author : Frank Buschmann

Security can be an intimidating subject area, but this need not be the case. Although time constraints may prevent systems engineers from becoming security specialists, guarding systems against attack is essential. With the growing success of the Internet, computer and software systems have become more and more networked. Writing from the heart of the patterns community, the authors address key questions and present corresponding proven solutions, clearly showing you how to build secure systems.

In a time where systems are constantly at risk, it is essential that you arm yourself with the knowledge of different security measures. This pioneering title breaks down security at various levels of the system: the enterprise, architectural and operational layers. It acts as an extension to the larger enterprise contexts and shows you how to integrate security in the broader engineering process.

Essential security topics include:
• Enterprise level security – security management, principles, institutional policies (such as need-to-know) and enterprise needs (including confidentiality, integrity, availability, accountability, I&A, access control and audit).
• Architectural level security – system level solutions responding to enterprise level policies – and the most important level for facilitating building security into a system.
• User level security – concerned with achieving security in operational contexts.

Pattern-oriented software architecture is a new approach to software development. This book represents the progression and evolution of the pattern approach into a system of patterns capable of describing and documenting large-scale applications.

A pattern system provides, on one level, a pool of proven solutions to many recurring design problems. On another it shows how to combine individual patterns into heterogeneous structures and as such it can be used to facilitate a constructive development of software systems.

Uniquely, the patterns that are presented in this book span several levels of abstraction, from high-level architectural frameworks and medium-level design patterns to low-level idioms.

The intention of, and motivation for, this book is to support both novices and experts in software development. Novices will gain from the experience inherent in pattern descriptions and experts will hopefully make use of, add to, extend and modify patterns to tailor them to their own needs. None of the pattern descriptions are cast in stone and, just as they are borne from experience, it is expected that further use will feed in and refine individual patterns and produce an evolving system of patterns.

Software patterns have significantly changed the way we design, implement, and think about computing systems. Patterns provide us with a vocabulary to express architectural visions and approaches to development, as well as examples of representative designs and detailed implementations that are clear and to the point.

Until now there has been no complete and up-to-date work on the pattern concept available. The knowledge of the latest advances in the conceptual foundations of patterns remains locked in the minds of a few experts and thought leaders in the patterns community. Pattern-Oriented Software Architecture, Volume 5 (POSA 5) mines this knowledge and documents it for the consumption of the broader software development community.

POSA 5 presents, discusses, relates, and contrasts the many known flavors and applications of the pattern concept: stand-alone patterns, pattern complements, pattern compounds, pattern stories and sequences, and pattern languages. For each concept flavor, the authors investigate its fundamental and advanced properties, and explore insights that help readers master concepts that are well known in the pattern community.

The book is presented in three main parts:

• Part I, Inside Patterns, reflects on the use of stand-alone patterns gained over the past decade
• Part II, Between Patterns, moves outside of the individual pattern to explore the relationships between patterns
• Part III, Into Pattern Languages, builds on the concepts and conclusions of the first two parts by introducing pattern languages

The authors provide an overview of the current state of knowledge and practice in software patterns. The book codifies the key roles and relationships of the pattern concept in one volume, allowing readers to deepen their understanding of what patterns are, what they are not, and how to use them successfully.

This concepts volume revisits principles developed in previous POSA volumes and other sources of software pattern literature to enhance, revise, and extend these ideas.