Categorizing requirements for a contract-based system integration project

Categorizing requirements based upon their aspects and stakeholder intent can help requirements engineers and other developers to group and retrieve the requirements for analyzing the aspects of concern. The analysis is essential for project planning, system verification and validation, and integration coordination. For software requirements, researchers and practitioners have identified a set of categories, such as functional, performance, safety, to categorize a requirement. In a large systems engineering and integration project comprised of not only software but also hardware and activities in other disciplines (e.g., electrical, civil engineering), we encountered many additional, different aspects of the system that need to be analyzed and thus the requirements need to be categorized for those aspects. This experience report describes the lessons learnt in categorizing requirements in this project. The report provides insights for the practical issues of the categorization and our research on how more effectively the categorization could be done.