|That would be dual WAN port router [not wap] which would narrow you down to two lan gateways. |
You should not be allowing "guest" access to your network. if you want to provide them internet service than set one of the 4 dsl links/router to provide open wireless access. You may even want to put a printer on the guest network for their use.
It would most likely be more cost effective to drop two of the dsl lines and up the bandwith on the remaining internal network dsl. This would make your job easier and reduce the network complexity which will bite you in the butt if things go haywire.
Yes you will have to either manually set every ip address and gateway on each pc to manually balance the internet access or do mac filtering on the routers to have the same results.
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