Merging OpenWrt router with LAN behind WAN

Hello,
maybe what I want to achieve is already described somewhere in this forum or in one of the documentations / blogs (...) about OpenWrt, but I'm not sure what the right technical term is - so I'm not really sure to what I need to look for.

My scenario and what I want to achieve is the following:
I have a cable model including a router (LAN + Wifi) in my basement, which provides a 192.168.178.x LAN (including the Wifi in the same subnet). In my living room I have a Wifi router running OpenWrt, which is connected via network cable with my cable modem in the basement via its physical WAN port.
Currently the OpenWrt router creates its own LAN + Wifi (192.168.1.x) and NATs its traffic to the cable modem's LAN. (OpenWrt uses DHCP from my cable model to get an own IP in the "basement LAN", configuring the cable model as default gateway etc.
Pretty default configuration so far, I assume.

But what I want instead is that the LAN + Wifi from my OpenWrt is in the same LAN as my cable modem provides; so that I have one "large" 192.168.178.x network and all devices, connected either to LAN/wifi from my cable modem or LAN/wifi from OpenWrt can see/reach its other. So basically 'joining' both networks to one single network.
Is that referred as "bridging" (instead of NAT)?
Or is this something else?

Any hints / tips / links how I can achieve this?

Thanks and kind regards,
Fool

you want https://openwrt.org/docs/guide-user/network/wifi/dumbap

Thank you very much, that is exactly what I was looking for!

This topic was automatically closed 10 days after the last reply. New replies are no longer allowed.