Software Engineering/Development Approaches

Also referred to as software development paradigms, these are process models for how the various tasks related to software development can be organized. Typical approaches or paradigms encountered in DoD software development include waterfall, incremental, and spiral as described below. The incremental development approach typically forms the basis for software development within the larger systems-level of evolutionary acquisition (EA).

Waterfall Approach: Development activities are performed in order, with possibly minor overlap, but with little or no iteration between activities. User needs are determined, requirements are defined, and the full system is designed, built, and tested for ultimate delivery at one point in time. A document-driven approach best suited for highly precedented systems with stable requirements.

Incremental Approach: Determines user needs and defines the overall architecture, but then delivers the system in a series of increments (“software builds”). The first build incorporates a part of the total planned capabilities; the next build adds more capabilities, and so on, until the entire system is complete.

Spiral Approach: A risk-driven controlled prototyping approach that develops prototypes early in the development process to specifically address risk areas followed by assessment of prototyping results and further determination of risk areas to prototype. Areas that are prototyped frequently include user requirements and algorithm performance. Prototyping continues until high risk areas are resolved and mitigated to an acceptable level.