80 research outputs found

    The American University in the Digital Age (2.1)

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    Second International Conference on Asynchronous Learning Networkshttp://deepblue.lib.umich.edu/bitstream/2027.42/89414/1/1996_Sloan_Talk_2.1.pd

    The American University in the Digital Age

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    Second International Conference on Asynchronous Learning Networkshttp://deepblue.lib.umich.edu/bitstream/2027.42/89411/1/1996_Sloan_Talk.pd

    Analysis of GPRS Limitations

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    The General Packet Radio Service (GPRS) is a new standard for mobile data communications, which is implemented under the existing infrastructure of Global System for Mobile Communications (GSM). The promise capability of handling Internet Protocol traffic enables instant and constant connection to global network regardless of location and time. With its packet-based nature, the new technology facilitates new applications in wireless communications that have not been available previously. Nonetheless, there are numbers of limitations that have to be taken into consideration b~fore this technology can be implemented commercially. Despite all arguments and challenges, the GPRS system is here to stay and evolving towards the third generation mobile communications. This report covers the background of the GPRS and discusses the issues involved in implementing this current technology besides considering the deployment of third generation networks beyond GPRS

    Capture Knowledge with Object-Process Modeling - a systems engineering approach

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    To increase the efficiency of the product development process at Volvo Car Group, knowledge accumulation is central in the early strategy and concept phase. Within the department for Research and Development, the unit responsible for powertrain engineering desires a process to document system interfaces, in order to reuse what they do already know in new applications. This thesis presents a process how to capture systems knowledge; i.e. interactions within system structure, functions and behavior with the use of object-process oriented modeling. Included in the process is also ideas presented how to manage and maintain as well as interpret and reuse captured knowledge. During the first part of the project, literature of theory and previous empiric was explored, in order to understand principles of knowledge based development and systems engineering. To identify needs of the desired process, system engineers responsible for the complete powertrain were interviewed. Thereafter, the interpreted needs were translated to a functional analysis of the desired process. A case study was conducted at different developing units across Powertrain Engineering. The purpose was to map system knowledge with object-process methodology. The result was a mapped system architecture based on the vehicle response attribute, where captured system knowledge is connected to the development phases as well as the system responsible. The object-process oriented model of the system architecture included qualitative traceability between system requirements, decomposed functions, product structure with physical interface as well as resources defining who is owner of the system knowledge. To illustrate how to interpret and make the captured system knowledge reusable, structural relations within three systems was mapped in a domain mapping matrix, which is a matrix mapping the dependencies between two data types. In this case requirements and functions, as well as functions and hardware components

    Techno-economic valuation of mobile communications scenarios

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    Valuation of large projects on new communications technologies is a challenging task. Major investments are required to spread out technology and services, the characteristics of which are still largely unknown. A balanced view is needed on capabilities of the technologies, market demand, and relevant value network actors and their economies. In this dissertation, comprehensive techno-economic modelling of these aspects will be introduced for valuation of selected business scenarios. The research framework is mobile data services and business architectures in the advent of new technologies, like UMTS (Universal Mobile Telecommunications System), WLAN (Wireless Local Area Network) and WiMAX (Worldwide Interoperability for Microwave Access). The techno-economic method in this context comprises the modelling of a large set of technology, market and other factors in relation to the business operations of the analysed market actors. The many uncertainties concerning future service innovations and market development set demands on scenario creation and parameter estimation. Traditional techno-economic investment project calculation is not enough. This study gives devices for strategic decision making by analysing three different technology transitions: The modelling of Western-European incumbent operator business starting from the early 2000's indicated that the UMTS deployment should be started without delay to maximise the long-term profits from the acquired licenses, contrary to looking for short-term investment payoffs that was prevalent after the telecommunications downturn. Results also show that the emerging WLAN technology would not become a substitute for UMTS, but the public WLAN will complement the UMTS based business architecture. Modelling of the upcoming mobile WiMAX in comparison to UMTS path indicated that the mobile WiMAX cannot challenge the UMTS, as the latter one offers a better business case for the key actors. In the last transition, techno-economic delta analysis was used to quantify the benefits from the fixed-mobile convergence. The main enhancements to the techno-economic method are first the extensive classification of advanced mobile services and related modelling of service diffusion, usage patterns, capacity requirements and revenues. The second contribution is to improve the analysis of service usage in relation to technology characteristics by integrating an end-user model that gives the demand and revenue potential of each service type, per user segment and utilised technology. A novelty is also the separation of network provisioning and service provisioning part of the business architecture into separate but interlinked models. The fourth contribution to the method is the application of real options method on large communications technology deployment projects, solving option modelling problems due to the complex dependencies of the project value on the investment timing. The introduced method starts from ordinary expected cash flow valuation, but adds to that the option value related to specific flexibility in the project

    Resource management for virtualized networks

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    Network Virtualization has emerged as a promising approach that can be employed to efficiently enhance the resource management technologies. In this work, the goal is to study how to automate the bandwidth resource management, while deploying a virtual partitioning scheme for the network bandwidth resources. Works that addressed the resource management in Virtual Networks are many, however, each has some limitations. Resource overwhelming, poor bandwidth utilization, low profits, exaggeration, and collusion are types of such sort of limitations. Indeed, the lack of adequate bandwidth allocation schemes encourages resource overwhelming, where one customer may overwhelm the resources that supposed to serve others. Static resource partitioning can resist overwhelming but at the same time it may result in poor bandwidth utilization, which means less profit rates for the Internet Service Providers (ISPs). However, deploying the technology of autonomic management can enhance the resource utilization, and maximize the customers’ satisfaction rates. It also provides the customers with a kind of privilege that should be somehow controlled as customers, always eager to maximize their payoffs, can use such a privilege to cheat. Hence, cheating actions like exaggeration and collusion can be expected. Solving the aforementioned limitations is addressed in this work. In the first part, the work deals with overcoming the problems of low profits, poor utilization, and high blocking ratios of the traditional First Ask First Allocate (FAFA) algorithm. The proposed solution is based on an Autonomic Resource Management Mechanism (ARMM). This solution deploys a smarter allocation algorithm based on the auction mechanism. At this level, to reduce the tendency of exaggeration, the Vickrey-Clarke-Groves (VCG) is proposed to provide a threat model that penalizes the exaggerating customers, based on the inconvenience they cause to others in the system. To resist the collusion, the state-dependent shadow price is calculated, based on the Markov decision theory, to represent a selling price threshold for the bandwidth units at a given state. Part two of the work solves an expanded version of the bandwidth allocation problem, but through a different methodology. In this part, the bandwidth allocation problem is expanded to a bandwidth partitioning problem. Such expansion allows dividing the link’s bandwidth resources based on the provided Quality of Service (QoS) classes, which provides better bandwidth utilization. In order to find the optimal management metrics, the problem is solved through Linear Programming (LP). A dynamic bandwidth partitioning scheme is also proposed to overcome the problems related to the static partitioning schemes, such as the poor bandwidth utilization, which can result in having under-utilized partitions. This dynamic partitioning model is deployed in a periodic manner. Periodic partitioning provides a new way to reduce the reasoning of exaggeration, when compared to the threat model, and eliminates the need of the further computational overhead. The third part of this work proposes a decentralized management scheme to solve aforementioned problems in the context of networks that are managed by Virtual Network Operators (VNOs). Such decentralization allows deploying a higher level of autonomic management, through which, the management responsibilities are distributed over the network nodes, each responsible for managing its outgoing links. Compared to the centralized schemes, such distribution provides higher reliability and easier bandwidth dimensioning. Moreover, it creates a form of two-sided competition framework that allows a double-auction environment among the network players, both customers and node controllers. Such competing environment provides a new way to reduce the exaggeration beside the periodic and threat models mentioned before. More important, it can deliver better utilization rates, lower blocking, and consequently higher profits. Finally, numerical experiments and empirical results are presented to support the proposed solutions, and to provide a comparison with other works from the literature

    Data Driven Network Design for Cloud Services Based on Historic Utilization

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    In recent years we have seen a shift from traditional networking in enterprises with Data Center centric architectures moving to cloud services. Companies are moving away from private networking technologies like MPLS as they migrate their application workloads to the cloud. With these migrations, network architects must struggle with how to design and build new network infrastructure to support the cloud for all their end users including office workers, remote workers, and home office workers. The main goal for network design is to maximize availability and performance and minimize cost. However, network architects and network engineers tend to over provision networks by sizing the bandwidth for worst case scenarios wasting millions of dollars per year. This thesis will analyze traditional network utilization data from twenty-five of the Fortune 500 companies in the United States and determine the most efficient bandwidth to support cloud services from providers like Amazon, Microsoft, Google, and others. The analysis of real-world data and the resulting proposed scaling factor is an original contribution from this study

    Optimization of the methodology of configuration of mobile communication networks

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    The mobile communication network has been growing quickly, and the mobile network maintenance is becoming more complex, in performance, network coverage, energy, time consuming and expensive. The telecommunication service provider and mobile network telecommunication operator worries to what is the better methodology to optimizing a mobile network configuration and to improve the most efficient operation and functionality, to increase a superior performance in technical aspect (Create, and integrate new network planning in hardware and software level), economic aspect (cost reduction in maintenance) and environmental aspect (use of renewable energy through solar panels or wind power system). The work developed in this dissertation aims to propose an optimization of methodology of configuration of mobile communication network and build an automated configuration system in different technology (GSM, UMTS and LTE) to provide a good quality and improvement in its architecture to meet the requirement for a large number of services or application through distinct means transmission and using technology appropriate with a new generation of hardware to reach certain area in a Base Station Transmition (BTS) and a Radio Network Controller (RNC) that permit configure and integrated hardware and software issues in distinct networks technology (GSM, UMTS and LTE).A rede de comunicação móvel tem crescido rapidamente e ficando cada vez mais complexa, sendo cada vez mais complicado melhorar o desempenho, a cobertura, a eficiência energética e ao mesmo tempo aumentar o numero de utilizadores e serviços. O provedor de serviços de telecomunicações e a operadora de rede móvel têm de se preocupar em optimizar de forma a garantir a melhor configuração de rede móvel tendo em vista melhorar a operação e funcionalidade, a fim de esta ser mais eficiente, no seu desempenho. Relativamente aos aspectos técnicos (Criar novo planeamento e integrar a uma rede ao nível hardware e de software), aspecto econômico (redução de custo na manutenção) e aspecto ambiental (uso de energia renovável, quer através de painéis solares como de sistemas eólicos). O trabalho desenvolvido nesta dissertação visa propor uma otimização da metodologia de configuração das redes de comunicação móveis e construir um sistema de configuração automatizado em diferentes tecnologias (GSM, UMTS e LTE), para garantir os mais altos padrões de qualidade e atender a exigência de um grande número de serviços ou aplicações através de diferentes meios de transmissão e uso de tecnologia apropriada com uma nova geração de hardware para atingir determinada área em uma Estação de Transmissão de Base (BTS) e numa Rede de Controlador de Rádio (RNC) que permitem configurar e integrar diversos tipos de hardware e software em tecnologia de diferentes redes (GSM, UMTS e LTE)

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

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    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
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