Jude, a security professional in an eccouncil video

Full Certification Question

Jude, a security professional in an organization, was instructed to strengthen the security of the organization. In the process, to prevent direct attacks against an information system, Jude implemented a strategy based on the military principle that it is more difficult for an enemy to defeat a complex and multi-layered security system. What is the security strategy that Jude has implemented to prevent direct attacks against the information system?