An update to my dial-up ISP project. I got a two node modem pool working a PCI card to add more serial ports. Instead of my Verizon line, I patched these modems into my PBX running asterisk with a Grandstream ATA with 4 internal lines. The PBX takes incoming calls from a new number and uses a basic hunt group to connect to caller to the next free line.

Got a dialup modem? Feel free to give a call and let me know what OS you are using, how it goes. Details at

@Famicoman Have you been able to get the modems to talk to each other through SIP? I played a lot with that and it took some doing. I have grandstream HT702's hooked to my Panasonic PBX. About 300 was all I could do reliably to the SDF dial in number.

Sign in to participate in the conversation
Mastodon @ SDF

"I appreciate SDF but it's a general-purpose server and the name doesn't make it obvious that it's about art." - Eugen Rochko