3.5. Network Interface Controller
The network interface controller (NIC) is a network adapter or LAN adapter that connects a computer to a computer network. The NIC operates on both the physical and data link layers of the machine and enables network connectivity. All virtualization hosts in a Red Hat Virtualization environment have at least one NIC, though it is more common for a host to have two or more NICs.
One physical NIC can have multiple virtual NICs (vNICs) logically connected to it. A virtual NIC acts as a network interface for a virtual machine. To distinguish between a vNIC and the NIC that supports it, the Red Hat Virtualization Manager assigns each vNIC a unique MAC address.