Building Secure Applications using Pattern-Based Design Fragments

Developing and operating a complex secure application with high assurance is difficult and requires experts. Security patterns and best practices have been proposed to assist architects in designing secure applications. However, these are usually written independently of the underlying platforms and operating environment. This leads to a gap between patterns and the platforms, and does not directly support the design-level analysis and verification of systems to be built on those platforms. We propose an approach to incrementally build an application design using design fragments, which are specializations of patterns for target platforms. Design fragments can be composed and reused during design, and directly support design-level security analyses and operation level concerns. We apply this approach in a case study of the design and analysis of a smart electricity meter. We show how the approach can be used to iteratively address threats.