+Direct L2 Loopback (Switch or wire loopback)
+--------------------------------------------
+NFVbench supports benchmarking of pure L2 loopbacks (see "--l2-loopback vlan" option)
+
+- Switch level loopback
+- Port to port wire loopback
+
+In this mode, NFVbench will take a vlan ID and send packets from each port to the other port
+(dest MAC set to the other port MAC) using the same VLAN ID on both ports.
+This can be useful for example to verify that the connectivity to the switch is working properly.