Hello,
Thank you for your input.
The marking of the ports as eth0 and eth1 within the context of RutOS and OpenWRT is in general used separate LAN and WAN interfaces. This logic applies for devices, which have more than a single physical LAN port. All of them would still fall under the same eth0 interface, even VLANs are derived from eth0.x. Marking ports as 1, 2 or LAN1, WAN is for accessibility purposes and it is a rather more human-readable notation, than starting marking ports from 0.
Besides, the ports can be configurable as WAN and LAN, thus matching port names to their logical counterparts would not be quite correct.
Best regards,