I am about to have a rather "different" system I'm putting together.
It will have 6 independent IP camera systems (6 NVR's) with about 40 cameras across them (three with 4 cameras, two with 6 cameras and a 14+ camera system). There will be 5-8 PC's and VOIP phones with a PBX box.
I'm thinking to isolate camera traffic I should employ multiple POE switches (all cameras and VOIP phones will be powered via POE). I'd have each NVR connected to the switch that connected directly to the cameras that it monitored. This would all then be tied to a larger switch which would tie in the phones and computers as well. I'd be able to remotely log into any of the camera systems and only then would the traffic "contaminate" the rest of the network. Calls would be minimal as would most of the PC traffic. The cameras are also not for security or theft monitoring, just for generally keeping an eye on what is going on in their respective regions.
I've drawn up (probably pretty poorly) what I think represents what I have in my head.
I'm also open to suggestions for switches, but I'd like to do this very budget conscious minded. I've been leaning towards Zyxell switches but not married to them.