Aside from immunity to radio signal jamming, there's no worrying about batteries/charging or ugly wall warts. You can also power your PoE switch from a UPS to survive power outages.
It's also vendor agnostic and fairly future proof. What I mean is while you might have lock-in with cameras/NVR today, you aren't locked in forever; worst case is you may be forced to replace everything but the wiring, but that's by far the hardest part to do in a finished house. The Cat5/6/7 will be useful for the foreseeable future.
More flexible in some ways, I’m using 1 port of my 8-way injector to add PoE to the WAN interface of my router. In conjunction with an active PoE “splitter” on the far end I can remotely power the GPON modem on the other side of the house and power everything from one UPS.
I also made sure to get a Mode A “gigabit” injector in order to power 2x PoE cameras in a location with a single Cat6 drop. On the far end there’s just a passive splitter, each camera only gets 2 pairs which run both 100Mbit Ethernet and PoE. Cheaper “non-gigabit” PoE Mode B injectors save a buck by omitting the isolation transformers and instead inject DC onto the spare pairs, so not compatible with pair scavenging.
MikroTik’s PoE switches also use Mode B. They’re gigabit so have to include the isolation transformers anyway, presumably this is due to their ability to operate in 24V passive PoE mode. I was going to get a MikroTik switch but my pair scavenging requirements drove me down the path of a separate multi-port injector, which worked out to be a lot cheaper too!
8 port injector with a decently powerful 56V power supply was approx $100 via AliExpress.
Only drawback is a bit more cabling and no ability to remote power cycle an individual port.
I just installed an Amcrest doorbell which took me like 10 minutes. I'm using it with Scrypted to connect it to HomeKit. I didn't install it for security reasons. My old doorbell switch was broken and I figured as long as I needed to replace it, it would be nice to see what the heck my dog is constantly barking about.
If I wanted something for security reasons, I'd indeed use a PoE camera, but it wouldn't be a doorbell cam. There's very few PoE doorbell cameras in any case and they are quite a bit more expensive. And pulling an ethernet cable to the doorbell switch location would be non-trivial.
The tedium/difficulty/expense of running cabling through walls and crawl spaces is something a lot of tech people seem to take for granted. Wireless is convenient(ish), particularly compared to the aforementioned, so most people are naturally going to gravitate towards it if that serves purpose.
Also, ethernet cabling available right at the front door is a security concern in itself. You need to be knowledgable of networking and have appropriate networking hardware to properly secure it against physical attacks.
This technology could just come built into these cameras which would be the responsible thing to do.
https://www.doorbird.com/downloads/datasheet_a1071_it.pd
It’s expensive, not weatherproof, and hard to order. Same for the one made by 2N. These both recycle old DSL technology I believe.
How difficult it is to install also depends on how your doorbell circuit is wired. Mine goes from a transformer in my basement to a switch on my door and from there to two chimes with a junction hidden somewhere. For these converters to work you need a straight run end to end.
One mitigation is to secure the physical camera, e.g. Axis P1204 can separate the camera lens by 25 feet from the camera with SD card, which can be located inside a locked enclosure/safe/room.
The cameras run on a separate wireless network and save to an SD card in the base station. You can also do RTSP streams.
> Microwave ovens are not tuned to any specific resonance frequency for water molecules in the food, but rather produce a broad spectrum of frequencies, cooking food via dielectric heating of polar molecules, including water. Several absorption peaks for water lie within the microwave range, and while it is true that these peaks are caused by quantization of molecular energy levels corresponding to a single frequency, water absorbs radiation across the entire microwave spectrum.