Evaluating software architecture solutions in the cloud era

The quality of software architecture solutions is difficult to evaluate, making selection between architecture alternatives cumbersome. The cloud offerings add alternatives, by increasing complexity and dynamic flexibility of underlying deployment considerations. This research aims to identify the architects' main quality concerns regarding the system in three different environments: physical (static) deployment, virtual (private) cloud and public cloud. In this position paper, we present our evaluation of the importance architects attribute to applications characteristics (Functionality, Availability, Usability) and infrastructure and platform characteristics (Efficiency, Serviceability, Portability) in each of the above deployment environments. A survey, in which 34 experienced software architects participated, reveals the differences between quality concerns of architects and end-users, and between the different environments and system layers. Architects consider Portability (dynamic nature of applications and systems) as more important in private and public clouds than in static environments, while in the other quality attributes no significant difference was observed. In addition, architects perceive that end-users do not distinguish between cloud and non-cloud environments, and significantly consider that applications characteristics are more important than infrastructure ones.