Availability modeling and analysis of a VoD service for eucalyptus platform

Cloud computing environments are an emerging technology that aims at proving several cloud services over the Internet, making it possible to provide a huge variety of applications with different purposes to users. Multimedia services are examples of these new services that use cloud computing, like video streaming, where the user can access their videos from cloud environments. For cloud service systems, assurance of high-availability of cloud services is a challenging and critical issue. In this paper, we evaluated the video streaming service´s availability for video on demand cloud system. Hierarchical modeling strategy, availability models combining reliability blocks diagrams (RBD) and continuous time Markov chain (CTMC) were used, indicating a system availability of 1.92 nines. The critical component of the system was indicated through sensibility analysis. We realized a model validation technique to demonstrate that the models represent the behavior of the real system.