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rahimnathwani

It seems like for a basic setup I need:

- an intel-based PC (can be a minipc, doesn't need a powerful CPU)

- a USB Coral TPU ($60)

- some wired PoE cameras (from $60 each)

My question: what do people typically use to power the cameras? A single PoE switch, or multiple PoE injectors?

My Arlo Pro 2 cameras are apparently EOL and might stop receiving free cloud services in a couple of months. So this seems like a good time to upgrade to higher resolution cameras.

(The Frigate docs advise against using Wi-Fi cameras, which would otherwise be my preference.)

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I just have a PoE switch. It's actually easier to run ethernet than power, especially outside. Clogging up your WiFi spectrum with megabits of constant video seems like a terrible idea.

> Clogging up your WiFi spectrum with megabits of constant video seems like a terrible idea.

Yes, that's the thing I like about the Arlo system I have now: it has its own wifi network so, even if it's using spectrum, it's probably not affecting my LAN throughput.

> It's actually easier to run ethernet than power, especially outside.

This is true, but the house where I live already has power available everywhere I might need a camera. The thing I don't like about running new cables is the need to drill holes through exterior walls.

Your LAN can handle it :)

If the current setup can't, plugging the cameras and the NVR into a separate switch and none of that traffic will go near the rest of your LAN.

Wifi on the other hand, there's really no (practical) segregation to speak of - the spectrum has limited bandwidth, it doesn't matter if it's a different SSID / wifi network, it'll affect your Wifi!

I don't get why people don't get that part. What they mean by "Up to 1234 Mbps" on the box is "1234 Mbps shared". It's a giant wire occupying 1/4 mile around the AP, whereas, in wired Ethernet it's 1Gbps per link per direction.

A GbE switch with wire-rate transfer guarantee can handle 1Gbps traffic between arbitrary combination of ports. All the camera traffic coming from port 9 to 16 going to NVR on port 7 have no impact to traffic between upstream router on port 26 and your PCs on port 3 and 5. That cannot happen with Wi-Fi because everything is inherently on the same shared port 1(sometimes literally); each 4Mbps incoming is 4Mbps of download speed taken from your laptop. Double if destination is also on Wi-Fi.

This might be fine if there's just few cameras, but it's something to be aware of.

If you live in a sufficiently low density area (rural or suburban with large lots) you can put the two networks on different channels and they won’t meaningfully interfere with each order.

The chances are, if you live somewhere like that, somewhere that actually has a low noise floor for RF, then you likely also have a lot of space to cover with your wifi - and that means sacrificing range (via additional access points) for the second network..

For me: Wifi is great! But, whenever it's practical, I avoid it... Everything with it is a tradeoff!

> Yes, that's the thing I like about the Arlo system I have now: it has its own wifi network so, even if it's using spectrum, it's probably not affecting my LAN throughput.

Wifi6 is changing a lot of this, but generally speaking Wifi performance is not optimized for media style traffic. Media traffic does best with low jitter (variance of latency) as this tends to keep buffer sizes low and avoids dropping frames. Wifi is not very good at low jitter, and though Wifi6 is a lot better than previous Wifi standards, it's still much harder to keep jitter low on Wifi than it is on a LAN. On top of that, as the sibling commenter says, even if you have a separate Wifi network, spectrum doesn't segment that neatly. Wireless traffic uses multiplexing methods (there are several and if you're interested, the methods are fascinating [1]) to roughly use the same spectrum. These multiplexing methods obviously need to do more work the more traffic there is on the spectrum.

If you can route your media traffic through LAN do it. Obviously as you say, running new cable is a lot of work so it's understandable why you use Wifi. But LAN is just so much better that if you have the time/money (doing it yourself/hiring someone) to do it, I highly recommend you do.

[1]: https://www.intechopen.com/chapters/66562

> it has its own wifi network so, even if it's using spectrum, it's probably not affecting my LAN throughput

Unless you're using dedicated APs it is absolutely affecting your other wifi users.

The Arlo system generally does use its own dedicated APs.

Arlo’s base station is an AP.

Not just that but if a thief is going to break into your home, a wifi hammer will render a lot of smarthome gear including cameras useless.

Did you mean "jammer" or is there something new called a "wifi hammer"? If so, it sounds interesting.

Haha, yes jammer. Fat thumbs.

If you have a newer intel-based PC, you might not even need the Coral. Frigate added support for Intel's OpenVINO. They're also adding support for the RK3588's rockchip npu, but it's still newer so I wouldn't recommend unless you like tinkering.

For PoE, I'd just do whatever is convenient. I've done setups with 2 PoE switches before so I could just run one cable between the front/back and then branch out from there.

Single PoE switch with cameras on a VLAN (so they don't have internet access). I use my old framework main board (yay for reuse!). Started with a USB Coral but switched to NVMe, which is more reliable passing through to a VM.

Frigate links some Dahua camera recommendations in their documentation: https://docs.frigate.video/frigate/hardware/

I installed them and they've been rock solid. Low light performance is excellent. The turret form factor is nice and unobtrusive.

Last time I looked at this the Coral devices were out of stock and price gouged. Looks like I can at least order now with a lead time of 22 weeks from mouser.

https://coral.ai/products/m2-accelerator-dual-edgetpu/

Depends on the version. They have thousands of m.2 in stock.

https://www.mouser.com/c/?q=coral

Whoops I misread the factory lead time as the estimate time :)

No worries. I picked up some nvme to make a low power frigate box when I saw the USB is often unobtainium. Figuring out the whole m.2 keying scheme vs the ports I have took the longest of it.

I found that one key type is for wifi daughter cards so I was able to save a pcie slot or nvme slot using that in the small form factor host.

> what do people typically use to power the cameras? A single PoE switch, or multiple PoE injectors?

It basically doesn't matter at all - I have a mixture of both in my home, multiple PoE switches and multiple PoE injectors for things like cameras, wireless APs etc. Use whatever fits needs/budget/location, you don't have to go nuts buying a single high end PoE switch. There's often good deals to be had on used PoE switches on ebay etc too if really budget conscious.

The only real advantage of going with a single or fewer PoE switches is you have less things to put on a UPS, if you require the system to still work when power goes down. A UPS that can run say 4 cameras, the PoE switch and a system running Frigate for more than a few hours can get pretty expensive too, in my experience - most cheap UPSes are designed to get you enough power to save some files and shutdown a PC in a matter of minutes, not hours.

Cheap intel box with a Coral runs Frigate fantastically, and if a tower build plenty of room for internal storage drives.

Yeah, consumer UPSs tend to scale their inverter capacity along with their battery capacity, which means if you're shopping for huge capacity for long runtime, you end up paying extra for a huge inverter you don't need.

I've gone the other route, with a simple power supply that charges an ever-evolving fleet of whatever cheap 12-volt batteries aren't doing anything else, which then feeds DC-DC converters for the various loads. For stuff that's natively 12-volt like my wifi router and cable modem, I just run those directly off the battery rail.

This setup is quiet, efficient, and presently runs the modem, router, service pi, and my RIPE Atlas probe, for somewhere upwards of 20 hours, for something like $150. If I added a 12v-to-48v converter and a small PoE switch feeding a few cameras, it would probably cut the runtime in half, but I could just throw more battery at it for pennies on the watt-hour.

Single PoE switch works well, they are inexpensive. If you have Poe injectors that can work too.

Wifi cameras are more for convenience than reliability or dependancy.

Doesn’t have to be PoE cameras. I use wifi cameras too, pretty much any camera with rtsp/onvif would work.

Chances are, a single switch is more cost effective than multiple injectors. But you also need Ethernet routed throughout your house. One alternative is to have the G.hn (powerline) adapter with PoE. This way, you can be both network and power with one plug without wiring your house.

Wi-Fi cameras are not a great idea. Sure, they are convenient, but Wi-Fi is a shared access medium (every device on, say, channel 11, has to “cooperate” with all the other devices about when it can transmit, including devices on neighboring SSIDs) and something that is constantly streaming video (or worse, multiple devices!) is going to quickly consume available bandwidth and offer a poor Wi-Fi experience. (But most people only care about convenience.) Plus, Wi-Fi is easily jammed, which is not great from a security perspective.

Ehh, I have a mix of 4K and 2K cameras, it hasn’t been much of an issue. I run OPNsense with a single EAP670 and there hasn’t been much performance degradation. PoE is definitely ideal but not an option for many, including me since I rent. I think the G.hn plugs are probably my best option for PoE if I really needed it.

Edit: not sure why you’re being downvoted

If you're happy with your wifi cameras' performance with Frigate, I'd love a recommendation.

I have a mix of reolink and amcrest ones, I can grab the models later tonight when I’m at my computer

Please do, also looking for recommendations :)

I have a variety of PoE power supplies based on where all my wires are running. I have one PoE switch near my main router that goes directly to a few cams. I have a second PoE switch in my living room that hooks into one in-house ethernet port and splits/powers two outdoor cams. Then I have a number of WiFi cams still where it wasn't convenient to get ethernet.

I am using it all: PoE switch, then couple injectors where it is needed for some specific reason and then also PoE splitters (one cable leaving from PoE switch, going to splitter and then to 4 different PoE cameras, powering everything with one PoE output from switch).

I would not use WiFi cameras. Standard RTSP PoE h264 is the way to go.

Check out the Nvidia Tesla P4. It's basically an uncooled low profile 1080 8GB.

I have a single PoE switch for my ubiquiti cameras and polycom voip phones. My original need for the PoE switch was actually the access points and not the cameras but I slowly converted from nest to these.

PoE switch with a big UPS so that recording does not stop in case of power outages.

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