practices. Understanding the dynamics and sustainability of such peer-to-peer communities has important implications for business managers. In Chapter 3, I explore the structure of online sharing communities from a dynamic process perspective. I build an evolutionary game model to capture the dynamics of online peer-to-peer communities. Using online music sharing data collected from one of the IRC Channels for over five years, I empirically investigate the model which underlies the dynamics of the music sharing community. Our empirical results show strong support for the evolutionary process of the community. I find that the two major parties in the community, namely sharers and downloaders, are influencing each other in their dynamics of evolvement in the community. These dynamics reveal the mechanism through which peer-to-peer communities sustain and thrive in a constant changing environment. / text
146

An investigation of high school learners using MXIT, and their attitudes towards mobile security.

Bhoola, Nisha. 10 October 2013 (has links)
This research encompassed an investigation of high school learners using MXiT, and their attitudes towards mobile security guidelines. The research was conducted across thirteen schools in the Pinetown, ILembe and Umlazi districts of KwaZulu-Natal. The literature review has shown that the majority of security guidelines and their successful use depend on education and awareness of what these security measures are. Secure use of mobile social networking sites such as MXiT are best regulated by parental awareness and monitoring of children‟s online habits. This needs parents to be abreast of technology, its uses and benefits, the associated dangers, as well as how to encourage and monitor usage. The research was conducted by administering questionnaires to grades 8 to 11 inclusive in the three districts of KwaZulu-Natal. Out of the 1300 questionnaires handed out to learners, a total of 856 completed questionnaires (66%) were received and analysed. It was found from the study that 89,5% of under age users that participated in this research are using MXiT. Users are also not fully aware of the security features when using MXiT. It has also been found that African respondents as compared with non- African respondents are less aware of the possible dangers in using MXiT, less aware that criminals can use fake IDs and pretend to be someone they are not, and less aware that people can get addicted to MXiT. Learners are aware of the dangers that can be associated with MXiT; however they are prepared to talk to strangers and meet new people online, thus exposing themselves to these dangers. In conclusion, there is scope to improve the security measures for MXiT users, and there is a need to improve the levels of education around using these security features. / Thesis (M.Com.)-University of KwaZulu-Natal, Westville, 2011.
147

A framework for secure human computer interaction.

Johnston, James 02 June 2008 (has links)
This research is concerned with the development of a framework for the analysis and design of interfaces found in a security environment. An example of such an interface is a firewall. The purpose of this research is to use the framework as a method to improve the usability of an interface, thus aiding the user to implement the correct security features. The purpose is also to use the framework to assist in the development of trust between a user and a computer system. In this research the framework comprises six criteria which are used to analyse interfaces found in the traditional software environment, Internet banking environment and e-commerce environment. In order to develop the framework an overview of the fields of information security and human computer interfaces (HCI) is given. The overview provides background information and also establishes the existing research which has been done in these fields. Due to its popularity, the Windows Internet Connection Firewall is analysed in this research. Based on the criteria a level of trust fostered between the user and interface is calculated for the firewall. It is then shown how this level of trust can be improved by modifying the interface. A proposed interface for the firewall is presented according to the criteria. Interfaces found in the online Internet environment are discussed. This is important in order to identify the similarities and differences between traditional software interfaces and web interfaces. Due to these differences the criteria are modified to be relevant in the analysis and design of security interfaces found on the Internet. Three South African online banking websites are analysed according to the modified framework. Each interface is broken down into a number of components which are then analysed individually. The results of the analysis are compared between the three banking sites to identify the elements which make up a successful interface in an online banking environment. Lastly, three interfaces of e-commerce websites are analysed. Recommendations are made on how the interfaces can be improved, thus leading to a higher level of trust. / Labuschagne, L., Prof.
148

Effective monitoring of slow suspicious activites on computer networks

Kalutarage, H. K. January 2013 (has links)
Slow and suspicious activities on modern computer networks are increasingly hard to detect. An attacker may take days, weeks or months to complete an attack life cycle. A particular challenge is to monitor for stealthy attempts deliberately designed to stay beneath detection thresholds. This doctoral research presents a theoretical framework for effective monitoring of such activities. The main contribution of this work is a scalable monitoring scheme proposed in a Bayesian framework, which allows for detection of multiple attackers by setting a threshold using the Grubbs’ test. Second contribution is a tracing algorithm for such attacks. Network paths from a victim to its immediate visible hops are mapped and profiled in a Bayesian framework and the highest scored path is prioritised for monitoring. Third contribution explores an approach to minimise data collection by employing traffic sampling. The traffic is sampled using the stratification sampling technique with optimum allocation method. Using a 10% sampling rate was sufficient to detect simulated attackers, and some network parameters affected on sampling error. Final contribution is a target-centric monitoring scheme to detect nodes under attack. Target-centric approach is quicker to detect stealthy attacks and has potential to detect collusion as it completely independent from source information. Experiments are carried out in a simulated environment using the network simulator NS3. Anomalous traffic is generated along with normal traffic within and between networks using a Poisson arrival model. Our work addresses a key problem of network security monitoring: a scalable monitoring scheme for slow and suspicious activities. State size, in terms of a node score, is a small number of nodes in the network and hence storage is feasible for very large networks.
149

Design and evaluation of key redistribution mechanisms in wireless sensor networks

Law, Chun-fai, Terry., 羅俊輝. January 2007 (has links)
published_or_final_version / abstract / Electrical and Electronic Engineering / Master / Master of Philosophy
150

Key management for mobile ad-hoc networks

Budakoglu, Caner. 10 April 2008 (has links)
No description available.

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