If I understand your question correctly, it sounds like you're wanting to use something like TCPSer. It was made by Jim Brain, and AFAIK, it only works with Windows. But what it WILL do is take a portion of your internet connection and turn it into individual emulated dialup modems. A lot of people use TCPSer to run BBSs from within Emulators. I had done so in the past and plan to do so again when I have more time to explore how to run either CNet Amiga(Bought v3.05c after it had been out for a while) or setup another C64 BBS.