I have a few Cisco 1841 Routers with T1 Serial CSU/DSU Wic cards. These routers were used for our old T1 lines, etc. I want to try and use them on our network to segment out two portions of the network. Can I do this without purchasing new cards for them? For example, I want to set up a separate segmented network using a different IP scheme (ie. 10.10.10.0/24) which will connect to another network internally (192.168.0.0/22). Any help would be appreciated.