This chapter covered systems engineering concepts and various phases in the process. Software development is in the development phase of a systems engineering process. Software development follows life cycle models. When a development model follows simple and sequential methods, then it is called a simplistic model, and where iterations are allowed throughout the cycle, then such a model is called a complex model. Security in the development, test, and operational implementations is critical to overall software security. Some of the important security controls in development include change control procedures and technical review for security.

In the next chapter, we will cover assurance requirements in the software and related security testing procedures.