There's only one way to maximize the responsiveness and business value of all your products or enterprise systems: architect them. But implementing and managing software architecture across a value-chain, product-line, or enterprise can be tremendously difficult. Unless you understand that architecture will interact with your organization and unless you know what to do, even the most sensible architectures can quickly stagnate or lead to more unpleasant surprises.The authors, a team of leading architects, will show you exactly how to field resilient, long-lasting enterprise architectures. Software Architecture: Organizational Principles and Patterns introduces the breakthrough VRAPS (Vision, Rhythm, Anticipation, Partnering and Simplification) model for software architecture and demonstrates how to leverage it through real-world case studies and patterns.
DAVID M. DIKEL is a senior member of the professional staff at SRA International, where he focuses on large-scale architecture definition and management.
DAVID KANE is Director of the Technology Team at SRA International, where he specializes in Web-based applications and software architecture.
JAMES R. WILSON is Chief Technology Officer for Cyberserv, where he manages software product-line architecture and Web applications.
1. What You Can't See Could Help You.
What This Book is About. Software Architecture's Growing Importance. For Some, the News They are Stakeholders Comes Too Late. Principles Reveal the Hidden. Vision. Rhythm. Anticipation. Partnering. Simplification. Taking Action With Principles. Organizational Principles at Work: The Architect's New Job. Rhythm. Vision. Simplification and Anticipation. Partnering. Principles on the Web. Summary.2. The VRAPS Reference Model: How the Pieces Fit Together.
Overview. Why Models are Important. The VRAPS Model. Context. Organizational Principles for Software Architecture. The Role of Principles. Vision. Rhythm. Anticipation. Partnering. Simplification. Principles Interact. Conceptual Framework. Criteria. Patterns. Antipatterns. Applying the VRAPS Model. VRAPS Evolution. Summary.3. Projecting and Unifying Vision.
Overview. Vision Definition. Mapping Value to Architectural Constraints. Congruence and Flexibility. Vision Challenges. Limits of Architect Influence. Executive and Architect Cooperation. Product Lines Increase the Challenges to Architects and Executives. Recognizing Breakdown. Shaping a Vision. Will the Real Architect Please Stand Up? Vision and Leadership. No Respect. Putting Vision Into Practice: Criteria, Antipatterns, and Patterns. Criterion 1: The architect's vision aligns with what his or her sponsors, users, and end customers are trying to accomplish. Criterion 2: Practitioners trust and use the architecture. Criterion 3: Tacit knowledge about architecture and components is visible and accessible to users. Summary. Other Applicable Patterns and Antipatterns.4. Rhythm: Assuring Beat, Process, and Movement.
Overview. Tempo. Content. Quality. Rhythm Definition. Motivation. Rhythm Aids Transition Management. Rhythm Drives Closure. Putting Rhythm Into Practice: Criteria, Antipatterns, and Patterns. Criterion 1: Managers periodically reevaluate, synchronize, and adapt the architecture. Criterion 2: Architecture users have a high level of confidence in the timing and content of architecture releases. Criterion 3: Explicit activities are coordinated via rhythm. Summary. Other Applicable Patterns and Antipatterns.5. Anticipation: Predicting, Validating, and Adapting.
Overview. Prediction. Validation. Adaptation. Anticipation Definition. Anticipation in Action. Pulling Architectures in Many Directions. The Architecture Customers and Their Customers. Aiming Too Far Into the Future. Aiming Too Close to the Present. Balancing the Needs of Today and the Future. Striking a Balance. Putting Anticipation Into Practice: Criteria, Antipatterns, and Patterns. Criterion 1: Architecture capability is regularly enhanced to respond to anticipated risks and requirements of architecture customers and their customers, market-driving standards and evolving technology, and changes in strategic business directions. Criterion 2: Technical and business risks and opportunities are evaluated through a quick cycle of review and development. Criterion 3: Features, budgets, plans, or schedules are adapted when it is recognized that critical estimates or assumptions are incorrect. Summary. Other Applicable Patterns and Antipatterns.6. Partnering: Building Cooperative Organizations.
Overview. Cooperative Relationships. Partnering Definition. Architecture Stakeholders. Clear, Cooperative Roles. Maximizing Value. Industrial Roots. Contract Management. Networked Organizations. Value Chain. Trust. Putting Partnering Into Practice: Criteria, Antipatterns, and Patterns. Criterion 1: The architect continually seeks to understand who the most critical stakeholders are, how they contribute value, and what they want. Criterion 2: Clear, compelling agreements exist between stakeholders. Criterion 3: Both policies and informal rules of social conduct enforce cooperation. Summary. Other Applicable Patterns and Antipatterns.7. Simplification: Clarifying and Minimizing.
Overview. But What is Essential? Simplification DeTHnition. Conway's Law. Clarification. Minimization. Putting SimpliTHcation Into Practice: Criteria, Antipatterns, and Patterns. Criterion 1: Developers continue to use the architecture over time, reducing cost and complexity. Criterion 2: The architecture group clearly understands the essential minimal requirements and builds them into core elements. Criterion 3: Long-term budget and action ensure that elements are removed from the core when 1) they are not shared, or add unnecessary complexity, and 2) there is a clear business case. Summary. Other Applicable Patterns and Antipatterns.8. Principles at Work: The Allaire Case Study.
Introduction. Why Allaire? Five Organizational Principles. What was Our Approach? About the Results. Vision-Making a Good Vision Real. Definition and Description. Practices to Project Architecture Vision and Keep It Alive. Warning Signs Identified by Allaire Staff. Rhythm-The Beat Goes On. Definition and Description. Practices That Help an Architecture Organization Stay in Sync. Warning Signs Identified by Allaire Staff. Anticipation-Predict, Validate, and Adapt. Definition and Description. Practices to Maintain an Architecture's "Friction With the Future". Warning Signs Identified by Allaire Staff. Partnering-Lifelines. Definition and Description. Practices That Support Partnering. Warning Signs Identified by Allaire Staff. Simplification-Finding the Essential. Definition and Description. Practices That Support Simplification. Warning Signs Identified by Allaire Staff. Summary.9. Case Study: Building and Implementing a Benchmark Using VRAPS.
Overview. Benchmarking Provided a Framework. Survey Template. Organization Background and Context Template. Architecture Overview and Return on Investment Template. Principle Template. Practice Template. How We Conducted the Benchmark. Getting to a Workable Vision. Conducting the Interviews. Benchmark Results and Lessons Learned. Principles Resonated. Principle Relationships. Lessons Learned. Summary.A. Quick Reference Table: Principles, Criteria, Antipatterns, and Patterns. B. Antipattern and Pattern Summaries.