Why IP-based CAR Is Invalid on a WAN-side Interface?
Because NAT is configured on the WAN-side interface, the device cannot differentiate private IP addresses.
In V200R002C00 and later versions, to configure IP-based CAR on a WAN-side interface, create a VLANIF interface and configure IP-based CAR on the VLANIF interface.
To limit the download rate, configure IP-based CAR for a specified destination address in the outbound direction.
To limit the upload rate, configure IP-based CAR for a specified source address in the inbound direction.