Ethernet Control Model (CDC ECM)

configname: CONFIG_USB_CONFIGFS_ECM

USB Gadget Drivers
└─>Ethernet Control Model (CDC ECM)
In linux kernel since version 3.11 (release Date: 2013-09-02)  
The "Communication Device Class" (CDC) Ethernet Control Model.
That protocol is often avoided with pure Ethernet adapters, in
favor of simpler vendor-specific hardware, but is widely
supported by firmware for smart network devices.