ASE: A comprehensive pattern-driven security methodology for distributed systems

Incorporating security features is one of the most important and challenging tasks in designing distributed systems. Over the last decade, researchers and practitioners have come to recognize that the incorporation of security features should proceed by means of a systematic approach, combining principles from both software and security engineering. Such systematic approaches, particularly those implying some sort of process aligned with the development life-cycle, are termed security methodologies. One of the most important classes of such methodologies is based on the use of security patterns. While the literature presents a number of pattern-driven security methodologies, none of them are designed specifically for general distributed systems. Going further, there are also currently no methodologies with mixed specific applicability, e.g. for both general and peer-to-peer distributed systems. In this paper we aim to fill these gaps by presenting a comprehensive pattern-driven security methodology specifically designed for general distributed systems, which is also capable of taking into account the specifics of peer-to-peer systems. Our methodology takes the principle of encapsulation several steps further, by employing patterns not only for the incorporation of security features (via security solution frames), but also for the modeling of threats, and even as part of its process. We illustrate and evaluate the presented methodology via a realistic example -- the development of a distributed system for file sharing and collaborative editing. In both the presentation of the methodology and example our focus is on the early life-cycle phases (analysis and design).