CSSLP Domain 1:4 Software Development Methodologies
Software Development Methodologies - Introduction

This course is the fourth installment of four courses covering Domain 1 of the CSSLP, covering the topic of software development methodologies.

Learning Objectives

  • Learn about the secure development lifecycle and the implications it has on your software
  • Understand the various software development methods for keeping your environments secure
  • Learn about the software development lifecycle

Intended Audience

This course is designed for those looking to take the Certified Secure Software Lifecycle Professional (CSSLP)​ certification, or for anyone interested in the topics it covers.


Any experience relating to information security would be advantageous, but not essential. All topics discussed are thoroughly explained and presented in a way allowing the information to be absorbed by everyone, regardless of experience within the security field.


If you have thoughts or suggestions for this course, please contact Cloud Academy at



The concluding module in Domain 1 one of Secure Software Concepts is our Software Development Methodologies in Section 4. The secure development life cycle is the result of combining security with the classic SDLC model. Now, the idea of including security as part of the normal customary development process is what you might call the "Holy Grail" and has been for decades.

The skill of designing and building software and understanding how security works being integrated into it are things that at many days were known for being at loggerheads with each other. But, in recent years, it has become more and more obvious that integrating security into software development so that it becomes secure by design from the very beginning is becoming not just a nice to have, but an absolute necessity.

Now most development methodologies have had to adapt to include security from project onset, and then carry it through at every single phase so that we get the security holy grail features secure by design and secure by default. Now the relationship of information assurance to the software lifecycle is to make sure that it goes with every single phase of the project development. It has to start at the beginning to be designed in. It has to carry through through all phases, survive all change management approaches. It needs to be carefully considered when weighing functionality, usability, utility, and other features that have to do with how well it's going to do its job along with user acceptance, to make sure that there is a balance attained between these various and competing objectives. And it needs to carry through into operation. And, as other things within the software are mended or patched or added, security needs the same attention.

This is all part of the operational risk assessment that we have to do from the very beginning with increasing refinement as we get closer and closer to delivery and then into operation. And then it becomes a part of our normal operating infrastructure and maintained with all of the same diligence.

About the Author
Learning Paths

Mr. Leo has been in Information System for 38 years, and an Information Security professional for over 36 years.  He has worked internationally as a Systems Analyst/Engineer, and as a Security and Privacy Consultant.  His past employers include IBM, St. Luke’s Episcopal Hospital, Computer Sciences Corporation, and Rockwell International.  A NASA contractor for 22 years, from 1998 to 2002 he was Director of Security Engineering and Chief Security Architect for Mission Control at the Johnson Space Center.  From 2002 to 2006 Mr. Leo was the Director of Information Systems, and Chief Information Security Officer for the Managed Care Division of the University of Texas Medical Branch in Galveston, Texas.


Upon attaining his CISSP license in 1997, Mr. Leo joined ISC2 (a professional role) as Chairman of the Curriculum Development Committee, and served in this role until 2004.   During this time, he formulated and directed the effort that produced what became and remains the standard curriculum used to train CISSP candidates worldwide.  He has maintained his professional standards as a professional educator and has since trained and certified nearly 8500 CISSP candidates since 1998, and nearly 2500 in HIPAA compliance certification since 2004.  Mr. leo is an ISC2 Certified Instructor.