Implantação do módulo de Gestão da Configuração do framework ITIL: um estudo de caso

This paper is based on the operation of one of the most used IT service management models by organizations around the world, ITIL. With the purpose of expanding knowledge in the area, the main proposal of this article is to present experiences, viewpoints, criticism and added value generated during and after the implementation of the ITIL Configuration Management module in a Brazilian public agency. As a successful case, its main objective is to measure the direct and indirect user’s satisfaction level of the proposed module, in order to explore the main benefits of an implementation based on best practice and, to propose improvements and suggestions for future implementation processes.Este trabalho se baseia no funcionamento de um dos modelos de gestão de serviços de TI mais utilizados pelas organizações de todo o mundo, o ITIL. Com o objetivo de expandir o conhecimento na área, a principal proposta deste artigo é expor experiências, pontos de vistas, críticas e valor agregado gerados durante e após a implantação do módulo de Gestão da Configuração da ITIL em um órgão público brasileiro. Por ser um caso de sucesso, o principal objetivo é mensurar o nível de satisfação do usuário direto e indireto do módulo em questão, explorando os principais benefícios de uma implantação baseada nas melhores práticas do campo, além de propor melhorias e sugestões aos processos de implantação futuros

WiMAX spectrum virtualization and network federation

Spectrum management in wireless broadband networks as regards its cost and its efficient usage has posed a huge challenge for mobile network operators. Traditionally, network operators had exclusive rights to access the band of spectrum allocated to them, but with the high price of spectrum license, it is becoming necessary to find alternative ways to use and access spectrum more efficiently. Resource virtualization is a method which has been extensively adopted in hardware computing for creating abstract versions of physical hardware resources and it has proven to be a powerful technique for customized resource provision and sharing. This idea of resource virtualization is gradually being transferred into the domain of wireless mobile network resource management but the ideas around it are still evolving. Since spectrum is an important wireless network resource, it is imperative to provide an efficient and cost effective means for the resource to be accessed and utilized. Therefore the idea of spectrum virtualization is investigated in this research as a possible solution to this problem. To expand on the notion of spectrum virtualization, this research further explores the idea of network federation. Network Federation involves the interconnection of diverse network components to be operated as a single seamless network. This will enable them share their network resources while the networks are geographically dispersed and managed by different network operators. To fully implement these concepts there is a need for a well-developed network framework. This research proposes two novel architectures for spectrum virtualization and network federation using the WiMAX (Worldwide Interoperability for Microwave Exchange) wireless broadband technology. The proposed WiMAX spectrum virtualization architecture introduces a novel entity known as the Virtual Spectrum Hypervisor (VS-Hypervisor). This VS-Hypervisor bears the responsibility of spectrum management and virtualization within the WiMAX framework. In the implementation of WiMAX network federation, the novel architecture enables the cooperative existence of multiple WiMAX base-stations having virtualization capabilities with overlapping cellular coverage areas for the purpose of sharing their spectrum resources. In this architecture, a novel federation control plane known as the Virtual Spectrum Exchange Locale (VSEL) is proposed. The VSEL facilitates the VS-Hypervisors in the federated physical base-stations to be able to negotiate and exchange spectrum between themselves to match their spectrum needs. The architectures for WiMAX spectrum virtualization and network federation was modelled and implemented using the OPNET Modeler. Results obtained validated their efficacy with respect to the effective management of the wireless network spectrum. Therefore this proposed network architectures would help network operators optimize their radio networks