The best way to ensure that secure design principles are implemented in the new methodology of Agile development is to capture the information security requirements in mandatory user stories. Agile development is a software development methodology that follows an iterative, incremental, and collaborative approach, where the software is developed and delivered in small and frequent cycles, called sprints. Agile development emphasizes the values of customer satisfaction, working software, adaptive planning, continuous improvement, and cross-functional teamwork. Agile development uses user stories to define the features or functionalities of the software from the perspective of the end user. User stories are short and simple descriptions of what the user wants or needs from the software, written in the format of "As a [role], I want [feature], so that [benefit]." User stories also include the acceptance criteria, which are the conditions or tests that must be met for the user story to be completed or satisfied. To ensure that secure design principles are implemented in Agile development, the information security requirements should be captured in mandatory user stories, which means that the user stories must include the security features or functionalities that are essential for the software to be secure, such as authentication, authorization, encryption, or logging. The information security requirements should also be prioritized and aligned with the business goals and risks, and should be verified and validated at each sprint. By capturing the information security requirements in mandatory user stories, the security can be integrated and embedded in the software development process, rather than added or patched as an afterthought. References: CISSP All-in-One Exam Guide, Chapter 8: Software Development Security, Section: Software Development Methodologies, pp. 1004-1005.
