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B-ISDN connection admission control and routing strategy with traffic prediction by neural networks

Neves, Joaquim E.; Almeida, Luís B.; Leitão, Mário J.
Fonte: IEEE Press Publicador: IEEE Press
Tipo: Conferência ou Objeto de Conferência
Publicado em /05/1994 ENG
Relevância na Pesquisa
36.11%
The resource allocation in the Broadband Integrated Services Digital Network (B-ISDN) can be based in an overall network performance function described in this paper and named quality of operation. The quality of operation function is determined itself by bandwidth and quality of service functions. The traffic patterns of the quality of service for each call are predicted by neural networks. The applicability of the quality of operation function to connection admission control and call routing is proposed and supported by simulation results.

Recent improvements in the Broadband seismic networks in Portugal

Caldeira, B.; Carrilho, F.; Miranda, M.; Bezzeghoud, M.; Alves, I.; Silveira, G.; Villalonga, F.; Pena, J.A.
Fonte: EMSC Publicador: EMSC
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
26.25%
Portugal, in spite of the significant earthquake region, (e.g.: Borges et al., 2001) has been operating a limited number of broadband digital seismic instruments. The older BB seismic station in a systematic and continuous operation on the country is MTE, belonging to GEOFON and locally supported by IM, which is working since 1997. To efficiently carry out the task of develop the Broadband Portuguese seismic network, there is a collaboration between some national institutions, such as Institute of Meteorology (IM), Geophysics Center of Évora University (CGE/UE), Geophysics Center of University of Lisbon (CGUL/IGIDL) and Instituto Superior Técnico (IST), with governmental support from the National Science and Technology Foundation (Rede Nacional de Geofísica, RNG). From this collaboration we expect shortly to assist the emergence of a high quality infrastructure, significant to real-time monitoring the earthquake activity for use by governmental authorities, and of paramount importance to scientific research. The installation of this network is to be carried out in narrow connection with international institutions as GEOFON, EMSC, ROA, ORFEUS, with who we saw to establish collaborations. Data from some stations are already being exported to international data centers...

Dynamic connection provisioning in fiber-wireless access networks using tuning-based roadms

Anyuo, Shadrack Omondi
Fonte: Universidade do Algarve Publicador: Universidade do Algarve
Tipo: Dissertação de Mestrado
Publicado em //2010 ENG
Relevância na Pesquisa
26.35%
Dissertação de mest., Ciências de Computação, Faculdade de Ciências e Tecnologia, Univ. do Algarve, 2010; There has been a continuous demand for broadband services in the recent past majorly attributed to the fall in pricing of high end devices with broadband capabilities. This has brought challenges to network operators since the offered bandwidths need to match the ever increasing demand. While there has been solution for transport network to carry huge traffics through fiber optics technology, access networks have not been able to deliver this huge bandwidth to the end users. More recently, a new powerful access solution, combining the strength of both optical and wireless technologies, is under strong research. This hybrid fiber-wireless (FiWi) access solution is expected to become a powerful platform for the support of future applications and services. In this thesis, dynamic connection provisioning in FiWi access networks is discussed. In order to reduce the overall network costs in the access networks, the use of tunable reconfigurable add/drop optical multiplexers (ROADMs) at the wireless-optical interface is proposed. To achieve dynamic connection provisioning, a heuristic is proposed that minimizes the overall connection blocking probability through efficient routing & wavelength assignment and tuningbased head re-positioning at ROADMs.

Proposta de algoritmo de controle de admissão de conexões baseado em Threshold para as Redes IEEE 802.16; Proposed threshold-based connection admission control (CAC) algorithm for IEEE 802.16 networks

Soares, Claiton Luiz
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Dissertação
POR
Relevância na Pesquisa
26.38%
O padrão IEEE 802.16, também conhecido como WiMAX (Worldwide Interoperability for Microwave Access), é uma das tecnologias mais promissoras para o acesso banda larga sem fio (BWA – Broadband Wireless Access). O padrão IEEE 802.16 fornece especificações das características da camada de acesso ao meio (MAC) e física. Agrega às redes BWA algumas vantagens em relação às outras tecnologias, tal como, ampla área de cobertura, mesmo em regiões de difícil acesso ou sem qualquer infra-estrutura de rede convencional, como é o caso de algumas regiões urbanas e rurais brasileiras. O padrão IEEE 802.16 foi desenvolvido com Qualidade de Serviço (QoS) em mente. Para conseguir tal objetivo, criou-se um padrão orientado a conexão, onde as várias aplicações são diferenciadas em múltiplas classes de serviços, de acordo com os parâmetros solicitados por cada aplicação. Porém, o padrão não define como deve ser implementado o algoritmo de Controle de Admissão de Conexões (CAC – Connection Admission Control), que é um requisito fundamental para obtenção de QoS. O algoritmo CAC é responsável por admitir ou rejeitar uma solicitação de uma nova conexão dependendo dos recursos já alocados da rede. Desta forma, o CAC deve rejeitar solicitações de conexões que poderiam comprometer a QoS das conexões admitidas. Em vista disto...

Building Broadband : Strategies and Policies for the Developing World

Kim, Yongsoo; Kelly, Tim; Raja, Siddhartha
Fonte: World Bank Publicador: World Bank
Relevância na Pesquisa
36.43%
This book suggests an ecosystem approach to broadband policy that could help in the design of strategies, policies, and programs that support network expansion, have the potential to transform economies, improve the quality and range of services, enable application development, and broaden adoption among users. To identify emerging best practices to nurture this ecosystem, this volume analyzes the Republic of Korea and other leading broadband markets. It identifies three building blocks to support the growth of the broadband ecosystem: defining visionary but flexible strategies, using competition to promote market growth, and facilitating demand. An important but often neglected building block is demand facilitation. This includes raising awareness about the benefits of broadband and improving affordability and accessibility for the largest number of users. Successful countries have often focused on creating a suite of useful applications that increase the relevance of broadband to the widest base of users. Programs to mainstream information and communication technology (ICT) use in education...

Convergence : Policy and Regulatory Response

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
26.25%
In the most general sense, convergence is the integration of any traditionally segmented areas of communications systems. Convergence is happening today in Egypt, and is driven by the growth of digital media and packet data communication. In specific terms, it is essential that the Government of Egypt should create the environment in which convergence can occur without impediment. This will allow increased and risk-reduced investment in the ICTs sector, positively influence employment and industry growth, and enable Egypt to establish itself as a hub for content and services for the Arab world. Indirect impacts such as the effect on employment in the ICT sector and in the upstream content industry are more difficult to quantify without a detailed analysis of these individual industries in Egypt. However, the evidence from other countries indicates that these sectors could be significant in terms of the contribution to the economic output of the country and employment. Finally, we also considered the overall impact of the sector on economic growth in Egypt. It is not possible to isolate the specific impact of convergence on economic growth. However...

Broadband Wireless Access in Egypt

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
46.39%
This paper discusses current and future developments in wireless technology and infastructure in Egypt. One of the important regulatory decisions made in Egypt is that policy related to broadband wireless will be technology neutral. Consequently, the regulator cannot decide about which operators should use specific technologies. This approach is beneficial for the overall development of the market and deployment of networks because: It allows operators and service providers to decide on which technology or mix of technologies is best for given service and market requirements, budget outlays, and deployment scenarios. Such an approach promotes technical and economic efficiency since each service providerwill attempt to maximize revenues and their subscriber base. The flexibility allows the regulator to ensure that the market can deploy the latest technology with the least regulatory overhead. Allowing only one technology into the market place will restrict the range of choices available to consumers.

ICT Sector Policy Note for Panama : Enabling Inclusive Development through Information and Communications Technologies

World Bank
Fonte: Banco Mundial Publicador: Banco Mundial
EN_US
Relevância na Pesquisa
36.54%
The Government of Panama and the private sector recognize the importance of information and communications technology (ICT) as an enabler of national development. This ICT sector policy note seeks to identify opportunities and challenges for growth of the ICT sector in Panama, particularly on rural access to broadband services and on cybersecurity, and potential for spillover impacts across other sectors. It provides a brief overview of the ICT sector in Panama and outlines a series of strategic actions and recommendations aimed at leveraging ICT as an engine of growth by targeting connectivity infrastructure, policies, regulation, e-Services, public data, and skills. The report is organized as follows: section one presents ICT sector in the economy. Section two deals with offer for connectivity. Section three presents demand. Section four describes the sector status from the cybersecurity point of view. Based on these analyses, section five identifies challenges that are hindering the growth of the industry, and section six presents policy options to overcome them. Finally...

A Sector Assessment : Accelerating Growth of High-Speed Internet Services in Azerbaijan

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
26.62%
Azerbaijan s development at the beginning of the XXI century is characterized by the great success story of its petroleum industry, which has propelled Azerbaijan to the level of the most rapidly growing economies in Europe and Central Asia. While oil and gas reserves are finite and their extraction and transportation is largely impacted by exogenous factors the Government of Azerbaijan has recently focused its policies on economic diversification, which, among others, prioritizes public investment spending to boost the information and communication technologies (ICT) sector. It is envisaged that by 2020 Azerbaijan s ICT sector should become one of the main contributors to the non-oil GDP and should facilitate country s transition into the knowledge economy. Telecommunications liberalization, modernization and extension of the national telecom infrastructure, implementation of e-government, and other sector-specific policies have helped stimulate the growth of the local ICT sector which since 2005 has been expanding at an average rate of 25-30 percent. The telecom industry...

Broadband in Russia

Rossotto, Carlo Maria; Gelvanovska, Natalija; Hohlov, Yuri; Maciule, Vaiva; Shaposhnik, Sergei
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
46.67%
It is widely recognized that broadband is of fundamental importance to the social and economic development of a nation. The focus of the paper is on infrastructure-related actions; measures to stimulate demand for broadband are, therefore, only marginally addressed. This paper aims to provide a platform for debate with the Russian counterparts in the sector, and to discuss the measures needed to develop broadband in support of actions aimed at economic growth. This paper examines the broadband market in Russia and preconditions for its sustainable development. It begins by presenting arguments demonstrating the importance of broadband to the overall economic development of Russia, including from the perspective of diversification of the economy and new job creation. The paper benchmarks Russia s broadband performance with Organization of Economic Cooperation and Development (OECD) comparators, as well as with other nations leading the way in broadband diffusion. The paper takes stock of the existing broadband market structure in Russia and its main players as they stand today...

Multimode fibre broadband access and self-referencing sensor networks

Sánchez Montero, David
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: Tese de Doutorado Formato: application/pdf
ENG
Relevância na Pesquisa
36.19%
Future Internet Access technologies are supposed to bring us a very performing connection to the main door of our homes. At the same time, new services and devices and their increase use will require data transfers at speeds exceeding 1Gbps inside the building or home at the horizon 2012. Both drivers lead to the deployment of a high-quality, futureproof network inside buildings and homes. This environment may end up taking advantage of optical cabling solutions as an alternative to more traditional copper or pure wireless approaches. Related to this latter fact, the objectives of this work are: • The achievement of a full convergence scenario between optical networks from the telecommunication services providers to the end users underscores the necessity of accurate and realistic fibre models in assessing the performance of broadband access networks with the premises of high-capacity and total compatibility. Silicabased MMFs and PF GIPOFs are the most promising candidates for such a convergence within the in-building/home scenario. Contributions to a better understanding of the possibilities of signal transmission outside the baseband of such fibres are investigated, in order to extend their capabilities, together with the evaluation of current fibre frequency response theoretical models by means of an extensive set of measurements. • The achievement of a full convergence scenario between optical networks from the telecommunication services providers to the end users is also contingent on research and development in the field of optical fibre sensors...

Sri Lanka; Innovation, ICT and Competitiveness

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Report; Economic & Sector Work; Economic & Sector Work :: Other Infrastructure Study
ENGLISH; EN_US
Relevância na Pesquisa
26.19%
Recent history around the world has revealed that ICT can play a crucial role in economic and social development of societies at all levels of development. ICT improves communication and the exchange of knowledge and information necessary for development processes. In other words, ICT has revolutionized the way the society, businesses, and the government interacts, working procedures and processes, as well as product innovations. ‘As an accelerator, driver, multiplier, and innovator, ICT is a powerful if not indispensable tool in the massive scaling up and inter-linkages of development interventions and outcomes.’ Policy makers in Sri Lanka, like those around the world, are concerned with ensuring that the new drivers of competitiveness are a part of the development strategy. However, Sri Lanka’s first mover advantage in opening and transforming its economy has placed it in a fortuitous position of having the luxury to take a holistic and comprehensive approach to ICT development. Such a strategic approach can at once build on past strengths...

Evaluation of Former Yugoslav Republic of Macedonia's Wi-Fi Kiosk Program

Gelvanovska, Natalija; Viatchaninova, Ievgeniia; Saliu, Artan
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Working Paper; Publications & Research; Publications & Research :: Working Paper
ENGLISH; EN_US
Relevância na Pesquisa
26.36%
This white paper has been prepared by World Bank s Transport and Information and Communication Technologies (ICT) Global Practice at the request of the MIOA . Delivery of the White Paper is part of a wider package of technical assistance by the World Bank to the Government of FYR Macedonia. The paper starts off by giving an overview of the state of telecom development in rural FYR Macedonia from the standpoint of affordability and availability of the commercial broadband Internet access services for the less advantaged groups of the population. The next section describes the Wi-Fi Kiosk Project outlining its scope, aim, and implementation process while bringing forward publics experiences with respect to the Wi-Fi kiosk use. This section also examines technical parameters related to the Internet usage and demonstrates the problematic of the kiosk maintenance in the remote and rural areas. Section five references specific policy and regulatory measures designed by different government stakeholders with a goal to analyse the approach which has been chosen to ensure availability of the fixed and (or) mobile broadband Internet in the rural areas of the country. The white paper concludes with a set of observations and recommendations aiming to address the sustainability of the results achieved by the Wi-Fi Kiosk Project and to offer next steps to increase rural connectivity in FYR Macedonia.

Quality of Service Monitoring: Performance Metrics Across Proprietary Content Domains

Donahue, Hugh Carter; O'Donnell, Sean; Ferrigno-Stack, Josephine
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 121341 bytes; application/pdf
EN_US
Relevância na Pesquisa
26.47%
We propose a quality of service (QoS) monitoring program for broadband access to measure the impact of proprietary network spaces. Our paper surveys other QoS policy initiatives, including those in the airline, and wireless and wireline telephone industries, to situate broadband in the context of other markets undergoing regulatory devolution. We illustrate how network architecture can create impediments to open communications, and how QoS monitoring can detect such effects. We present data from a field test of QoS-monitoring software now in development. We suggest QoS metrics to gauge whether information "walled gardens" represent a real threat for dividing the Internet into proprietary spaces. To demonstrate our proposal, we are placing our software on the computers of a sample of broadband subscribers. The software periodically conducts a battery of tests that assess the quality of connections from the subscriber's computer to various content sites. Any systematic differences in connection quality between affiliated and non-affiliated content sites would warrant research into the behavioral implications of those differences. If, however, the data shows that there are no chronic biases in connection quality, then it would be fair to conclude that the walls on the garden are low enough not to be detrimental to public communications. QoS monitoring is timely because the potential for the Internet to break into a loose network of proprietary content domains appears stronger than ever. Recent court rulings and policy statements suggest a growing trend towards relaxed scrutiny of mergers and the easing or elimination of content ownership rules. This policy environment could lead to a market with a small number of large...

Performance Analysis of Connection Admission Control Scheme in IEEE 802.16 OFDMA Networks

Bouchti, Abdelali El; Kafhali, Said El; Haqiq, Abdelkrim
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/08/2013
Relevância na Pesquisa
26.21%
IEEE 802.16 OFDMA (Orthogonal Frequency Division Multiple Access) technology has emerged as a promising technology for broadband access in a Wireless Metropolitan Area Network (WMAN) environment. In this paper, we address the problem of queueing theoretic performance modeling and analysis of OFDMA under broad-band wireless networks. We consider a single-cell IEEE 802.16 environment in which the base station allocates subchannels to the subscriber stations in its coverage area. The subchannels allocated to a subscriber station are shared by multiple connections at that subscriber station. To ensure the Quality of Service (QoS) performances, a Connection Admission Control (CAC) scheme is considered at a subscriber station. A queueing analytical framework for these admission control schemes is presented considering OFDMA-based transmission at the physical layer. Then, based on the queueing model, both the connection-level and the packet-level performances are studied and compared with their analogues in the case without CAC. The connection arrival is modeled by a Poisson process and the packet arrival for a connection by a two-state Markov Modulated Poisson Process (MMPP). We determine analytically and numerically different performance parameters...

Performance Analysis and Special Issues of Broadband Strategies in the Computer Communication

Ahamed, S. S. Riaz; Mahesh, D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 23/01/2010
Relevância na Pesquisa
26.29%
Broadband communications consists of the technologies and equipment required to deliver packet-based digital voice, video, and data services to end users. Broadband affords end users high-speed, always-on access to the Internet while affording service providers the ability to offer value-added services to increase revenues. Due to the growth of the Internet, there has been tremendous buildout of high-speed, inter-city communications links that connect population centers and Internet service providers (ISPs) points of presence (PoPs) around the world. This build out of the backbone infrastructure or core network has occurred primarily via optical transport technology. Broadband access technologies are being deployed to address the bandwidth bottleneck for the "last mile," the connection of homes and small businesses to this infrastructure. One important aspect of broadband access to the home is that it allows people to telecommute effectively by providing a similar environment as when they are physically present in their office: simultaneous telephone and computer access, high-speed Internet and intranet access for e-mail, file sharing, and access to corporate servers.; Comment: 16 pages

Social Network Theory, Broadband and the World Wide Web

Sgroi, Daniel
Fonte: Universidade de Cambridge Publicador: Universidade de Cambridge
Formato: 352447 bytes; application/pdf; application/pdf
EN_GB
Relevância na Pesquisa
36.45%
This paper aims to predict some possible futures for the World Wide Web based on several key network parameters: size, complexity, cost and increasing connection speed thorough the uptake of broadband technology. This is done through the production of a taxonomy specifically evaluating the stability properties of the fully-connected star and complete networks, based on the Jackson and Wolinsky (1996) connections model modified to incorporate complexity concerns. We find that when connection speeds are low neither the star nor complete networks are stable, and when connection speeds are high the star network is usually stable, while the complete network is never stable. For intermediate speed levels much depends upon the other parameters. Under plausible assumptions about the future, we find that the Web may be increasingly dominated by a single intermediate site, perhaps best described as a search engine.

BROADBAND INTERNET: A PROSPECTIVE EXPLORATORY STUDY ON ITS PENETRATION, CONNECTION TECHNOLOGIES, AND IMPACTS ON BRAZIL IN 2020; INTERNET BANDA LARGA: UM ESTUDO PROSPECTIVO EXPLORATÓRIO SOBRE A SUA PENETRAÇÃO, TECNOLOGIAS DE CONEXÃO E IMPACTOS NO BRASIL EM 2020 DOI: 10.5773/rai.v9i2.675

Spers, Renata Giovinazzo; Wright, James Terence Coulter; Silva, Antonio Thiago Benedete
Fonte: Universidade de São Paulo. Economia, Administração e Contabilidade Publicador: Universidade de São Paulo. Economia, Administração e Contabilidade
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 04/07/2012 POR
Relevância na Pesquisa
36.49%
This study aimed to explore the evolution of broadband Internet penetration in Brazil in 2020 and the impacts on the population and the Brazilian economy. The Delphi Method of consultation with experts was used, in which 98 respondents in Round 1 and 72 respondents in Round 2 participated. The results indicate that there will be an increase in broadband penetration in all economic sectors. Such expansion will however depend on the lower cost of services. According to 60% of specialists, the cost of broadband Internet will be a critical factor for the expansion of penetration. The technology that will have more growth in broadband Internet connections by 2020, indicated by 33% of specialists, will be "Connecting via cable modem or wireless (offered by cable TV operators)," followed by "Connection via WiMAX networks," with 31% of predictions. As for 69% of specialists, the main impact on the economy by 2020 will be the increase of the Gross Domestic Product of Brazil, and the principal impacts of broadband Internet penetration in the Brazilian population will be the "Increase of Productivity of Individuals,” as indicated by 49% of experts, and "Improving the Quality of Life," indicated by 46%.; Esta pesquisa buscou prospectar a evolução da penetração da internet banda larga no Brasil em 2020 e os impactos na população e na economia brasileira. Para tanto...

Stimulating Broadband Adoption in Delaware: A Planning Tool

Homsey, Andrew; Patterson, Theodore; O'Boyle, Todd
Fonte: Universidade de Delaware Publicador: Universidade de Delaware
Tipo: Outros
EN_US
Relevância na Pesquisa
36.43%
published in coordination with and funded through the Delaware Department of Technology and Information; In  mid-­‐December  2009,  the  state  of  Delaware  was  awarded  funds  to  research  and  publish   broadband  options  for  its  citizens.  Governor  Jack  Markell  designated  the  Department  of   Technology  and  Information  (DTI)  as  the  agency  to  receive,  apply,  and  implement  the   funds,  according  to  the  guidelines  and  mandates  of  the  National  Telecommunications  and   Information  Administration  (NTIA).     In  2010  the  broadband-­‐mapping  portion  of  this  program  was  initiated  by  DTI,  consisting  of   data  collection,  the  development  of  a  statewide  broadband-­‐availability  map,  transmission   of  those  data  to  NTIA  for  the  development  of  its  national  broadband  map,  and  the  long-­‐ term  maintenance  of  these  data  by  the  state.    The  University  of  Delaware’s  Institute  for   Public  Administration  (IPA)  is  assisting  DTI  with  project-­‐data  collection...

Speed 2.0. Evaluating access to universal digital highways

Ahfeldt, Gabriel M.; Koutroumpis, Pantelis; Valletti, Tommaso
Fonte: Spatial Economics Research Centre, The London School of Economics and Political Science Publicador: Spatial Economics Research Centre, The London School of Economics and Political Science
Tipo: Monograph; NonPeerReviewed Formato: application/pdf
Publicado em /07/2014 EN
Relevância na Pesquisa
26.47%
This paper shows that having access to a fast Internet connection is an important determinant of capitalization effects in property markets. We combine microdata on property prices in England between 1995 and 2010 with local availability of Internet broadband connections. Rich variation in Internet speed over space and time allows us to estimate the causal effect of broadband speed on property prices. We find a significantly positive effect, but diminishing returns to speed. Our results imply that an upgrade from narrowband to a high-speed first generation broadband connection (offering Internet speed up to 8 Mbit/s) could increase the price of an average property by as much as 2.8. A further increase to a faster connection (offering speeds up to 24 Mbit/s) leads to an incremental price effect of an additional 1. We decompose this effect by income and urbanization, finding considerable heterogeneity. These estimates are used to evaluate proposed plans to deliver fast broadband universally. We find that increasing speed and connecting unserved households passes a cost-benefit test in urban and some suburban areas, while the case for universal delivery in rural areas is not as strong.