Asus RT-AC68W AiMesh Setup guide in English - Page 13

Ethernet backhaul Wired connection between AiMesh router and node AiMesh system supports both wireless and wired connection between AiMesh router and node to maximize throughput and stability. AiMesh analyzes the wireless signal strength for each frequency band available, and then determines automatically whether a wireless or wired connection is best to serve as the inter-router connection backbone. Follow the setup steps to establish a connection between the AiMesh router and node via Wi-Fi first. After that: 1. Place the node in the ideal locations for best coverage. Run Ethernet cables from the LAN port of the AiMesh router to the WAN port of AiMesh node. AiMesh system will auto-select the best path for data transmission, whether wired or wireless. Modem AiMesh router AiMesh node 2. If you want to keep wired connection manually between AiMesh router and node, launch web GUI http://router.asus.com, and go to Network Map. Click on AiMesh icon, you will find the node list at the right side. And then click on the node picture  More Config  Connection Priority  Ethernet.