Rationale Support for Maintenance of Large Scale Systems

Software maintenance has long been one of the most difficult and expensive phases of the software life-cycle. Maintenance is especially difficult for large-scale systems. The more code involved, the larger the chance that there may be unexpected interactions that may cause problems when updates and corrections are made during maintenance. The large number of developers who were probably involved at various points in the system’s creation means that it is likely to be difficult to answer questions about the intent behind the design and implementation decisions. The designer’s, or developer’s, intent can be captured as their Design Rationale. Unlike standard design documentation, which is a description of the final design, Design Rationale (DR) offers more: not only the decisions, but also the reasons behind each decision, including its justification, other alternatives considered, and argumentation leading to the decision.