Nutanix Flow protects your applications at the network layer using a software firewall at the hypervisor level. The generalized term is "microsegmentation" and it basically allows you to run a firewall on every single virtual machine's network adapter.
Because this is all software, and native to Nutanix AHV, you can define / update / migrate rules live and at anytime in your environment. It scales with your environment, runs on every node, and can even span clusters and datacenters! In this video we run through the steps to create a security policy to protect an application in your environment.