Do You Remember ISDN?
youtube.comHad ISDN in the mid-90s back when I worked for an ISP. Wasn't expensive from my telco, 40 1996 dollars a month and the cost of a Motorola BitSURFR Pro. Got dial-up bonding working on the ISP side. It could "ring through" one of the B-channels when a call came in and stay connected on the other. A wonderful time.
I had a very similar experience. For 1995 it was really quite amazing! Loved how quickly it connected ("I never have to listen to a pair of modems sniff each others butts again!"), and that I could place/receive a call while still being online. Also, the voice quality really was superior, even when receiving a call from a regular POTS call on the other end.
Unfortunately, after the first year of having it, US West (Omaha Nebraska USA telco) started "actively discouraging" ISDN (source, I worked at US West at the time and was asking a sales tech about it). I had wanted to move to a larger apartment in the same building, but doing so would have increased my ISDN cost from $40/mo to by-the-minute $400-ish/mo.
I used a Motorola Bitsurfer on Linux. But my other computer, an HP 9000s712 ("Gecko") had an ISDN modem that was SCSI. That seemed like a weird choice, but their serial port was only rated up to 115.2K so it was the only choice for 128K.
I remember FSOL ISDN https://www.youtube.com/watch?v=VAuMvNt4dr0
Sure. The first internet connection where I worked in the 1990s was ISDN with (I think) an Ascend P50 router. Don't remember what it cost. We used the ISDN strictly for data, not also voice, which was still provided over POTS lines.
Was next upgraded to a VDSL connection that ran at T1 speed, 1.544 Mbps.
I remember. It was very expensive for not a lot of extra bandwidth. You also needed a special ISDN phone or a, again expensive, box to convert the signal to normal POTS.
Not long after the cable company started offering 'broadband' at 115 kbps, quickly upgraded to 512kbps.
ISDN was a complete non-starter in my locale.
In my locale it was much cheaper, because of massive push via subsidies from former gov-telco. We also had 2 x 64kb/s channels, for 128kb/s bundled(dynamically/on demand), plus signalling channel. Since it was so widespread you actually had a chance to enjoy very good voice quality, which often is still unsurpassed, today. Especially regarding latency. Again because of the wide availability, the not so special phones weren't that expensive, and adapter boxes neither. But nobody wanted these anyway, because old phones didn't give the good voice quality.
Oh yeah, we had it in our house because my gf at the time was a tech for an ISP. IIRC, that was the first "broadband" we had, and was replaced by DSL shortly thereafter.