Virtual network interfaces are the attachment points where workloads connect to networks and where many policy decisions are enforced, making them central to CloudNetX design scenarios. This episode defines a vNIC as a logical interface that carries addressing, routing, and security policy context for a virtual machine or similar workload, and it explains why vNIC configuration affects segmentation, logging, and performance. The first paragraph focuses on how vNICs enable network separation by attaching different interfaces to different subnets or trust zones, allowing management traffic and data traffic to be isolated even when they share the same compute resource. It also explains how vNICs interact with stateful rules, identity mapping, and observability, because the interface context often determines what traffic is allowed and how activity is recorded.