I’ve been enjoying tinkering with dialup over POTS and VoIP for a few years now. I don’t miss messing around with serial ports, dodgy UARTS and now USB to Serial converters that behave “funny” (brain dead DCD/DCE etc.). A friend dropped off some old Cisco gear and thus a dialup gateway with menu to some local bulletin boards was born.
I’ll get around to posting an example configuration as it could come in handy. What I’m really interested in is getting an Adtran 900E (or some other SIP to PRI converter) and a DVM module in the Cisco I’m experimenting with – the theory being that the Cisco will see a native PRI and offer up full 56K. But for now and until my play budget expands to allow such experimentation (hey eBay is cheap) – I can often connect to the Cisco from my USR Courier at “9600/ARQ/V34/LAPM/V42BIS” using VoIP.
(I can get up to 32K to other systems FWIW and yes, connectivity is way more stable over a traditional POTS land line)
- https://asham.rocks/wp-content/uploads/sites/5/2025/06/cisco-WIC-1AM-V2-WIC-2AM-V2-modules.pdf
- https://asham.rocks/wp-content/uploads/sites/5/2025/06/ccmigration_09186a00801e6fc4.pdf
For testing connectivity these numbers can also be used:
- 1 (303) 494-4774 – NIST Time Server
- 1 613-366-0013 – National Capital FreeNet
- any number of other active modem lines out there
