I seen another post where the guy installed a dry box outside with a POE switch inside it so he would only have one wire coming back into the house instead of one for each camera,
Would this really work? Seems like if you had to many cameras the one wire may get saturated.
Cameras, while comparatively data intensive, are not that data intensive. Assuming a gigabit uplink I'd guess that it would take 25, or more, 8MP cameras running at high bit and frame rates to even start to approach the 1 gig bandwidth of the switch. It's far more likely that the switch, itself, will be overloaded before the gig is reached.
My big concern would be electrical isolation to prevent spikes from outside getting into the system. It would be safer to use a fiber link, rather than copper, from the remote, outside, switch to the inside network. Alternatley, for isolation, a dedicated RF link can support 10 cameras, or more depending on resolution and bit rates, fairly easily and provide the same isolation.
