A Reference Architecture is a generic architecture for systems that have similar characteristics. Also, reference architectures are defined based on past experience, and specific best practices therein. The focus of such a best-practices-based architecture is not so much on the essential requirements of a specific enterprise or a specific situation, but rather on general engineering qualities and how they can be met. As such, a reference architecture is a generalized architecture that can be applied to multiple solutions and across multiple enterprises. The informative role is dominant in this form of architecture, due to its natural focus on codifying reusable architectural knowledge.