NDI® (Network Device Interface) is a free protocol for Video over IP, developed by NewTek. It is designed to allow distribution of live professional video over existing IP infrastructure, freeing users from hardware constraints and gives the benefits of reduced cost and deployment time. NDI® (Network Device Interface) is a free protocol for Video over IP, developed by NewTek. It is designed to allow distribution of live professional video over existing IP infrastructure, freeing users from hardware constraints and gives the benefits of reduced cost and deployment time. NDI® (Network Device Interface) is a free protocol for Video over IP, developed by NewTek. It is designed to allow distribution of live professional video over existing IP infrastructure, freeing users from hardware constraints and gives the benefits of reduced cost and deployment time.