Network Infrastructure

Backbone of modern organizations
Comprises hardware, software, services, and facilities for network support and management

Security measures to protect sensitive information
Often referred to as "Air Gapping”
Isolates a system by physically disconnecting it from all networks
- Isolated from both local and internet networks
- Disconnection from direct or indirect connections
Example:
- ICS system
  - Systems on power plants or water treatment facilities are often air gapped to prevent cyber attacks that could lead to real-world damage.
However, Air Gap systems are not infallible
Physical separation is one of the most secure methods of security, but it is still vulnerable to sophisticated attacks
- Example:
  - Stuxnet

Establishes boundaries within a network to restrict access to certain areas
Implemented using firewalls, VLANs, and Network Devices that can control traffic based on rules and policies
Example:
- Use of VLANs in corporate network
  - VLANS can segregate network traffic, ensuring that data form one department cannot be accessed by another department
  - Reduces congestion, manages network traffic and improves security
- Use of firewalls to create a screened subnet network
  - Logical subnetwork that contains the organization's external-facing services separating them from the internal network
Logical separation should be properly configured to be more effective in network security
- Technically not as secure as Physical Separation
- Network devices can be exploited

Physical Separation (Air-Gapping)
- High security, complete isolation
Logical Separation
- More flexible, easier to implement
- Less secure if not configured properly