Many, if not most decent models have a tamper switch for that purpose. Connect it to alarm system and it will sound immediately after someone tears the doorbell from the wall.
1 Like
That’s like to have a keyless system for cars which is unsafe (allows third persons to access your car) but then just say: “Well, don’t mind! Our car has a sirene 
” 
Why the need for a working/safe door lock if you just can use a steering wheel lock? 
Well, if alarm sounds or goes to police or security company…
It’s not exactly 2 seconds to unscrew device, open hacking device, plug it in, connect, sniff data,…
There’s a limit where security becomes obsession…no matter what you do there’s only so much you can do.
I’m surprised nobody has mentioned 802.1x. VLANs are not really the right tool for the job in this context. Like, VLANs are more of a network segmentation and design tool, not a security boundary. They can be an integral part of a secure network, but not in isolation (imo). If you want to control who can access the port, you need port-based access control (802.1x) and a camera which can do that (which Reolink cameras cannot).
If your threat model warrants it, get a new doorbell that implements proper security protocols. Otherwise, a VLAN, MAC address allowlisting, and further defense in depth is your best option. It’s not a great option (except for defense in depth, always do that), but it’ll keep honest people and incompetent fools out of your network. Determined crooks will break a window not covered by a camera, or they’ll snatch you and use your fingerprint on your phone so they can disable your security system. If your threat model includes that, then you have a very exciting life!
Edit: for example, this Axis video intercom implements 802.1x: AXIS I8116-E Network Video Intercom | Axis Communications
I’m sure it’s expensive (it’s like $900), but it’s worth it if your threat model demands it.
Right, more over an automation which even check if it’s “available/powered on” , if Not, turn of the switch/router-port ( If that feature is available, ofcause )