IP and ATM - a position paper

This paper gives a technical overview of different networking technologies, such as the Internet, ATM. It describes different approaches of how to run IP on top of an ATM network, and assesses their potential to be used as an integrated services network

IP and ATM - current evolution for integrated services

Current and future applications make use of different technologies as voice, data, and video. Consequently network technologies need to support them. For many years, the ATM based Broadband-ISDN has generally been regarded as the ultimate networking technology, which can integrate voice, data, and video services. With the recent tremendous growth of the Internet and the reluctant deployment of public ATM networks, the future development of ATM seems to be less clear than it used to be. In the past IP provided (and was though to provide) only best effort services, thus, despite its world wide diffution, was not considered as a network solution for multimedia application. Currently many of the IETF working groups work on areas related to integrated services, and IP is also proposing itself as networking technology for supporting voice, data, and video services. This paper give a technical overview on the competing integrated services network solutions, such as IP, ATM and the different available and emerging technologies on how to run IP over ATM, and tries to identify their potential and shortcomings

Red de comunicaciones para una entidad con 2 centros de cálculo y 200 sedes

La rápida y continua expansión de Internet ha supuesto un profundo cambio en el modo de comunicación y acceso a la información digital. Esta situación ha influido, también, en las redes de comunicaciones empleadas por todo tipo de entidades (empresas, universidades, bancos, administraciones públicas…) con el surgimiento de tecnologías que facilitan el uso de Internet como medio de transmisión para establecer enlaces de datos entre sedes remotas y sus centros de procesamiento de datos. Concretamente, este trabajo se focaliza en la creación de una red privada virtual dinámica multipunto, mediante el programa de simulación gráfico de red GNS3, utilizando, para ello, una topología completamente mallada con el uso de interfaces multiacceso en combinación con técnicas de tunelizado, encaminamiento y encriptación. Además, la red emplea protocolos y tecnologías adicionales que proporcionan alta disponibilidad, políticas de calidad de servicio eficientes para permitir el reparto de latencias y caudales según el tipo de aplicación, Multicast IP, componentes de seguridad; así como herramientas para la gestión y monitorización de red

Learning tool for IPSEC with emphasis on the use of MGRE in corporate networks

Este artículo presenta la herramienta “IPsec Tools UV”, desarrollada para entender e interactuar de una manera didáctica con las transformaciones que realiza IPsec cuando usa los algoritmos MD5, SHA-1 y 3DES durante la verifcación de integridad y cifrado de un datagrama IPv4. Como ejemplo se presenta la implementación de una red corporativa usando Redes Privadas Virtuales Dinámicas Multipunto, las cuales se basan en el establecimiento de túneles dinámicos protegidos por IPsec. La herramienta fue desarrollada en Java y con el apoyo de otro programa desarrollado fue posible validar el código de los algoritmos MD5 y SHA-1 con 14 vectores de prueba especifcados en la RFC 2202. Además, para mostrar una aplicación de IPsec, se hizo el diseño, confguración, emulación y validación de tres redes privadas conectadas a través de la Internet pública utilizando el software de emulación GNS3.This paper presents a tool named “UV IPsec Tools”, developed to understand and interact in a didactic way with the transformations performed by IPsec when using the MD5, SHA-1 and 3DES algorithms for the encryption and integrity check of an IPv4 datagram. As an example, we present the implementation of a corporate network using Dynamic Multipoint Virtual Private Networks, which are based on the establishment of dynamic tunnels protected by IPSec. The tool was developed in Java and with the help of another program we developed, it was possible to validate the code for the MD5 and SHA-1 algorithms with 14 test vectors as specifed in RFC 2202. Also, to show an application on IPsec, the design, confguration, emulation and validation of three private networks connected via the public Internet using GNS3 was made.   &nbsp

Diseño y simulación de una red privada virtual multipunto dinámico 8DMVPN en internet para una empresa de Lima, Perú

En la actualidad, las empresas tienen la necesidad de interconectarse con sus sucursales y sus usuarios remotos. Para ello, este diseño DMVPN tiene como objetivo interconectar el hub Lima con spokes en el norte del país de una empresa de Lima, se utilizó el protocolo Next Hop Resolution Protocol (NHRP) que permite realizar un enmallado de red virtual entre spokes y es escalable con el tiempo. Esta solución usa los protocolos de Cisco Systems y herramientas de simulación que hace posible el desarrollo y comprobación de estas. Mediante el diseño y simulación de DMVPN se logró disminuir la trazabilidad de la red entre spokes y optimizar el tiempo de respuesta. En conclusión, esta diseño y simulación de red DMVPN, ayudará a una mejor convergencia de red mediante una red privada o pública recomendado para empresas con varias sucursales que necesitan comunicarse entre sí.Trabajo de investigaciónCampus Lima Centr

IP and ATM integration: A New paradigm in multi-service internetworking

ATM is a widespread technology adopted by many to support advanced data communication, in particular efficient Internet services provision. The expected challenges of multimedia communication together with the increasing massive utilization of IP-based applications urgently require redesign of networking solutions in terms of both new functionalities and enhanced performance. However, the networking context is affected by so many changes, and to some extent chaotic growth, that any approach based on a structured and complex top-down architecture is unlikely to be applicable. Instead, an approach based on finding out the best match between realistic service requirements and the pragmatic, intelligent use of technical opportunities made available by the product market seems more appropriate. By following this approach, innovations and improvements can be introduced at different times, not necessarily complying with each other according to a coherent overall design. With the aim of pursuing feasible innovations in the different networking aspects, we look at both IP and ATM internetworking in order to investigating a few of the most crucial topics/ issues related to the IP and ATM integration perspective. This research would also address various means of internetworking the Internet Protocol (IP) and Asynchronous Transfer Mode (ATM) with an objective of identifying the best possible means of delivering Quality of Service (QoS) requirements for multi-service applications, exploiting the meritorious features that IP and ATM have to offer. Although IP and ATM often have been viewed as competitors, their complementary strengths and limitations from a natural alliance that combines the best aspects of both the technologies. For instance, one limitation of ATM networks has been the relatively large gap between the speed of the network paths and the control operations needed to configure those data paths to meet changing user needs. IP\u27s greatest strength, on the other hand, is the inherent flexibility and its capacity to adapt rapidly to changing conditions. These complementary strengths and limitations make it natural to combine IP with ATM to obtain the best that each has to offer. Over time many models and architectures have evolved for IP/ATM internetworking and they have impacted the fundamental thinking in internetworking IP and ATM. These technologies, architectures, models and implementations will be reviewed in greater detail in addressing possible issues in integrating these architectures s in a multi-service, enterprise network. The objective being to make recommendations as to the best means of interworking the two in exploiting the salient features of one another to provide a faster, reliable, scalable, robust, QoS aware network in the most economical manner. How IP will be carried over ATM when a commercial worldwide ATM network is deployed is not addressed and the details of such a network still remain in a state of flux to specify anything concrete. Our research findings culminated with a strong recommendation that the best model to adopt, in light of the impending integrated service requirements of future multi-service environments, is an ATM core with IP at the edges to realize the best of both technologies in delivering QoS guarantees in a seamless manner to any node in the enterprise

IPv6 sobre ATM

La provisión de calidad de servicio (QoS) garantizada por parte de las redes de comunicación, en un ámbito global, es actualmente uno de principales campos de investigación, principalmente debido a la creciente importancia de aplicaciones como VoIP,..

Renegotiable VBR service

In this work we address the problem of supporting the QoS requirements for applications while efficiently allocating the network resources. We analyse this problem at the source node where the traffic profile is negotiated with the network and the traffic is shaped according to the contract. We advocate VBR renegotiation as an efficient mechanism to accommodate traffic fluctuations over the burst time-scale. This is in line with the Integrated Service of the IETF with the Resource reSerVation Protocol (RSVP), where the negotiated contract may be modified periodically. In this thesis, we analyse the fundamental elements needed for solving the VBR renegotiation. A source periodically estimates the needs based on: (1) its future traffic, (2) cost objective, (3) information from the past. The issues of this estimation are twofold: future traffic prediction given a prediction, the optimal change. In the case of a CBR specification the optimisation problem is trivial. But with a VBR specification this problem is complex because of the multidimensionality of the VBR traffic descriptor and the non zero condition of the system at the times where the parameter set is changed. We, therefore, focus on the problem of finding the optimal change for sources with pre-recorded or classified traffic. The prediction of the future traffic is out of the scope of this thesis. Traditional existing models are not suitable for modelling this dynamic situation because they do not take into account the non-zero conditions at the transient moments. To address the shortfalls of the traditional approaches, a new class of shapers, the time varying leaky bucket shaper class, has been introduced and characterised by network calculus. To our knowledge, this is the first model that takes into account non-zero conditions at the transient time. This innovative result forms the basis of Renegotiable VBR Service (RVBR). The application of our RVBR mathematical model to the initial problem of supporting the applications' QoS requirements while efficiently allocating the network resources results in simple, efficient algorithms. Through simulation, we first compare RVBR service versus VBR service and versus renegotiable CBR service. We show that RVBR service provides significant advantages in terms of resource costs and resource utilisation. Then, we illustrate that when the service assumes zero conditions at the transient time, the source could potentially experience losses in the case of policing because of the mismatch between the assumed bucket and buffer level and the policed bucket and buffer level. As an example of RVBR service usage, we describe the simulation of RVBR service in a scenario where a sender transmits a MPEG2 video over a network using RSVP reservation protocol with Controlled-Load service. We also describe the implementation design of a Video on Demand application, which is the first example of an RVBR-enabled application. The simulation and experimentation results lead us to believe that RVBR service provides an adequate service (in terms of QoS guaranteed and of efficient resource allocation) to sources with pre-recorded or classified traffic

Uma aplicação para a monitoração de atalhos MPOA Client utilizando agentes móveis

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação.Análise da jurisprudência sobre a responsabilidade civil decorrente da inscrição indevida do nome do cliente nos órgãos de proteção ao crédito (SPC e SERASA) e do protesto indevido de título de crédito. Critérios objetivos utilizados pelo Tribunal para quantificar o valor do dano extrapatrimonial

Análisis comparativo entre VPN IPSEC y DMVPN (Dynamic Multipoint Virtual Private Network) para mejorar el desempeño de redes privadas sobre internet.

Se realizó el análisis comparativo entre Red privada virtual Protocolo de Internet Seguro (VPN IPSEC) y red privada virtual multipunto dinámica (DMVPN) para mejorar el desempeño de redes privadas sobre Internet. La solución tradicional de VPN se basa en IPsec punto a punto, la cual no permite una comunicación directa entre cada sitio y depende del estado de su concentrador para garantizar la comunicación. Se evaluó una nueva técnica que elimina las conexiones punto a punto y permita la convergencia de las aplicaciones, se analiza DMVPN como una solución que permitirá mejorar el desempeño de las VPN sobre Internet. Se implementó una red de un HUB y cuatro SPOKE para la transmisión y evaluación de paquetes de datos, voz y video. Analizados los resultados de las pruebas en ambos escenarios se obtiene que en la comunicación entre SPOKES predominó en arrojar resultados favorables con una mejora del 88,8% en el retardo, 64,1% en el jitter y 84,9% en la pérdida de paquetes. Aplicando la estadística inferencial se concluye que la técnica DMVPN arroja mejores valores en los indicadores de desempeño de la red que son retardo de paquetes, jitter y paquetes perdidos, de la misma manera muestra valores de dispersión más bajos. Como propuesta se desarrolló una guía de implementación de DMVPN incluyendo todas las consideraciones que se debe aplicar en la práctica producto de las pruebas realizadas.The comparative analysis between Virtual Private Network Internet Protocol Security (VPN IPSec) and Virtual Private Network Dynamic Multipoint (DMVPN) was made to improve the performance of private networks over the Internet. The traditional VPN solution is based on IPsec point to point, which does not allow direct communication between each site and depends on the status of its concentrator to ensure the communication. A new technique was evaluated; this eliminates point-to-point connections and enables the convergence of applications. DMVPN analyzed as a solution; that will improve the performance of VPNs over the Internet. A network of one HUB and four SPOKE was implemented for the transmission and evaluation of data, voice and video packages. Analyzed the results of the tests in both scenarios, it obtained that the communication between SPOKES predominated in throwing favorable results with an improvement of 88,8% in the delay, 64,1% in the jitter and 84,9% in the loss of packages. Applying the statistics inference concluded that the DMVPN technique yields better values in the performance indicators of the network that are packet delay, jitter, and lost packets, in the same way, it shows lower dispersion values. As a proposal, a DMVPN implementation guide was developed, including all the considerations that should be applied in the practice product of the tests performed