In physical security, the employment of barriers with the capacity to delay the progress of an intruder is one of the security designs of the Defense-in-Depth (DiD) strategy. To validate the effectiveness of the design, which of the following should be conducted first?
A. Target hardening
B. Universal element conceptual mapping
C. Critical path analysis
D. Fire drill to protect life

Kindly be reminded that the suggested answer is for your reference only. It doesn’t matter whether you have the right or wrong answer. What really matters is your reasoning process and justifications.

My suggested answer is C. Critical path analysis.

Source: Wikipedia

Defense-in-Depth (DiD)

• Defense-in-Depth (DiD), also known as layered defense, features diversity and redundancy of implementation of security controls.
• It uses layers of barriers as security controls in physical security design to deter, detect, delay, and respond to intrusions.
• Crime prevention through environmental design (CPTED) complements Defense-in-Depth (DiD) when designing a security solution.

Critical Path Analysis

• The critical path method (CPM), or critical path analysis (CPA), is an algorithm for scheduling a set of project activities. It is commonly used in conjunction with the program evaluation and review technique (PERT).
• A critical path is determined by identifying the longest stretch of dependent activities and measuring the time required to complete them from start to finish.
• In project management, a critical path is the sequence of project network activities which add up to the longest overall duration, regardless if that longest duration has float or not. This determines the shortest time possible to complete the project.

Source: Wikipedia

Critical Path Analysis can be applied in various contexts, including physical security. The minimum time taken by an intruder to breach the security can be assessed through identifying the critical path of security controls or barriers. Once the detection system detects an instruction, the response time must be less than the minimum time to breach the security.

Universal element conceptual mapping

• The concept of universal element is that of a continuum of items or actions on a single dimension that will give a family of elements within a DiD strategy.
• A conceptual map identifies risk curves for delay probability and detection probability.

Source: Security Science: The Theory and Practice of Security

Target Hardening

Target hardening is aimed at denying or limiting access to a potential crime target through the application of artificial or physical barriers. Target hardening can
take a variety of forms that range from strengths of materials (i.e., make the barrier more resistant to penetration) to covert surveillance of perimeters, open ground, and facilities.

Source: Security Science: The Theory and Practice of Security

Fire Drill

To protect life is the golden rule and a paramount control objective of all the security controls. Fire drill protects human life (so do other controls), but it itsn’t related to the instruction. In other words, Fire drill can not validate the effectiveness of the employment of barriers with the capacity to delay the progress of an intruder is one of the security designs of the Defense-in-Depth (DiD) strategy..

References

• The ABCs of the Critical Path Method
• The Conceptual and Scientific Demarcation of Security in Contrast to Safety
• Security Science
• Critical path method
• Identifying and Measuring Security Critical Path for Uncovering Circuit Vulnerabilities
• Pandemic Influenza Preparedness (‎PIP)‎ framework: critical path analysis: from detection to protection
• Restarting Your Pandemic-Delayed Project With the Critical Path in Mind