Avaliação de dependabilidade em redes de computadores utilizando os mecanismos de modelagem analítica e análise de sensibilidade: um estudo de caso baseado em uma pequena empresa

Abstract

With the growing dependence on social and economic activities in information systems, there is great expectation regarding the availability, reliability and robustness for the computer networks underlying these systems. This expectation is due to the possibility of failures on these networks that can originate from several sources, such as: hardware failures, software bugs, malicious attacks, human operation / maintenance errors and natural disasters. The relevance of this topic is justified in view of the great importance that computer networks play for the functioning of companies' vital systems. The present work aims to provide analytical models, using the reliability block diagram modeling mechanism, to analyze the level of availability of computer networks considering the implementation of redundancy in critical components for the functioning of these networks. In addition, the sensitivity analysis index is used to determine which parameters, related to their components, have the greatest impact on their availability in order to direct strategies for increasing this metric. The infrastructure of the original computer network (base architecture) was analyzed and two additional architectures were proposed with an increase in the level of redundancy in order to analyze the impact of each of its parameters on the availability of the system. The repair time related to the link in the base architecture, the repair time related to the server in architecture 2 and the repair time related to the host in architecture 3 are the parameters that most impact on the availability of the entire system.