What does segmentation involve in network security?

Segmentation in network security refers to the practice of partitioning a network into smaller, distinct segments, each with its own security controls and access permissions tailored to the specific needs of that segment. This approach enhances security by reducing the attack surface; if one segment is compromised, the attacker has limited access to the rest of the network. It allows organizations to apply different security measures according to the sensitivity of the data being processed or stored in each segment.

This method is particularly vital in contexts such as PCI DSS compliance, where sensitive payment card data requires stringent security measures. By segmenting networks, security teams can enforce stricter controls on environments that handle sensitive data, while allowing less sensitive systems to operate with more flexibility. This not only enhances security posture but also aids compliance efforts by clearly delineating areas of risk.

Adding redundancy to systems or increasing bandwidth may improve performance and availability, but they do not directly contribute to the security-focused objectives of segmentation. Similarly, creating a single unified network may simplify management but can lead to greater vulnerabilities, as it lacks the protective barriers that segmentation provides.