I know the SmartHub VMB4540 has a USB 2.0 port but are there any technical limitations? Looking at USB flash drives it seems like there is a wide range of devices in terms of transfer speeds so not sure if there is a minimal speed needed for 3 cameras recording 2k video.
So if I can't find one with decent xfer speeds, storage and price point I think an external HDD would be better since they provide better xfer speeds. Can the SmartHub power an external HDD via USB? It appears that most USB HDD's are bus powered.
Looking at USB flash drives it seems like there is a wide range of devices in terms of transfer speeds so not sure if there is a minimal speed needed for 3 cameras recording 2k video.
You don't need a lot of speed. Arlo says 2 megabits per camera, so 6 megabits total. That number is conservative (on the high side). Even so, it's only .75 megabytes per second (6/8). Any flash drive should be able to handle that.
While you can use a hard drive, you generally don't need to. At 2 megabits per second, even a 32 GB flash drive can hold about 36 hours of recordings.
Great, thanks @StephenB. I'm still interested in the HDD if the USB port can power it. Looking at the reviews of many USB flash drives reliability is more of an issue. I've had a number of them but only use them for copying files, installing ISO's or whatnot. I don't use them constantly, so never experienced failures.
I'm still interested in the HDD if the USB port can power it.
Power could be a problem, particularly if you get a USB 3 drive (as most are). So I'd look for a drive that has an optional power adapter, just in case.
The power spec for USB 2 is 500 ma - though the power requirements for many USB drives aren't stated in their datasheets.
Looking at the reviews of many USB flash drives reliability is more of an issue.
Obviously reliability does vary across brands (and there are counterfeits out there).. I've found mine to be quite reliable (and they are both cheaper and less cumbersome than hard drives or SSDs). Most of mine happen to be Sandisk.