Hi, Bruno, and congratulations on your BomeBox purchase!
Yes, this is APIPA mode and will work, however you will not be able to also talk to other devices on your home network since as you said it is in the 192.168.1.x range.
I suggest that you set up BomeBox WiFi as a DHCP client. You would set up the desired SSID and password (of your existing home network). Your existing ethernet master will then assign the BomeBox an address in your existing network range.
I believe you can change the default ethernet master address under advanced configuration settings. I don’t have my BomeBox handy right now but I will look up where this is changed and get back to you. Note that you cannot have 2 ethernet masters running on the same network so while you are connected to your BomeBox with your Mac in this fashion, you will not be able to access your home network. If you only want to connect to BomeBox or the WiFi network at a given time, I would recommend you just leave it in APIPA mode. I suppose there might also be a setting on your Mac to bridge your ethernet and WiFi connections but that is beyond the scope of our discussion. Your Mac would essentially be on 2 separate networks simultaneosly.
If your WiFi router has an ethernet port, and a cable that can reach, you could also just hook up your BomeBox ethernet to your router and since you router is an ethernet master, and the default for ethernet on BomeBox is a client, both your BomeBox and your computer could connect over your existing network. In this configuration, both BomeBox and your Mac would be assigned an address by your home router. Your BomeBox via ethernet and your Mac via WiFi.
I hope this helps move you along in the right direction. I assume you want to really be able to connect to the internet and your BomeBox simultaneously but if not, APIPA mode will work or you could use BomeBox as a hotspot (with a different SSID) and then on your Mac just connect to your BomeBox SSID when you want to switch off of your home network.
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