Cost-effective Information and Communication Technology (ICT) infrastructure for Tanziania

The research conducted an Information and Communication Technology (ICT) field survey, the results revealed that Tanzania is still lagging behind in the ICT sector due to the lack of an internationally connected terrestrial ICT infrastructure; Internet connectivity to the rest of the world is via expensive satellite links, thus leaving the majority of the population unable to access the Internet services due to its high cost. Therefore, an ICT backbone infrastructure is designed that exploits optical DWDM network technology, which un-locks bandwidth bottlenecks and provides higher capacity which will provide ICT services such as Internet, voice, videos and other multimedia interactions at an affordable cost to the majority of the people who live in the urban and rural areas of Tanzania. The research analyses and compares the performance, and system impairments, in a DWDM system at data transmission rates of 2.5 Gb/s and 10 Gb/s per wavelength channel. The simulation results show that a data transmission rate of 2.5 Gb/s can be successfully transmitted over a greater distance than 10 Gb/s with minimum system impairments. Also operating at the lower data rate delivers a good system performance for the required ICT services. A forty-channel DWDM system will provide a bandwidth of 100 Gb/s. A cost analysis demonstrates the economic worth of incorporating existing optical fibre installations into an optical DWDM network for the creation of an affordable ICT backbone infrastructure; this approach is compared with building a completely new optical fibre DWDM network or a SONET/SDH network. The results show that the ICT backbone infrastructure built with existing SSMF DWDM network technology is a good investment, in terms of profitability, even if the Internet charges are reduced to half current rates. The case for building a completely new optical fibre DWDM network or a SONET/SDH network is difficult to justify using current financial data

Transparent metropolitan vehicular network - design and fast prototyping methodology

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 201

Linguajem de domínio específico para configuração de dispositivos de redes

Introduction: This research is part of the project “Algorithm model for the implementation of configurations on network devices”, ascribed to the Master’s Degree of Information and Communications Sciences of the District University Francisco Jose de Caldas during the years 2015 and 2016. The detected issue is the search of configurations in network devices, which has proven to be a complex and repetitive task due to the wide variety of existent configurations. Methodology: This article presents the development of two domain-specific languages (dsl) based on mde. One is graphic: cnpGraph, and the other is textual: cnpText, as a proposed solution to the problem. Each tool generates a document with network protocols configurations required for network devices, regardless of the devices being routers or switches. Results: The tests were conducted using different scenarios and configurations, and comparing the search times through the use of domain-specific languages and conventional searches. The results show that cnpGraph and cnpText reduce in over 80 % the time used in finding the required configurations. Discussion: The main characteristic of both cnpGraph and cnpText is the possibility of increasing the amount of protocols and private brands of routers and switches, as well as associating protocols with the purpose of adding new network devices from different manufacturers and to access the necessary configuration in order to stablish every type of network.Introducción: este trabajo hace parte del proyecto “Modelo de algoritmo para implementación de configuraciones en dispositivos de redes”, adscrito a la Maestría de Ciencias de la Información y las Comunicaciones de la Universidad Distrital Francisco José de Caldas en el 2015 y 2016. El problema detectado es la búsqueda de configuraciones en dispositivos de red, la cual resulta ser una tarea compleja y repetitiva debido a la gran variedad de configuraciones existentes. Metodología: este artículo presenta el desarrollo de dos lenguajes de dominio específico (dsl) basados en mde, uno gráfico: cnpGraph, y uno textual: cnpText, como propuesta de solución al problema. Cada herramienta genera un documento con las configuraciones de los protocolos de red requeridas para los dispositivos de red, ya sean routers o switches. Resultados: las pruebas se hicieron sobre diferentes escenarios y configuraciones, comparando los tiempos de búsqueda mediante el uso de lenguajes de dominio específico y búsquedas convencionales. Los resultados mostraron que cnpGraph y cnpText reducen en más de un 80 % el tiempo necesario para encontrar las configuraciones. Conclusiones: la característica principal, tanto de cnpGraph como de cnpText, es la posibilidad de ampliación del número de protocolos y marcas de fabricantes de routers y switchess, así como la vinculación de protocolos, con el propósito de añadir nuevos dispositivos de red de diferentes fabricantes y disponer de toda la configuración necesaria para establecer cualquier tipo de red.Introdução: este trabalho faz parte do projeto “Modelo de algoritmo para implementação de configurações em dispositivos de redes”, do Mestrado de Ciências da Informação e as Comunicações da Universidade Distrital Francisco José de Caldas no ano 2015 e 2016. O problema evidenciado é a busca de configurações em dispositivos de rede, que é uma tarefa complexa e repetitiva por causa da grande variedade de configurações existentes. Metodologia: este artigo apresenta o desenvolvimento de duas linguagens de domínio específico (dsl) baseados em mde, um gráfico: cnpGraph, e um textual: cnpText, como proposta de solução ao problema. Cada ferramenta gera um documento com as configurações dos protocolos de rede requeridos para os dispositivos de rede, sejam eles routers ou switches. Resultados: os testes realizados sobre diferentes cenários e configurações, comparando os tempos de busca através do uso de linguagens de domínio específico e buscas convencionais. Os resultados mostraram que cnpGraph e cnpText reduzem em mais de 80 % o tempo requerido para achar as configurações. Conclusões: a principal característica, tanto de cnpGraph quanto de cnpText, é a possibilidade de ampliação do número de protocolos e marcas de fabricantes de routers e switchess, bem como a vinculação de protocolos, com o intuito de adicionar novos dispositivos de rede de diferentes fabricantes e dispor de toda a configuração requerida para estabelecer qualquer tipo de rede

Quantum key distribution: A networking perspective

The convergence of quantum cryptography with applications used in everyday life is a topic drawing attention from the industrial and academic worlds. The development of quantum electronics has led to the practical achievement of quantum devices that are already available on the market and waiting for their first application on a broader scale. A major aspect of quantum cryptography is the methodology of Quantum Key Distribution (QKD), which is used to generate and distribute symmetric cryptographic keys between two geographically separate users using the principles of quantum physics. In previous years, several successful QKD networks have been created to test the implementation and interoperability of different practical solutions. This article surveys previously applied methods, showing techniques for deploying QKD networks and current challenges of QKD networking. Unlike studies focusing on optical channels and optical equipment, this survey focuses on the network aspect by considering network organization, routing and signaling protocols, simulation techniques, and a software-defined QKD networking approach.Web of Science535art. no. 9

A virtual intergrated networks emulator on xen (viNex)

Network research experiments have traditionally been conducted in emulated or simulated environments. Emulators are frequently deployed on physical networks. Network simulators provide a self-contained and simple environment that can be hosted on one host. Simulators provide a synthetic environment that is only an approximation of the real world and therefore the results might not be a true re ection of reality. Recent progress in virtualisation technologies enable the deployment of multiple interconnected, virtual hosts on one machine. Virtual hosts run real network protocol stacks and therefore provide an emulated environment on a single host. The rst objective of this dissertation is to build a network emulator (viNEX) using a virtualisation platform (XEN). The second objective is to evaluate whether viNEX can be used to conduct some network research experiments. Thirdly, some limitations of this approach are identifiedComputingM. Sc. (Computer Science

Improved learning automata applied to routing in multi-service networks

Multi-service communications networks are generally designed, provisioned and configured, based on source-destination user demands expected to occur over a recurring time period. However due to network users' actions being non-deterministic, actual user demands will vary from those expected, potentially causing some network resources to be under- provisioned, with others possibly over-provisioned. As actual user demands vary over the recurring time period from those expected, so the status of the various shared network resources may also vary. This high degree of uncertainty necessitates using adaptive resource allocation mechanisms to share the finite network resources more efficiently so that more of actual user demands may be accommodated onto the network. The overhead for these adaptive resource allocation mechanisms must be low in order to scale for use in large networks carrying many source-destination user demands. This thesis examines the use of stochastic learning automata for the adaptive routing problem (these being adaptive, distributed and simple in implementation and operation) and seeks to improve their weakness of slow convergence whilst maintaining their strength of subsequent near optimal performance. Firstly, current reinforcement algorithms (the part causing the automaton to learn) are examined for applicability, and contrary to the literature the discretised schemes are found in general to be unsuitable. Two algorithms are chosen (one with fast convergence, the other with good subsequent performance) and are improved through automatically adapting the learning rates and automatically switching between the two algorithms. Both novel methods use local entropy of action probabilities for determining convergence state. However when the convergence speed and blocking probability is compared to a bandwidth-based dynamic link-state shortest-path algorithm, the latter is found to be superior. A novel re-application of learning automata to the routing problem is therefore proposed: using link utilisation levels instead of call acceptance or packet delay. Learning automata now return a lower blocking probability than the dynamic shortest-path based scheme under realistic loading levels, but still suffer from a significant number of convergence iterations. Therefore the final improvement is to combine both learning automata and shortest-path concepts to form a hybrid algorithm. The resulting blocking probability of this novel routing algorithm is superior to either algorithm, even when using trend user demands

An investigation into the use of B-Nodes and state models for computer network technology and education

This thesis consists of a series of internationally published, peer reviewed, conference research papers and one journal paper. The papers evaluate and further develop two modelling methods for use in Information Technology (IT) design and for the educational and training needs of students within the area of computer and network technology. The IT age requires technical talent to fill positions such as network managers, web administrators, e-commerce consultants and network security experts as IT is changing rapidly, and this is placing considerable demands on higher educational institutions, both within Australia and internationally, to respond to these changes

Design and performance evaluation of Wireless Multi-Protocol Label Switching (WMPLS)

Scope and Method of Study: The research presented in this document focuses on the design of a new protocol for high-speed wireless data communications. The primary goal of this new design is to overcome the limitations of its predecessors, while minimizing the needed resources and maximizing throughput and efficiency in its operations. Another important goal of the study is to provide a homogeneous protocol for wired and wireless networks in order to provide complete interoperability for overlay models and other protocols that can be designed on the basis of this work. The performance evaluation part of this document shows the areas in which improvement has been achieved over previous protocol implementations, and it also shows the areas in which further research is needed in order to improve the performance at least to the levels set by previous protocols.Findings and Conclusions: This study shows that a native wireless design and implementation of the Multi-Protocol Label Switching (MPLS) protocol provides improvements in the field of wireless data communications, providing a homogeneous platform for voice and data communication networks. The research is open for further improvements and modifications for services not contemplated in this document, and continuous developments should be conducted in order to obtain a working prototype of this proposal