RF positioning methods have various tradeoffs that make them suitable for differing applications. This thesis identifies the most prominent positioning methods and deter-mines their suitability for context aware applications in pub-lic spaces using a number of different factors. This thesis first explores the physical characteristics of GPS, GSM, 802.11 and Bluetooth focusing on coverage and accuracy in both a historical and forward looking context. Next, it explores what it means for an application to be context aware and how that translates into building applications that are used in the context of public places. This thesis then reflects on the intersection of the two and explores some challenges related to practical implementations. In order to further explore these challenges, it assesses a high accuracy use case of merging Bluetooth positioning with augmented reality and virtual reality applications. We find that in the last decade Bluetooth has made rapid advancements in relation to competing technologies, but it is still far from ideal in all situations, especially when the situation requires extremely high accuracy.

Many competing designs for Distributed Hash Tables exist exploring multiple models of addressing, routing and network maintenance. Designing a general theoretical model and implementation of a Distributed Hash Table allows exploration of the possible properties of Distributed Hash Tables. We will propose a generalized model of DHT behavior, centered on utilizing Delaunay triangulation in a given metric space to maintain the networks topology. We will show that utilizing this model we can produce network topologies that approximate existing DHT methods and provide a starting point for further exploration. We will use our generalized model of DHT construction to design and implement more efficient Distributed Hash Table protocols, and discuss the qualities of potential successors to existing DHT technologies.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Sensor technology is continually advancing to meet demands of a wide range of potential applications. Many of these applications could be better served by distributed sensing than by traditional centralized sensing. To support these emerging applications, it is important to design and develop a unified framework for communication and network infrastructure capable of supporting various sensing functions. A research prototype operating in the 915 MHz Industrial, Scientific, and Medical band (ISM band) has been developed as potentially the core component of this infrastructure. In this paper, we will present the design and optimization of the system, data processing procedures, system parameters, network protocols, and experimental results.

The Internet was originally designed to be a next-generation phone system that could withstand a Soviet attack. Today, we ask the Internet to perform tasks that no longer resemble phone calls in the face of threats that no longer resemble Soviet bombardment. However, we have come to rely on names that can be subverted at every level of the stack or simply be allowed to rot by their original creators. It is possible for us to build networks of content that serve the content distribution needs of today while withstanding the hostile environment that all modern systems face. This dissertation presents the Cryptographically Curated File System (CCFS), which offers five properties that we feel a modern content distribution system should provide. The first property is Strong Links, which maintains that only the owner of a link can change the content to which it points. The second property, Permissionless Distribution, allows anyone to become a curator without dependence on a naming or numbering authority. Third, Independent Validation arises from the fact that the object seeking affirmation need not choose the source of trust. Connectivity, the fourth property, allows any curator to delegate and curate the right to alter links. Each curator can delegate the control of a link and that designee can do the same, leaving a chain of trust from the original curator to the one who assigned the content. Lastly, with the property of Collective Confidence, trust does not need to come from a single source, but can instead be an aggregate affirmation. Since CCFS embodies all five of these properties, it can serve as the foundational technology for a more robust Web. CCFS can serve as the base of a web that performs the tasks of today’s Web, but also may outperform it. In the third chapter, we present a number of scenarios that demonstrate the capacity and potential of CCFS. The system can be used as a publication platform that has been re-optimized within the constraints of the modern Internet, but not the constraints of decades past. The curated links can still be organized into a hierarchical namespace (e.g., a Domain Naming System (DNS)) and de jure verifications (e.g., a Certificate Authority (CA) system), but also support social, professional, and reputational graphs. This data can be distributed, versioned, and archived more efficiently. Although communication systems were not designed for such a content-centric system, the combination of broadcasts and point-to-point communications are perfectly suited for scaling the distribution, while allowing communities to share the burdens of hosting and maintenance. CCFS even supports the privacy of friend-to-friend networks without sacrificing the ability to interoperate with the wider world. Finally, CCFS does all of this without damaging the ability to operate search engines or alert systems, providing a discovery mechanism, which is vital to a usable, useful web. To demonstrate the viability of this model, we built a research prototype. The results of these tests demonstrate that while the CCFS prototype is not ready to be used as a drop-in replacement for all file system use cases, the system is feasible. CCFS is fast enough to be usable and can be used to publish, version, archive, and search data. Even in this crude form, CCFS already demonstrates advantages over previous state-of-the-art systems. When the Internet was designed, there were relatively fewer computers that were far weaker than the computers we have now. They were largely connected to each other over reliable connections. When the Internet was first created, computing was expensive and propagation delay was negligible. Since then, the propagation delay has not improved on a Moore’s Law Curve. Now, latency has come to dominate all other costs of retrieving content; specifically, the propagation time has come to dominate the latency. In order to improve the latency, we are paying more for storage, processing, and bandwidth. The only way to improve propagation delay is to move the content closer to the destination. In order to have the content close to the demand, we store multiple copies and search multiple locations, thus trading off storage, bandwidth, and processing for lower propagation delay. The computing world should re-evaluate these trade-offs because the situation has changed. We need an Internet that is designed for the technologies used today, rather than the tools of the 20th century. CCFS, which regards the trade-off for lower propagation delay, will be better suited for 21st-century technologies. Although CCFS is not preferable in all situations, it can still offer tremendous value. Better robustness, performance, and democracy make CCFS a contribution to the field. Robustness comes from the cryptographic assurances provided by the five properties of CCFS. Performance comes from the locality of content. Democracy arises from the lack of a centralized authority that may grant the right of Free Speech only to those who espouse rhetoric compatible with their ideals. Combined, this model for a cryptographically secure, content-centric system provides a novel contribution to the state of communications technology and information security.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Bidirectional networked radio frequency (RF) communications between the ground and test articles are quickly becoming a normal mode of operation. Not only can devices be remotely controlled, but other networking technologies are emerging into flight test. Voice over IP (VoIP) is ubiquitous in the workplace and in homes, but it presents unique challenges when used to communicate between test articles. This paper presents some issues to be considered and test results to help aid deployment of VoIP systems in network-based test systems such as iNET's Telemetry Network System (TmNS).

Research on business networks has traditionally focussed on understanding the nature of relationships in networks but seldom the outcomes from business networking activities. This thesis examines the benefits from business networking from the perspective of firms in the West Midlands and explains the factors which improve networking performance. Networking is hailed by academics and marketing practitioners as a way to improve business performance. Firms are encouraged to invest resources in networking activities, without necessarily being able to measure the result. Researchers following in the ‘markets as networks’ tradition have identified understanding the benefits from business networking activities as a subject for further investigation. Using survey data from 298 firms in the West Midlands, the findings show that strength of relationship, planned networking behaviour and networking intensity to be significant indicators of networking performance. Analysis also shows degree of embeddedness to have a mediating effect on networking performance. This study provides empirical support for the idea that firms which adopt a systematic approach to business networking achieve better outcomes in terms of networking performance when measured as a percentage of sales turnover, compared to firms adopting an ad-hoc approach to networking. This study contributes to the marketing and markets as networks literature as well as advancing the conceptualisation of networking performance measured in terms of sales turnover. The thesis offers insights from the focal firm’s perspective as to why business networking is important and identifies factors which contribute to positive networking outcomes and a measure of networking performance

HMS Industrial networks is a company that offers communication solutions for automation systems. There exists an abundance of different industrial network technologies and HMS manufactures gateways that translate and allow communication between the different networks.The multiplicity of network technologies introduces problems when it comes to monitoring the processes in an automation system. It is desirable to be able to access the process data through a single network technology and this is what OPC UA is used for. Briefly, OPC UA can be described as an interface for exchange ofprocess data in automation systems. HMS has noticed a rising trend in the interest for OPC UA and therefore wants to investigate the possibility to use OPC UA on their platform, the Anybus X-Gateway. The goal of this thesis has been to port an OPC UA stack, provided by the OPCfoundation, to the HMS operating system running on an Anybus X-Gateway. The port has been successful and has been verified by unit tests and a test application. Thus, a first step towards a complete OPC UA product has been taken. Further, the thesis presents a theoretical summary about real-time operating systems to explain their function and usage.

People make a range of everyday decisions about how and whether to share content with different people, across different platforms and services, during a variety of tasks. These sharing decisions can encompass complex preferences and a variety of access-control dimensions. In this thesis I examine potential methods for improving sharing mechanisms by better understanding the everyday online sharing environment and evaluating a potential sharing tool. I first present two studies that explore how current sharing mechanisms may fall short on social networking sites, leading to suboptimal outcomes such as regret or self censorship. I discuss the implications of these suboptimal outcomes for the design of behavioral nudging tools and the potential for improving the design of selective-sharing mechanisms. I then draw on a third study to explore the broader “ecosystem” of available channels created by the services and platforms people move between and combine to share content in everyday contexts. I examine the role of selective-sharing features in the broader audience-driven and task-driven dynamics that drive sharing decisions in this environment. I discuss the implications of channel choice and dynamics for the design of selective-sharing mechanisms. Using insights from current shortfalls and ecosystem-level dynamics I then present a fourth study examining the potential for adding topic-driven sharing mechanisms to Facebook. I use design mockups and a lab-based interview to explore participants’ hypothetical use cases for such mechanisms. I find that these mechanisms could potentially be useful in a variety of situations, but successful implementation would require accounting for privacy requirements and users’ sharing strategies.

Agritourism is increasingly prevalent in Canadian society and affords individuals the opportunity to experience and learn about agriculture. Social networking sites can allow agritourism providers and consumers to engage outside of the agritourism context. This research used qualitative and quantitative content analysis and semi-structured interviews to understand how agritourism providers and consumers interact on Facebook, Twitter, and Instagram; why agritourism providers are using social networking sites in general; and if social networking sites can be used to facilitate free-choice learning. Customer Relationship Management and the Contextual Model of Learning were used as frameworks to better understand these interactions. The results and findings are discussed and confirm that agritourism providers believe educational opportunities can be fostered on social networking sites, but are primarily using Facebook, Twitter, and Instagram to promote connections between consumers and agritourism organizations. / October 2016

ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada