Analysis and assessment software for multi-user collaborative cognitive radio networks

Computer simulations are without a doubt a useful methodology that allows to explore research queries and develop prototypes at lower costs and timeframes than those required in hardware processes. The simulation tools used in cognitive radio networks (CRN) are undergoing an active process. Currently, there is no stable simulator that enables to characterize every element of the cognitive cycle and the available tools are a framework for discrete-event software. This work presents the spectral mobility simulator in CRN called “App MultiColl-DCRN”, developed with MATLAB’s app designer. In contrast with other frameworks, the simulator uses real spectral occupancy data and simultaneously analyzes features regarding spectral mobility, decision-making, multi-user access, collaborative scenarios and decentralized architectures. Performance metrics include bandwidth, throughput level, number of failed handoffs, number of total handoffs, number of handoffs with interference, number of anticipated handoffs and number of perfect handoffs. The assessment of the simulator involves three scenarios: the first and second scenarios present a collaborative structure using the multi-criteria optimization and compromise solution (VIKOR) decision-making model and the naïve Bayes prediction technique respectively. The third scenario presents a multi-user structure and uses simple additive weighting (SAW) as a decision-making technique. The present development represents a contribution in the cognitive radio network field since there is currently no software with the same features

Campus Communications Systems: Converging Technologies

This book is a rewrite of Campus Telecommunications Systems: Managing Change, a book that was written by ACUTA in 1995. In the past decade, our industry has experienced a thousand-fold increase in data rates as we migrated from 10 megabit links (10 million bits per second) to 10 gigabit links (10 billion bits per second), we have seen the National Telecommunications Policy completely revamped; we have seen the combination of voice, data, and video onto one network; and we have seen many of our service providers merge into larger corporations able to offer more diverse services. When this book was last written, A CUT A meant telecommunications, convergence was a mathematical term, triple play was a baseball term, and terms such as iPod, DoS, and QoS did not exist. This book is designed to be a communications primer to be used by new entrants into the field of communications in higher education and by veteran communications professionals who want additional information in areas other than their field of expertise. There are reference books and text books available on every topic discussed in this book if a more in-depth explanation is desired. Individual chapters were authored by communications professionals from various member campuses. This allowed the authors to share their years of experience (more years than many of us would care to admit to) with the community at large. Foreword Walt Magnussen, Ph.D. Preface Ron Kovac, Ph.D. 1 The Technology Landscape: Historical Overview . Walt Magnussen, Ph.D. 2 Emerging Trends and Technologies . Joanne Kossuth 3 Network Security . Beth Chancellor 4 Security and Disaster Planning and Management Marjorie Windelberg, Ph.D. 5 Student Services in a University Setting . Walt Magnussen, Ph.D. 6 Administrative Services David E. O\u27Neill 7 The Business Side of Information Technology George Denbow 8 The Role of Consultants . David C. Metz Glossary Michelle Narcavag

Are secondary markets beneficial for a virtual world operator?

Selling virtual goods for real money has become the dominant business model for virtual worlds in the past decade. As the amount of money involved in virtual goods sales increases, market performance questions gain relevance. In this thesis, we examine the effects of secondary markets on the profitability of a virtual world service provider operating under a virtual goods sales model. More specifically, we ask whether the service provider should tolerate secondary markets or seek to kill them off. The structure of this thesis is as follows: we first review how virtual worlds operate as businesses and provide an analysis of the market conditions faced by a virtual world operator to provide sufficient context for the reader. We then examine the inner workings of virtual economies and review structures commonly encountered within them. Next, we conduct a literature review on real world secondary market models and analyses. Finally, we evaluate the implications of real world secondary market results on secondary markets for virtual goods. In the final section, we present conclusions and possible avenues for further study. We find that recent durable goods research suggests that a profit-maximizing monopolist will not shut down secondary markets, but will choose to reduce durability of goods instead and that these results can apply to virtual worlds as well. However, we also show that the question of allowing or not allowing secondary markets cannot be answered based on profitability alone and that service providers have to also account for externalities brought on by secondary markets

Journal of Air Transportation, Volume 3, No. 2

No abstract availabl

A Consumer Perspective on Mobile Market Evolution

In 2007 (Mazzoni, Castaldi, Addeo) we performed a wide research on consumer behavior in the Italian mobile communication market. Using a multidimensional segmentation approach, we identified three consumer clusters according to lifestyles, mobile phone use motivations and product attributes. One of the most interesting finding was that two clusters out of three were characterized by a minor propensity to an integrated and service-oriented use of mobile communication. In other words, some consumers conceived mobile phone not only as a simple communication devices, but more like a technologically advanced multipurpose tool. In mid-2000s Italian mobile companies and operators tried to push mobile communication market toward an integrated use, mostly relying on videophone communication. Although videophone communication had a very low impact on mobile market, integrated and service oriented use of cellular phones are becoming more and more the pillars of mobile communication market. Considering that the mobile communication market changes quickly under the spur of many technological innovations, new challenges or opportunities stem from the exploitation of innovations in mobile devices. The service economy (Fuchs, 1968; Gustafsson & Johnson, 2003), that implies the shift of manufacturers from goods selling to services delivering, is one of those challenges for mobile industry. Mainly since 2007, with the iPhone introduction, the “servitization” (Vandermerwe & Rada, 1988) has been an extending trend (Neely, 2007) among the mobile phones suppliers as they try to mix in their offerings either good and service, integrating phone devices with increasing software and applications. In a supplier perspective, this shift has an important impact on economical aspects, in term of cash-flows growth, or additional revenues - those streaming from selling more complementary services for products. Nevertheless, servitization also brings implications in the operation management, in the innovation strategy and compels providers to revise their business model also. But what is happening in the consumer perspective? A mass-market product like the mobile phone becomes extremely customizable by the complementary services that can be integrated into it: software updating allows customers to entail the mobile phone functionality on their unique needs. Analyzing the consumer perspective through the adoption of a behavior model above outlined (Mazzoni, 1995) and already applied and tested into the exploration of mobile market (Mazzoni, Castaldi, Addeo, 2007), this chapter aims - through a literature review - to understand how changes in the offerings can affect the three dimensions: lifestyles, use motivations and product attributes. Particularly, if shifts in product attributes are clear and evident, the chapter aims to consider the impact in the way in which customer’s expectations, needs and use of mobile phones are transforming

Satellite Cognitive Communications and Spectrum Regulation

Due to rapid increase of wireless users and the popularity of multimedia applications, the demand for wireless spectrum is increasing rapidly. However, due to current static spectrum policy, the available usable spectrum is becoming scarce while a significant amount of spectrum remains underutilized. In this aspect, cognitive communications can be considered as a promising technology to enhance spectrum usage efficiency by allowing the coexistence of heterogeneous networks within the same spectrum. In this paper, starting with the rationale of cognitive communication, we present two different coexistence scenarios in the context of satellite cognitive communication. We then present the current status of spectrum regulation in the context of Cognitive Radio (CR) and the relevant decisions of World Radio Conference 2012 (WRC-12). Finally, we present the technical aspects and regulatory challenges of this technology and provide some suggestions from research, industrial and regulatory perspectives

Redes 5G: una revisión desde las perspectivas de arquitectura, modelos de negocio, ciberseguridad y desarrollos de investigación

5G technology is transforming our critical networks, with long-term implications. Since 5G is transitioning to a purely software-based network, potential improvements will be software updates, like how smartphones are upgraded. For the global enterprise, the 5G arrival would be disruptive. Long-awaited solutions to various flaws in critical networking systems will arise due to 5G network adoption. Furthermore, the shortcomings of technology in contributing to business growth and success would be turned on their heads. The more complicated part of the actual 5G race is retooling how we protect the most critical network of the twenty-first century and the ecosystem of devices and applications that sprout from that network due to cyber software vulnerabilities. The new technologies enabled by new applications running on 5G networks have much potential. However, as we move toward a connected future, equal or more attention should be paid to protecting those links, computers, and applications. We address critical aspects of 5G standardization and architecture in this article. We also provide a detailed summary of 5G network business models, use cases, and cybersecurity. Furthermore, we perform a study of computer simulation methods and testbeds for the research and development of potential 5G network proposals, which are elements that are rarely addressed in current surveys and review articles.La tecnología 5G está transformando nuestras redes críticas, con implicaciones a largo plazo. Dado que 5G está en transición a una red puramente basada en software, las mejoras potenciales serán las actualizaciones de software, como la forma en que se actualizan los teléfonos inteligentes en la actualidad. Para la empresa global, la llegada de 5G sería disruptiva. Las soluciones largamente esperadas para una variedad de fallas en los sistemas clave de networking surgirán debido a la adopción de la red 5G. Además, las deficiencias de la tecnología en términos de contribuir al crecimiento empresarial y al éxito se pondrán de cabeza. La parte más complicada de la carrera 5G real es reestructurar la forma en que protegemos la red más crítica del siglo XXI y el ecosistema de dispositivos y aplicaciones que surgen de esa red debido a las vulnerabilidades cibernéticas del software. Las nuevas tecnologías habilitadas por las nuevas aplicaciones que se ejecutan en redes 5G tienen mucho potencial. Sin embargo, a medida que avanzamos hacia un futuro conectado, se debe prestar igual o mayor atención a la protección de esos enlaces, computadoras y aplicaciones. En este artículo se abordan los aspectos clave de la estandarización y la arquitectura 5G. También se proporciona un resumen detallado de los modelos comerciales de redes 5G, casos de uso y ciberseguridad. Además, se realiza un estudio de métodos de simulación por computadora y bancos de pruebas para la investigación y el desarrollo de posibles propuestas de redes 5G, que son elementos que rara vez se abordan en estudios y artículos de revisión actuales.Facultad de Informátic