Virtual Network Interface

Virtual network interfaces are linked to a hardware device, but are not hardware devices.

A virtual network interface is generally associated with a physical network, another virtual interface, a loopback interface or other standalone interfaces.

Types of Virtual Network Interfaces

Type	Example	Description
Aliases	eth4:5, eth4:6	Used to handle multiple IP-addresses per interface. Supported for backwards compatibility.
Bridges	br0, br-lan	Used to make multiple network interfaces behave as one network interface.
Stacked VLANs	10, 20	IEEE 802.1ad type network, using two or more tags in each packet.
Special purpose	imq0, teql3	Used to change the order of outgoing or incoming network packets.
Tunnel interfaces	pppoe-dsl, tun0, vpn1	Used to send packets over a tunneling protocol.
VLANs	eth4.0, vlan0	Used to separate a network into multiple virtual networks.
Wireless operating mode virtual interfaces	wlan0, ath3	A wireless subsystem created automatically for a wireless NIC master interface.