Network segmentation refers to the act of dividing different parts of a network into separate segments or subnets. This is done either physically or technologically, usually as part of a network access control system that limits who can access what parts of the network.
Once organizations have identified subnetworks, they establish virtual fences around them using a variety of techniques, including VLANs, SDNs, and firewalls.
A cybersecurity posture is essentially the total procedures, policies, and services that an organization uses to defend itself from cyber attack. Companies evaluate their security risk then develop policies, employee training procedures, and, if they have the resources, malware, virus, and other threat detection services, focusing on their most vulnerable assets.
In short, a cybersecurity posture describes an organization’s cyber threat readiness and identifies areas where this readiness can be improved.