Cisco Cyber Security Practice Exam

What can block electromagnetic fields around sensitive equipment?

1. Plastic enclosures

2. A Faraday Cage

3. Wooden barriers

4. Metallic mesh

The correct answer is: A Faraday Cage

The Faraday Cage is a structure that effectively blocks electromagnetic fields from penetrating its interior. This is achieved through its conductive material which redistributes electromagnetic energy around its surface, thereby preventing electric fields from appearing inside the cage. This principle is grounded in electromagnetic shielding, where the cage acts as a barrier against external electromagnetic interference (EMI) and protects sensitive electronic equipment inside from potentially damaging fluctuations. While plastic enclosures, wooden barriers, and metallic mesh can serve various protective functions, they do not provide the same level of interference protection as a Faraday Cage. Plastic and wooden materials are generally non-conductive and will not impede electromagnetic fields effectively. Although metallic mesh can provide some degree of shielding, it would not be as comprehensive as a solid Faraday Cage, which creates a complete barrier to electromagnetic fields regardless of their frequency.