This question is probably 20 years too late. I have a requirement where a bunch of analog phone lines will connect using dialup modem to my linux/windows server, in order to communicate. Just like we all did prior to broadband. This is for use in remote areas that don't have data connection. The termination on the server side will be ISDN E1. What is the modem hardware used by the ISPs to terminate the E1? I prefer not to demux the whole E1 into 30 analog lines and feed it to analog modems.
Will this work? https://www.dialogic.com/high-density-modems-e1-t1