- Iterative Development
- Risk-Driven and Client-Driven Iterative Planning
- Timeboxed Iterative Development
- During the Iteration, No Changes from External Stakeholders
- Evolutionary and Adaptive Development
- Evolutionary Requirements Analysis
- Early "Top Ten" High-Level Requirements and Skillful Analysis
- Evolutionary and Adaptive Planning
- Incremental Delivery
- Evolutionary Delivery
- The Most Common Mistake?
- Specific Iterative & Evolutionary Methods
- What's Next?
- Recommended Readings
Specific Iterative & Evolutionary Methods
Specific agile methods are summarized in the next chapter. This section mentions some iterative methods (Evo and UP) that predate most agile methods; they may or may not be considered agile.
Of all the methods mentioned in this book (Scrum, XP, Evo, UP, OPEN, DSDM, ...) the UP or its variation the Rational Unified Process (RUP) is perhaps the most widely used. It is found in thousands or tens of thousands of development organizations worldwide. This does not mean it is well applied or well understood.
Evo
Evo was perhaps the first iterative and evolutionary method, starting in the 1960s. Evo recommends short 12 week iterations, and uniquely, evolutionary delivery each iteration. Evo adaptively plans iterations by highest value-to-cost ratio, and strongly promotes the unambiguous definition of quality requirements (such as load) with quantified and measurable statements.
Unified Process
The UP or RUP, first developed in the mid-1990s, brings together the knowledge of many experienced large-system architects and process-leaders at Rational Corp., and their customers, into a well-defined IID method. One key UP theme is risk-driven development in the early iterations, focusing on creation of the core architecture and driving down the high risks. The UP also includes the definition of common project workproducts, such as the Vision, Software Architecture Document, and Risk List.
Other Methods
In addition to UP and Evo, other IID methods include:
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The Microsoft Solutions Framework process, available from Microsoft Education. It is a description of best practices used by Microsoft.
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The OPEN process from Henderson-Sellers, Firesmith, and Graham [FH01].
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WinWin Spiral Model and MBASE Spiral Model from Barry Boehm (creator in the 1980s of the well-known iterative Spiral Model) and colleagues [BEKPSM98], [BP01].