Diseño de una red X.25 sobre la red IP para la conexión de centrales de conmutación digital

La aparición de nuevas tecnologías en las redes de datos, han dado origen a modelos de red que brindan elevados índices de calidad y nuevas prestaciones a los clientes. Entre estos nuevos modelos se tiene a la Red IP, la cual es una red de transmisión de datos basada en el uso del protocolo IP (Internet Protocol) ampliamente difundido en Internet. La red IP esta físicamente implementada con equipos ruteadores, nodos conmutadores, servidores y aplicaciones de software, orientada a dar conectividad a las redes y computadoras que trabajan bajo este protocolo. El núcleo de la red esta formado por una malla ATM de alto rendimiento, la cual brinda el transporte de los paquetes IP entre los diferentes nodos de acceso. Actualmente las plataformas de gestión de tráfico y la de operación y mantenimiento centralizado de las centrales telefónicas de conmutación digital a nivel nacional están basadas en conexiones X.25 a cada una de las centrales. Estas conexiones dedicadas generan altos costos de alquiler, operación y mantenimiento para la administración. El presente trabajo tiene como objetivo usar la Red IP como medio de transporte para una red de conmutación de paquetes X.25 utilizada por las plataformas de gestión y mantenimiento centralizado para la conexión a las centrales telefónicas de conmutación digital. Lo que se va a diseñar es una solución que va a reemplazar el medio de transporte de la red X.25 por un medio de transporte IP. Este trabajo se divide en dos partes principales: En la Primera Parte se hace un breve marco teórico sobre la Redes X.25 e IP, también se presenta como esta estructurada e implementada la Red IP en el Perú, luego se explica en detalle como están conformadas y cual es la función dentro de la administración de las plataformas de Gestión de Tráfico (SGT) y la de Operación y Mantenimiento Centralizado (EOC).Tesi

Assessing the impact of design for environment guidelines : a case study of office telephones

This research addresses a fundamental question: How much of the improvement in a product\u27s environmental performance is directly attributable to the Design for Environment (DFE) tools and guidelines, and how much results simply from other design objectives or enabling technologies? The research examines four generations of a business telephone over the last thirty years, including the current generation, which has been designed using DEE guidelines. A lifecycle assessment (LCA) and demanufacturing analysis were performed on each of the first three generations to determine various technology and non-DEE trends. This information was used to forecast the progression to a 1997 non-DEE phone. By overlaying comparable information generated by analyzing the 1997 DEE-designed phone, the true impact of DFE on the product becomes apparent. Relevant characteristics and metrics such as raw materials, energy depletion, environmental burdens, and others were used to analyze the environmental performance of the telephones. All of the trend characteristics are based on lifecycle data; consequently, LCA tools and methodologies are the basis for performing this study. Traditional LCA methodologies have been expanded to incorporate multi-lifecycle options for the product and its basic materials. In addition, techniques such as the EcoCompass, developed at Dow Europe, and Resource Productivity, as proposed by Sony, are used to compare the various generations

Internet access standards: dissemination of the Integrated Services Digital Network in Spain, 1984-2005

This article aims to narrate the birth and evolution of the Integrated Services Digital Network (ISDN) in Spain with an essentially descriptive methodology, from an interdisciplinary perspective and from varied sources. The study aims to investigate the forms of the transition from a conceptual or engineering phase to the market in a standard of Internet access and, at the same time, in the different patterns of technological innovation and the factors that motivate them. It tries to verify if the own nature of the techniques, the degree of diffusion of the previous technologies, the technological level -digitalization- and the structure of market of the telecommunications — continued existence of the monopoly of the historical operator National Telephone Company of Spain — had a significant impact on the inequality of penetration with respect to other countries. The research authorizes to conclude that a very heterogeneous combination of factors caused that leading countries in the diffusion of a technology did not achieve that leading role in the diffusion of other technologies

A Bandwidth Sharing Approach to Improve Licensed Spectrum Utilization

The spectrum of deployed wireless cellular communication systems is found to be underutilized, even though licensed spectrum is at a premium. To efficiently utilize the bandwidth left unused in a cellular system, the primary system (PRI), we propose an overlaid ad hoc secondary network (ASN) architecture, with the ASN operating over the resources left unutilized by the PRI. Our basic design principle is that the ASNoperates in a nonintrusive manner and does not interact with the PRI. In this article we present the ad hoc secondary medium access control (AS-MAC) protocol to enable PRI-SEC interoperation, address a number of technical challenges pertinent to this networking environment, and evaluate the performance of the AS-MAC. In a single-hop ASN the AS-MAC transparently utilizes 75 percent of the bandwidth left unused by the PRI, while in multihop ASNs, due to spatial reuse, the AS-MAC can utilize up to 132 percent of the idle PRI resources in our experiments

Domain-specific languages

Domain-Specific Languages are used in software engineering in order to enhance quality, flexibility, and timely delivery of software systems, by taking advantage of specific properties of a particular application domain. This survey covers terminology, risks and benefits, examples, design methodologies, and implementation techniques of domain-specific languages as used for the construction and maintenance of software systems. Moreover, it covers an annotated selection of 75 key publications in the area of domain-specific languages

ACUTA eNews May 1996, Vol. 25, No. 5

In This Issue From the President DC at a Glance Letter to FCC High-Tech Crime From ACUTA Headquarter

Keeping pace with globalisation innovation capability in Korea's telecommunications equipment industry

Korea is one of the four from the developing world to have built up substantial innovation capability in the design and manufacture of state-of-the-art telecommunications equipments. The paper undertakes a detailed review of this innovation capability and analyses its precise status during the time when the Korean economy was subject to a serious financial crisis. The paper maps out the sectoral system for innovation in the telecommunications equipment industry and measures the innovation capability in terms of a set of three separate indicators. The ensuing analysis shows that the country has built up substantial innovation capability in not just fixed telephony but also in mobile communication technologies. There has been some passage of this capability from the public research laboratory to private sector manufacturing firms. The Korean state has continued to support the public laboratory through a variety of financial grants and public technology procurement. However these traditional instruments of support are no longer valid in newer technologies such as mobile telephony. The innovation system has nevertheless achieved considerable sophistication that it is in a position to keep pace with changes in the technology frontier Key words: Innovation Capability, Korea, Telecommunications, Digital Switching systems, CDMA Mobile Telephony. JEL Classification: L630, O310, O320, O380

Technologies and policies for an evolving telecommunications sector in China

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.Includes bibliographical references (p. 107-115).by Emily Yeh.M.S