Ok we have a cisco 1841 router with 4 fast ethernet ports. We have a flex t1 that everything come and goes through. We want to add a cable modem and attach it to one of the other ethenet ports available and have all vpn traffics,and all internet traffics come and go through that port. I have not been able to figure this out. I know the easy way is to purchase another router and make all computer except mail servers gateway to point to the new router. Just seems I should be able to accomplish this with a 4 port router..