4.4.4 Application of the ‘Vee’ to Incremental and Evolutionary Development

The technical aspects of the project cycle have been modeled as a sequence of events descending with increasing detail through decomposition and definition, from user requirements to piece parts and lines of code. Then starting at the lowest level, the technical aspects ascend through integration and verification up to the system at the highest level. This representation as a ‘Vee’ was first presented in the 1991 NCOSE symposium in Chattanooga, Tennessee (Ref. 1). The cycle presented in that paper was described as a single thread, or what is now called in the software world the grand design. Extension of this concept to incremental and evolutionary environments is essential to provide for application on any project. This paper provides that model and visualization. Three cases are examined: an incremental development with a single product delivery, incremental development with incremental product delivery, and evolutionary product development.