Just wanted to pop in and give info on the switch I've been using. This one is probably overkill for most homes, but a solid option for those with lots of cameras:
HP JE007A - 24port 365W poe+ GBe managed switch w/ some L2 features
I bought mine used from ebay for $150 last year, and there are still plenty available for those looking to power lots of cams:
Find many great new & used options and get the best deals for HP JE007A - V1910-24G-PoE - 24 Port Gigabit Network Switch - SAME DAY SHIPPING at the best online prices at eBay! Free shipping for many products!
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This router also has 4 expansion slots for fiber link for those who would need it. The switch is very loud, and contains a total of 9x 40mm delta fans (so swapping quiet fans is an expensive chore). That said, I have the switch running in a closet that regularly exceeds 90F, and it is rock solid reliable.