These days most if not all consumer-grade units combine the router and the modem into one box, so that a "cable router" won't work with DSL, a "DSL router" won't work with cable, and neither will work with dial-up although many do have a "WAN port" to which you can connect a dial-up modem. My ISP calls these combination units "gateways" and they often include wireless capability (as did the WRT254 for that matter).
However standalone dial-up modems themselves are difficult to find these days, and the ones that were built into recent computers (but not in the past couple of years) don't have any way to get the router in between the modem and the computer. In such a case, creating a "software router" within the computer as described in the original how-to article is the only way to travel...
Jim Kyle in Oklahoma, USA
Linux Counter #259718
Howto mark thread: https://wiki.ubuntu.com/UnansweredPo.../SolvedThreads
I found this article, which i found helpful.