User-friendly dependability evaluation tool

In order to permit users with little analytic background to evaluate dependability, modeling tools require a user-friendly front end. With this motivation, we have developed a software tool referred to as SDDS for 'Software Dependability for Distributed Systems.' In particular, we have designed and implemented a graphical user interface (GUI) based on a 'user-language' - basic building blocks representing system components and/or subsystems. Therefore, the user can specify his/her dependability model at a high level. SDDS then translates the high-level specification into a representation that can be automatically solved by the underlying modeling engines SHARPE or SPNP (both from Trivedi, a Professor at Duke University). The translation and solution processes are transparent to the user. We first illustrate the design of SDDS. We then describe, from a software engineering perspective, how SDDS can be utilized effectively for evaluation and improvement of system design.