2. Towards a Conceptual Framework for Security Patterns

We introduce security patterns as the most mature domain within cyberpatterns, and outline a conceptual framework to help understand and develop good security patterns. Security patterns help us move from an improvised craft to engineering discipline because they transfer knowledge about proven solutions in an understandable and reusable format to experienced users and novices alike. Although security patterns are widely known, many questions remain unanswered regarding their conceptual foundation and practical use. We characterise the current pattern schemes using the Zachman Framework for enterprise architecture modelling, which allows us to structure and pose questions about both the problem domain and corresponding solutions provided by security patterns. We propose a parallel security plane overlaying the entire Zachman grid allowing the separate consideration of security within the security plane using the interrogative questions (who, what, where, when, why and how) to evaluate the six aspects. The integration between security and functional concerns is similarly aided by using the correspondence between aspects in the security and functional planes to decompose and examine the relationship between security patterns and problem context. We also briefly discuss security patterns as transformations, and related concepts such as tactics that may usefully be applied to security. We conclude with a set of unsolved challenges for security patterns. This discussion is relevant to other types of cyberpattern such as attack patterns, and may aid the eventual development of a comprehensive framework for cyberpatterns.