Issues in on-line performability modeling and evaluation through the model-based approach

Performability is widely recognized to be a highly representative metric of the dependability and Quality of Service of a system. The today complex networked systems show complex interdependencies with profound impact on the quality of services provided. In addition, adaptivity of the system architecture and configuration with respect to unforeseen changes that can occur at run-time becomes one of the most challenging aspects. This document describes the experience made by the authors on the dynamic management of performability driven reconfigurations, illustrates the authors vision of open problems and next challenges, and finally mentions the future work we will be doing in such context.