🔒

Network Segmentation in IT Security

Jun 16, 2025

Overview

This lecture discusses the importance of network segmentation in IT security, highlighting its applications for performance, compliance, and securing both consumer and industrial devices.

Segmentation in IT Security

  • Segmentation involves separating devices physically or virtually to control communication and enhance security.
  • Networks can be segmented using VLANs (Virtual Local Area Networks).
  • Segmentation improves performance by isolating high-data-transfer applications onto their own networks.
  • Security segmentation limits which devices can communicate, reducing attack surfaces.

Compliance and Industry Requirements

  • Some standards, like PCI DSS for payment card industry, require network segmentation when storing sensitive data.
  • Segmentation may be a design requirement for regulatory compliance.

IoT and IIoT Device Segmentation

  • IoT (Internet of Things) devices include sensors, smart home devices, and wearables, often with weak security features.
  • IIoT (Industrial Internet of Things) devices enable machine-to-machine communication in manufacturing, medical, or utility environments.
  • Segmenting IoT/IIoT devices prevents them from accessing sensitive data and protects critical operations.

SCADA, ICS, and OT Network Segmentation

  • SCADA (Supervisory Control and Data Acquisition) and ICS (Industrial Control Systems) require strong segmentation due to critical real-time monitoring needs.
  • OT (Operational Technology) systems, such as those managing power grids or traffic, depend on maximum uptime and security via segmentation.
  • Segmented networks protect against failures that could affect infrastructure or public safety.

Segmentation for Guests and BYOD

  • Guest networks allow internet access without access to internal systems, improving security in homes and offices.
  • BYOD (Bring Your Own Device) policies segment personal devices to keep personal and company data separate and secure.

Key Terms & Definitions

  • Segmentation — separating networks or devices to control traffic flow and access.
  • VLAN (Virtual Local Area Network) — a logical subnetwork used for segmenting traffic.
  • IoT (Internet of Things) — networked devices like sensors and smart devices.
  • IIoT (Industrial Internet of Things) — industrial machines networked for automation.
  • SCADA — systems for real-time data acquisition and control in industries.
  • ICS (Industrial Control System) — integrates with SCADA for managing industrial processes.
  • OT (Operational Technology) — hardware and software that controls physical devices.
  • BYOD (Bring Your Own Device) — policy allowing personal devices for work use.

Action Items / Next Steps

  • Review organizational requirements for compliance-related segmentation.
  • Assess current network for IoT/IIoT devices and apply segmentation as needed.
  • Set up or update guest networks to ensure proper isolation from internal systems.