@Solla-topee It is a Technicolor TC7200 cablemodem/router from my ISP. All the IP-addresses starting with 72:DA:xx:xx:xx:xx are the static ip addresses I mean.

Hello, I see in my router that the RE450 range extender is setting up multiple static ip addresses with the same MAC address. I know it is normal behavior for a range extender to set up a clone MAC...