On terms of the underlying concept of lifecycle methodologies, the ‘V Model’ SDLC appears as one Agile variation to encapsulate any approach within a simplified lifecycle framework. Ultimately, the choice depends on requirements and resources with ‘the best choice’ often subjective to define.
Documentation is initiated at code committal, occurring at the end of the Execution phase. OSSD offers an ‘onion’ datagram depicting a recommendable hierarchy for development communication.
Internet-Speed Development is an approach that uses multiple teams in different time-zones, to enable 24-7 activity on the project. In ISD, suited for larger closed-source projects, techniques from multiple methodologies can be used but definition must be done in the Initiation phase and funding, infrastructure and skills must be plentiful.
CSE (Cleanroom engineering) is a methodology that focuses on defect prevention by using automatic verification capabilities, model checking, ‘Petri nets’ (that use formulas attributed to objects in visualisation software) and methods such as BSM (Box Structure) along with human review.
Box Structure Methodology applies to the creation of state data by taking conceptualisation of requirement functions into a state of relation organising as ‘building blocks’ and then transitioning to full programmable models with all procedures of the required system mapped or logically supported.
SDLCs are often considered as tools, mostly modifiable and generally of high resemblance despite detailed definition and conventions. The choice of which to employ is dependent on the project and the parties’ capabilities, requirements and attitudes.
In a circa-millennium study, Wang showed higher difficulty in adoption of OOA but gains in analysis and design over data-flow modelling and other traditional methods. Due to its higher reliability of design, albeit exhaustive, OOA is recommended for projects with focus on component reuse and scalability.