What is the primary purpose of tier to tier segmentation?

The primary purpose of tier to tier segmentation is to segment application traffic based on direction without needing to know the exact ports yet. This approach allows for the establishment of policies that control how traffic flows between different tiers of an application, such as from a web tier to an application tier or from an application tier to a database tier. By focusing on the direction of the communication rather than specific ports, organizations can implement security controls more quickly and flexibly, adapting to changes in the applications and their environments without being overly reliant on detailed network configurations.

This method of segmentation is crucial for zero trust security models where restrictions on communication must be enforced based on the context and purpose of the traffic, rather than simply the ports and protocols in use. It enables security teams to effectively manage and protect sensitive data flows while minimizing the attack surface.