If you have two DSL connections and two normal routers, you can run two networks with one trading machine on fallover connected via dual ethernet ports on the mother board. You just connect one network cable from each router to the motherboard. One network will always be up.
This is a good cheap option if you don't need all your machines connected to the net all the time.
Runningbear
This is a good cheap option if you don't need all your machines connected to the net all the time.
Runningbear