Answers and explanations

  1. Layer 2 of the OSI Reference Model is the lowest layer. The data-link layer is the lowest layer that a switch operates at.
  2. A router works at Layer 3 of the OSI Reference Model as it works on IP addresses.
  3. A VLAN is created on a switch that works at layer 2 of the OSI Reference Model.
  4. A Web Application Firewall works at Layer 7 of the OSI Reference Model.
  5. The web application firewall is normally installed on a web server as its job is to protect web applications from attack.
  6. The default setting for a firewall is block all, allow by exception.
  7. Implicit deny is used by both the firewall and the router where the last rule is deny all. Should there not be an allow rule, then the last rule applies and it is known as implicit ...

Get CompTIA Security+ Certification Guide now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.