Yup. I worked on the "Rapport" series of switches at Bell Canada. It was DS1 (Digital Signal 1) out one end and a rack full of Zyxel modems on the other side. The idea was RBOCs (Regional Bell Operating Companies) would put these in their CO (Central Office) and terminate 56k modem signals over the analog "last mile" loop to the customer premises and then do Frame Relay over the phone company's data lines to your ISP.<p>I know Southwest Bell bought a number of them and stuffed them in a closet north of downtown Dallas. During the install I remember having to explain what Ethernet was to their techs. They were EXCELLENT at phone standards, but had decided the data world was threatening and were determined to never learn anything about it.<p>I know that between around '93 and '97 if you dialed AOL from D/FW there was a good chance your call would be terminated somewhere within a mile or two of your house and the bits flowing between your Compaq Presario and AOL would be sent digitally from the local CO to AOL's data center in Sterling, VA.<p>This line of business was (of course) destroyed by consumer DSL and cable modems, but for about 5 years it was fairly popular with the phone companies. ISDN at the time was a bit pricey for most households and a modem is a one-off purchase. Most people I knew using things like AOL or CompuServe were using a hand-me-down 36k modem on a crappy 33MHz 486sx running DOS / Win3.1 / Win95 and were fairly cost-sensitive.
To be clear, this was well known at the time. It was advertised that 56k was for download only and required an ISP that supported it. For those living in rural areas, there often weren’t any local options (long distance was certainly not free in those days). But for those who could get it, it was definitely a big improvement.
TIL why upload on 56k modems were capped on 33.6k. I always wondered about that.
Super interesting stuff!<p>I also remember back in the day that my 56k modem would often only connect at like 48k or so, especially when it was raining. I guess living far out from the city made the connection more noisy?
Isn't it the opposite of the headline? Modems were hamstrung by digital phone lines you didn't know we had. One final trick allowed them to match, but not exceed, those digital lines.
I had made a small career on building Internet Service Providers in California, in the early days, and will never forget how liberating it was to carry my laptop to the Griffith Park observatory with a fully-charged Ricochet modem plugged in, communicating to my house down in Los Feliz, where another Ricochet modem gateway'ed me to the Internet via the house 56k line ..<p>It was truly astonishing to be up there, checking email.<p>A few, what seems very short, years later .. and now it is just normal.
I have to wonder if the cap (theoretical) on the copper wires was more because of the technology standards in play at the time. Surely the copper wires could have handled more if they did not have to carry voice communication (with the old tech specs of the time) any longer?<p>Ok. Searched around.
Here is an article that states old copper could have carried 1 gigabit.<p><a href="https://www.newscientist.com/article/2317040-ordinary-copper-telephone-wire-could-carry-gigabit-broadband-speeds/" rel="nofollow">https://www.newscientist.com/article/2317040-ordinary-copper...</a>
I could tell what connection speed my modem was going to be by the sound of the handshake. There were distinct sounds for all the different modes.<p>I remember us getting our first modeum, it was 800 baud! Then we moved to 2400, 14.4, 33.6 and eventually all the way to 56k.
I remember some ISPs allowing you to "shotgun" two 56k modems for double the speed!<p>Like some other commentors I also fondly remember ISDN. Overall I found it to be finicky. Sometimes one channel would just drop, even if a phone call wasn't coming in. And, in order to use a traditional analog phone with your ISDN line, you needed a special powered "TA" adapter or the phone wouldn't ring when a call came in.
> Using the Digital Signal 0 (DS0) encoding<p>DS0 is not encoding. It's (pseudo) framing.<p>> phone calls became digital with<p>The G.711 encoding in either aLaw or muLaw format.
Now I'm curious about how this worked in my city where we most definitely didn't have anything digital to our phone system at the time. As in, you had to use pulse dialing, and sometimes, rarely, your calls would glitch such that you would hear someone else talking over your call. Yet I remember consistently getting 40-something kbit over that.
I remember the day we got 56K from our ISP. Our modem was 56K (no idea what model, some internal WinModem), but the ISP was limited to 33.6K. Then one day, the connection screech sounded different, and I excitedly pointed this out. Several seconds later, it connected, and lo and behold, we had 66% faster downloads.<p>The fact that all of this worked continues to amaze me, but then, so do mobile phones. I understand at a high level how CDMA works, but it’s just so insane…
Yes these modems were almost-ISDN (minus the razor fast call setup). And required a full digital backend to work. They could only do 56k6 in one direction, to the user too. But they were made for internet access so that didn't really matter.
Man I wish we still had slow connections, given all the dumb crap on webpages these days.<p>Was crazy to think about trying to get your page to load in less than 64k a few years back.