I'm thinking on a system which needs up to 10 wireless cameras, and the same number of cheap computers, so each can display the live feed of one particular camera. One wireless router is planned to do the job, but I would like to think preemptively in the case that one router will not have enough bandwidth for the 10 live feeds with good image quality and frame rate. In this case, what is the simplest and best solution for another router? Just two parallel systems, like 5 cameras+computers on one of them, and 5 on the other? Or is there a simple solution for all 10 to be able to use any of the two routers, depending on load?
So if you were using the 2.4GHz spectrum of the 802.11n (or g) protocol then you could have three Wifi routers that wouldn't overlap each others wireless signal. This is assuming they are within a 100ft (or so) of each other where they would cause interference on the same channel.
Advanced: if both computers and cameras are wireless, then to prevent potential bandwidth saturation buy nice dual-band wifi routers (netgear or linksys) and set it up so computers are on 5GHz and cameras are on 2.4GHz. You'll need higher-end wifi cards in the computers to support 5GHz.