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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.
1

Securing Distributed Context Exchange Networks in Mobile Environments

Kafle, Sijan January 2013 (has links)
The use of the internet has exploded with many more context aware applications for different services, simplifying the use and access for human requirements. The present situation shows an increasing number of devices from computers to sensors and actuators that are connected to the internet. MediaSense[1] is a growing framework that provides a platform for applications to connect these devices (smart-phones, sensors, actuators etc.) and provide services using the internet. Applications based on the MediaSense[1] framework access globally available sensors to provide contextual information with regards to a situation and provide better services. However, information flowing between the devices or sensors are open to the internet without any security. Thus, the focus of this thesis is on the development of a security mechanism for the MediaSense framework which is a fully distributed network. The task involves analyzing the security measures with and without centralized authority as well as the advantages and disadvantages of both scenarios regarding the MediaSense framework and proposing appropriate solutions to achieve the maximum possible security on the framework. The first challenge of this thesis is to identify different properties required for a security mechanism which is capable of secure key distribution and secure peer to peer communication among MediaSense instances without having any centralized authority. Therefore, this thesis proposes a resilient solution, namely, a security architecture for MediaSense which is capable of performing in a distributed environment with the ability of key distribution and management and thus securing the communication using different encryption techniques. The next challenge to the security architecture is to store the keys securely and prevent any unauthorized access from a third party. The thesis proposes the use of built in Java Application Programming Interface(API), “KeyStore” to store valuable keys locally. Thus, by addressing these challenges and other related issues, this thesis forms a security architecture or mechanism that is adaptive to a distributed system and utilizes encryption algorithms, key distribution and secure storage of the keys. To support these proposals, this thesis has developed a proof of concept application and prototypes to verify the approach. In addition, the thesis has implemented security features from the security architecture as an extension to the MediaSense framework. Hence, in conclusion, this thesis proposal regarding a security architecture for MediaSense has the ability to provide the necessary security together with the required key distribution mechanism to the framework without any centralized authority.
2

NAT traversal techniques for MediaSense open source platform

Aryefyev, Maksym January 2013 (has links)
This thesis project concerns NAT traversal techniques and their application to P2P networking with regard to MediaSense platform. Since MediaSense open source platform, developed by Mid Sweden University, utilizes the benefits of P2P networking, it also suffers from the drawbacks provided by NAT. The issue of NAT traversal is not trivial due to the fact that the behavior of NAT devices is not standardized and vendors are free to provide their own implementations. The common knowledge is, that at least four main types of NATs exist, differing in the filtering and mapping algorithms employed. NAT traversal techniques vary accordingly. No single technique can handle all the cases. Most of the techniques can handle up to three main types of NAT. The last type is usually used in large corporate networks and is called the Symmetric NAT. The most viable, and basically the only available technique for its traversal, is data relaying. This thesis builds a NAT traversal module for the MediaSense platform. The main purpose of this module is to provide seamless NAT traversal capabilities to the platform. The module does this in several steps: UPnP enabled device discovery, NAT type determination and data relaying via the proxy. Firstly the module attempts to discover the presence of a UPnP enabled Internet Gateway Device on the network. If such a device is present on the network, a port mapping can be created, making the node located behind NAT accessible from the public Internet. If a UPnP enabled device was not found, the module will try to determine the type of NAT used. Based on the type of NAT used, the module can transit to either the proxy mode or request assistance of the STUN server to keep the created mapping alive. The resulting chapters provide the reader with the output produced by each step, conclusions the author has made while working on this project and some general ideas on future work within the subject.
3

Scalable Device Mobility – Mobile DCXP

Hussain, Ishfaq January 2014 (has links)
The continuously increasing Internet coverage and its availability has give rise to an issue that was once considered not important to take into consideration. Today a number of applications use the Internet to de-liver time critical messages. The usage of wireless Access Points involves a considerable percentage to connect mobile devices to the Internet pro-vider. However, these relatively cheaper Internet Access Points have their own disadvantages as compared to the GSM and ADSL. The access points cover a very limited area and thus in order to cover a wider area multiple access points must needs to be installed. In other words, as the user moves he/she is supposed to switch between access points. Never-theless, the basic problem in such cases is involves packet loss during handover. In today’s technological advancements these issues, though very small, are no more insignificant but are required to be handled prop-erly. So protocols such as MobileIP, LISP, HOST have been proposed and are currently being used for such a purpose. Furthermore, in this thesis a mechanism to reduce such packet losses has been studied and proposed in relation to the SensibleThings Internet-of-things platform. A workaround solution known as Mobile DCXP has been proposed and implemented and comparisons with the existing system have been carried out. In addition, a generic solution has been discussed in detail and compared with the Mobile DCXP. However, the implementation of the generic solution has been deferred to the future. The concept of Mobile DCXP has been illustrated with proof-of-concept apps and an implementation of a simple Android Application known as IChat has been conduct. The IChat is a simple chat app that is used in the experi-ment to determine out the packet lost during handover and to carry out a comparison. Finally, based on the data collected from IChat, an evaluation of Mobile DCXP has been presented and a performance comparison with Mobile Proxy DCXP has been illustrated with charts. Furthermore, in the conclusion Mobile DCXP could minimize packet loss as compared to the existing system.
4

Attacks on structured P2P overlay networks : Simulating Sybil Attacks

Tefera, Mismaku Hiruy January 2014 (has links)
No description available.
5

Reliable UDP and Circular DHT implementation for the MediaSense Open-Source Platform

Schröder, Timo, Rüter, Florian January 2012 (has links)
MediaSense is an EU funded platform that is an implementation of an Internet-of-Things framework. This project adds two fundamental functions to it, namely, a new lookup service based on a peer-to-peer Distributed Hash Table (DHT) called Chord and a reliable communication protocol based on UDP (RUDP). The lookup service makes the use of a central server, that can be a single point of failure or get compromised, unnessecary. Reliable UDP transmits data from the very first packet onwards and avoids any connection management as itis packet based. The methodology for both functions was to develop a simulation environment, compatible to MediaSense, at its initiation, at which point its functionality can be tested and measurements can betaken. The resulting DHT simulation environment enables there to be deep insight into and a control of the state and action of the DHT. The resulting graphs show the performance properties of both the DHT and RUDP. In conclusion, the MediaSense platform has been extended by means of two usable functionalities and which also leaves space for further development such as for security enhancements and performance increases. / MediaSense
6

Surveillance Applications : Image Recognition on the Internet of Things

Rönnqvist, Patrik January 2013 (has links)
This is a B.Sc. thesis within the Computer Science programme at the Mid Sweden University. The purpose of this project has been to investigate the possibility of using image based surveillance in smart applications on the Internet-of-Things. The goals involved investigating relevant technologies and designing, implementing and evaluating an application that can perform image recognition. A number of image recognition techniques have been investigated and the use of color histograms has been chosen for its simplicity and low resource requirement. The main source of study material has been the Internet. The solution has been developed in the Java programming language, for use on the Android operating system and using the MediaSense platform for communication. It consists of a camera application that produces image data and a monitor application that performs image recognition and handles user interaction. To evaluate the solution a number of tests have been performed and its pros and cons have been identified. The results show that the solution can differentiate between simple colored stick figures in a controlled environment. Variables such as lighting and the background are significant. The application can reliably send images from the camera to the monitor at a rate of one image every four seconds. The possibility of using streaming video instead of images has been investigated but found to be difficult under the given circumstances. It has been concluded that while the solution cannot differentiate between actual people it has shown that image based surveillance is possible on the IoT and the goals of this project have been satisfied. The results were expected and hold little newsworthiness. Suggested future work involves improvements to the MediaSense platform and infrastructure for processing and storing data. / MediaSense
7

Distributed Immersive Participation : Realising Multi-Criteria Context-Centric Relationships on an Internet of Things

Walters, Jamie January 2014 (has links)
Advances in Internet-of-Things integrate sensors and actuators in everyday items or even people transforming our society at an accelerated pace. This occurs in areas such as agriculture, logistics, transport, healthcare, and smart cities and has created new ways to interact with and experience entertainment, (serious) games, education, etc. Common to these domains is the challenge to realize and maintain complex relations with any object or individual globally, with the requirement for immediacy in maintaining relations of varying complexity. Existing architectures for maintaining relations on the Internet, e.g., DNS and search engines are insufficient in meeting these challenges. Their deficiencies mandate the research presented in this dissertation enabling the maintenance of dynamic and multi-criteria relationships among entities in real-time in an Internet-of-Things while minimizing the overall cost for maintaining such context-centric relationships. A second challenge is the need to represent nearness in context-centric relationships, since solutions need to build on what is closely related. The dissertation shows that the proximity on relations can be used to bring about the scalability of maintaining relationships across the IoT. It successfully demonstrates the concept and feasibility of self-organizing context-centric overlay networks for maintaining scalable and real-time relationships between endpoints co-located with associated physical entities. This is complemented by an object model for annotating objects and their relationships as derived and defined over the underpinning context interactions. Complementing measures of nearness are added through a non-metric multi-criteria approach to evaluating the notion of context proximity. A query language and an extension to the publish-subscribe approaches achieves distributed support for discovering such relationships; locating entities relative to a defined hyper-sphere of interest. Furthermore, it introduces adaptive algorithms for maintaining such relationships at minimal overall costs. The results demonstrate the feasibility of moving towards context-centric approaches to immersion and that such approaches are realizable over vast and distributed heterogeneous collections of user and their associated context information.

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