What are the main differences between Zero Trust and traditional perimeter-based security models?

Zero trust security differs from traditional perimeter-based security models in several fundamental ways:

1. Assumption of Compromise: Zero trust operates on the assumption that no user or device, whether inside or outside the network perimeter, should be trusted by default. In contrast, traditional models often rely on the perimeter as a trusted boundary.

2. Verification and Authentication: Zero trust requires continuous authentication and verification of users, devices, and applications trying to connect to the network or access resources. This stands in contrast to traditional models where once inside the perimeter, access is often less rigorously monitored.

3. Micro-Segmentation: Zero trust implements micro-segmentation, which divides the network into smaller segments to limit the lateral movement of threats. Traditional security models typically have a more flat network structure, making it easier for attackers to move freely once inside the perimeter.

4. Least Privilege Access: Zero trust follows the principle of least privilege, where users and devices are only granted access to the resources they specifically need for their tasks, reducing the attack surface. Traditional models might have broader access permissions once inside the perimeter.

5. Continuous Monitoring: Zero trust emphasizes continuous monitoring of network traffic, user behavior, and device health to quickly detect and respond to potential threats. Traditional models may rely more on periodic security checks.

These factors represent key shifts in approach and philosophy that differentiate zero trust from traditional perimeter-based security models.