80 research outputs found

    M-Business: Economy Driver or a Mess?

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    Reports about mobile wireless technology in the media may be confusing. While we know that the telecommunication industry is in distress, we also observe a phenomenal, indeed unprecedented explosion of the use of mobile wireless devices and services all over the globe. This paper presents a balanced introduction to wireless technology including devices, mobile operating systems, and communication protocols. It discusses standardization efforts, technology evolution paths, and several new and potentially disruptive technologies, some still in the research stage. The paper lists leading global wireless service providers in terms of the number of domestic subscribers and presents an analysis of the six U.S. national operators including their strengths and weaknesses. Only four of them are profitable now. Although the consumer market currently dictates technology evolution, several examples of successful business applications of wireless mobile technology are presented. Finally, the question presented in the title is addressed

    Wireless Communications: Myths and Reality

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    The use of wireless communications and computing is growing quickly, and wireless technologies are an active area of research and application. Many myths exist about different aspects of wireless computing. The purpose of this article is to examine the more prominent popular beliefs in this area. We address these beliefs using a framework consisting of three dimensions: technology, business, and society. For technology, wireless\u27 limited bandwidth and its effect on new wireless applications and services are discussed. For business, the anticipated revenue opportunities of Wi-Fi and mobile e-commerce are addressed. For society, issues of wireless security and its effect on wireless adoption are examined. Based on these examinations, we propose research directions along each dimension

    Spectrum Policy and Management

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    This project provides an examination of the FCC’s policies towards spectrum reallocation. The project examines the National Broadband Plan and how the FCC has approached the goals described within it. The demand for broadband communications has increased dramatically in recent years and has resulted in a predicted spectrum deficit in the near future. In addition to a number of spectrum auctions and their winners the project examines how the redistribution of spectrum impacts the broadband community. The project also provides an examination of spectrum reallocation and policy in other countries, to provide a broader view of spectrum policy. Finally the project examines new spectrum technologies and spectrum usage policies to further examine how the US’s spectrum policies should evolve

    InfoTech Update, Volume 13, Number 5 September/October 2004

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    https://egrove.olemiss.edu/aicpa_news/5006/thumbnail.jp

    Tavarua : a mobile telemedicine system using WWAN striping

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    Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.Includes bibliographical references (p. 69-78).Tavarua is a platform designed to support mobile telemedicine systems over wireless wide area networks, WWANs. It utilizes network striping and other complementary techniques to send uni-directional near real time video and audio data streams from a imobile node to a stationary location. The key technical challenge is transmitting high-bandwidth, loss-sensitive data over multiple low-bandwidth, lossy channels. We overcome these challenges using dynamic adjustment of the encoding parameters and a novel video encoding technique (grid encoding) that minimizes the impact of packet losses. Using five WWAN interfaces, our system reliably and consistently transmits audio and diagnostic quality video, with median PSNR values that range from 33.716dB to 36.670dB, with near real-time latencies. We present a study of the characteristic behavior of WWANs, and a description of our system architecture based in part on the lessons gleaned from that study. Through a set of experiments where we transmit video and audio data from a moving vehicle we evaluate the system, focusing on consistency, reliability, and the quality of the audio and video streams. These experiments demonstrate that we can transmit high quality video and audio in varying conditions and even in the presence of hardware failures.by Jennifer Carlisle.S.M

    On the development of Voice over IP

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    This record of study documents the experience acquired during my internship at Sonus Networks, Inc. for the Doctor of Engineering Program. In this record of study, I have surveyed and analyzed the current standardization status of Voice over Internet Protocol (VoIP) security and proposed an Internet draft on secure retargeting and response identity. The draft provides a simple and comprehensive solution to the response identity, call recipient identity and intermediate server retargeting problems in the Session Initiation Protocol (SIP) call setup process. To support product line development and enable product evolution in the quickly growing VoIP market, I have proposed a generic development framework for SIP application servers. The common and open architecture of the framework supports multiple products development and facilitates integration of new service modules. The systematical reuse of proven software design and implementation enables companies to reduce the development cost and shorten the time-to-market. As the development and diffusion of VoIP can never be isolated from the social sphere, I have investigated the current status, influence and interaction of three most important factors: standardization, market forces and government regulation on the development and diffusion of VoIP. The worldwide deregulation and market privatization have caused the transition of the standards development model. This transition in turn influences the market diffusion. Other than standardization, market forces including customer needs, the revenue pressure on carriers and vendors, competitive and economic environment, social culture and regulation uncertainties create both threats and opportunities. I have examined market drivers and obstacles in the current VoIP adoption stage, analyzed current VoIP market players and their strategies, and predicted the direction of VoIP business. The regulation creates the macro environment in which VoIP develops and diffuses. I have explored modern telecommunications regulation principles based on which government makes decisions on most current issues, including 911 support, mergers and acquisitions, interconnection obligation and leasing rights, rate structure and universal service fees

    Redes de telecomunicações móveis em Portugal: análise retrospectiva

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    Mestrado em Engenharia de Computadores e TelemáticaPortugal é um dos países da União Europeia (UE) com maior taxa de penetração do Serviço Telefónico Móvel (STM) o que o torna num dos países mais interessantes para estudos relacionados com redes e serviços M´oveis. Neste contexto os estudos de mercado para determinar a taxa de penetração de um novo serviço / tecnologia tornam-se decisivos para as empresas uma vez que podem implicar custos elevados por vezes muito difíceis de rentabilizar. Apesar de já existir algum software que permite fazer modelação do comportamento de vários operadores de telecomunicações em determinados cenários, esses modelos têm em consideração padrões de comportamento teóricos e podem não estar inteiramente adaptados à realidade de cada mercado. Este trabalho procura melhorar esses padrões de comportamento fazendo uma análise retrospectiva ao mercado do STM desde a sua introdução em Portugal, em 1989, e assim fornecer dados mais precisos às ferramentas de modelação.Portugal is one of the European Union (EU) countries with the highest penetration rate of Mobile Telecommunications Service (MTS) and that fact makes it one of the most interesting countries for conducting studies related to mobile networks and services. In this context, doing market research to determine the penetration rate of a particular new service / technology becomes crucial for companies, since it may involve high costs sometimes very difficult to monetize. Although there is already some software that models the behavior of several telecom operators in certain scenarios, these models take into account patterns of behavior based only on theory which may not be fully adapted to each market reality. This work seeks to improve those patterns of behavior by a making a retrospective market analysis of the MTS, since its introduction in Portugal in 1989 thus providing more accurate data for modeling tools

    The strategies associated with the migration of networks to 4G

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    The networks need to provide higher speeds than those offered today. For it, considering that in the spectrum radio technologies is the scarcest resource in the development of these technologies and the new developments is essential to maximize the performance of bits per hertz transmitted. Long Term Evolution optimize spectral efficiency modulations with new air interface, and more advanced algorithms radius. These capabilities is the fact that LTE is an IPbased technology that enables end-to-end offer high transmission rates per user and very low latency, ie delay in the response times of the network around only 10 milliseconds, so you can offer any realtime application. LTE is the latest standard in mobile network technology and 3GPP ensure competitiveness in the future, may be considered a technology bridge between 3G networks - current 3.5G and future 4G networks, which are expected to reach speeds of up to 1G . LTE operators provide a simplified architecture but both robust, supporting services on IP technology. The objectives to be achieved through its implementation are ambitious, first users have a wide range of added services like capabilities that currently enjoys with residential broadband access at competitive prices, while the operator will have a network fully IP-based environment, reducing the complexity and cost of the same, which will give operators the opportunity to migrate to LTE directly. A major advantage of LTE is its ability to fuse with existing networks, ensuring interconnection with the same, increasing his current coverage and allowing a data connection established by a user in the environment continue when fade the coverage LTE. Moreover, the operator has the advantage of deploying network gradually, starting initially at areas of high demand for broadband services and expand progressively in line with this. RESUMEN. Las redes necesitan proporcionar velocidades mayores a las ofertadas a día de hoy. Para ello, teniendo en cuenta que en tecnologías radio el espectro es el recurso más escaso, en la evolución de estas tecnologías y en los nuevos desarrollos es esencial maximizar el rendimiento de bits por hercio transmitido. Long Term Evolution optimiza la eficiencia espectral con nuevas modulaciones en la interfaz aire, así como los algoritmos radio más avanzado. A estas capacidades se suma el hecho de que LTE es una tecnología basada en IP de extremo a extremo que permite ofrecer altas velocidades de transmisión por usuario y latencias muy bajas, es decir, retardos en los tiempos de respuesta de la red en torno a sólo 10 milisegundos, por lo que permite ofrecer cualquier tipo de aplicación en tiempo real. LTE es el último estándar en tecnología de redes móviles y asegurará la competitividad de 3GPP en el futuro, pudiendo ser considerada una tecnología puente entre las redes 3G – 3.5G actuales y las futuras redes 4G, de las que se esperan alcanzar velocidades de hasta 1G. LTE proporcionará a las operadoras una arquitectura simplificada pero robusta a la vez, soportando servicios sobre tecnología IP. Los objetivos que se persiguen con su implantación son ambiciosos, por una parte los usuarios dispondrá de una amplia oferta de servicios añadidos con capacidades similares a las que disfruta actualmente con accesos a banda ancha residencial y a precios competitivos, mientras que el operador dispondrá de una red basada en entorno totalmente IP, reduciendo la complejidad y el costo de la misma, lo que dará a las operadoras la oportunidad de migrar a LTE directamente. Una gran ventaja de LTE es su capacidad para fusionarse con las redes existentes, asegurando la interconexión con las mismas, aumentando su actual cobertura y permitiendo que una conexión de datos establecida por un usuario en el entorno LTE continúe cuando la cobertura LTE se desvanezca. Por otra parte el operador tiene la ventaja de desplegar la red LTE de forma gradual, comenzando inicialmente por las áreas de gran demanda de servicios de banda ancha y ampliarla progresivamente en función de ésta
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