Comment by gerdesj
1 day ago
"where we might as well save the bandwidth"
I come from a world (yesteryear) where a computer had 1KB of RAM (ZX80). I've used links with modems rocking 1200 bps (1200 bits per second). I recall US Robotics modems getting to speeds of 56K - well that was mostly a fib worse than MS doing QA these days. Ooh I could chat with some bloke from Novell on Compuserve.
In 1994ish I was asked to look into this fancy new world wide web thing on the internet. I was working at a UK military college as an IT bod, I was 24. I had a Windows 3.1 PC. I telnetted into a local VAX, then onto the X25 PAD. I used JANET to get to somewhere in the US (NIST) and from there to Switzerland to where this www thing started off. I was using telnet and WAIS and Gopher and then I was apparently using something called "www".
I described this www thing as "a bit wank", which shows what a visionary I am!
Fellow old here, I had several 56k baud modems but even my USR (the best of the bunch) never got more than half way to 56k throughput. Took forever to download shit over BBS...
The real analog copper lines were kind of limited to approx 28K - more or less the nyquist limit. However, the lines at the time were increasingly replaced with digital 64Kbit lines that sampled the analog tone. So, the 56k standard aligned itself to the actual sample times, and that allowed it to reach a 56k bps rate (some time/error tolerance still eats away at your bandwidth)
If you never got more than 24-28k, you likely still had an analog line.
56k was also unidirectional, you had to have special hardware on the other side to send at 56k downstream. The upstream was 33.6kbps I think, and that was in ideal conditions.
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Yeah 28k sounds more closer to what I got when things were going well. I also forget if they were tracking in lower case 'k' (x1000) or upper case 'K' (x1024) units/s which obviously has an effect as well.
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* 56k baud modems but even my USR (the best of the bunch) never got more than half way to 56k throughput*
56k modem standards were asymmetric, the upload rate being half that of the download. In my experience (UK based, calling UK ISPs) 42kbps was usually what I saw, though 46 or even 48k was stable¹ for a while sometimes.
But 42k down was 21k up, so if I was planning to upload anything much I'd set my modem to pretend it as a 36k6 unit: that was more stable and up to that speed things were symmetric (so I got 36k6 up as well as down, better than 24k/23k/21k). I could reliably get a 36k6 link, and it would generally stay up as long as I needed it to.
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[1] sometimes a 48k link would last many minutes then die randomly, forcing my modem to hold back to 42k resulted in much more stable connections
Even then, it required specialized hardware on the ISP side to connect above 33.6kbps at all, and almost never reliably so. I remember telling most of my friends just to get/stick with the 33.6k options. Especially considering the overhead a lot of those higher modems took, most of which were "winmodems" that used a fair amount of CPU overhead insstead of an actual COM/Serial port. It was kind of wild.
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> several 56k baud modems
These were almost definitely 8k baud.
Yes, because at that time, a modem didn't actually talk to a modem over a switched analog line. Instead, line cards digitized the analog phone signal, the digital stream was then routed through the telecom network, and the converted back to analog. So the analog path was actually two short segments. The line cards digitized at 8kHz (enough for 4kHz analog bandwidth), using a logarithmic mapping (u-law? a-law?), and they managed to get 7 bits reliably through the two conversions.
ISDN essentially moved that line card into the consumer's phone. So ISDN "modems" talked directly digital, and got to 64kbit/s.
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In case anyone else is curious, since this is something I was always confused about until I looked it up just now:
"Baud rate" refers to the symbol rate, that is the number of pulses of the analog signal per second. A signal that has two voltage states can convey two bits of information per symbol.
"Bit rate" refers to the amount of digital data conveyed. If there are two states per symbol, then the baud rate and bit rate are equivalent. 56K modems used 7 bits per symbol, so the bit rate was 7x the baud rate.
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Yeah I got baud and bit rates confused. I also don't recall any hayes commands anymore either...
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Confusing baud and bit rates is consistent with actually being there, though.
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> I've used links with modems rocking 1200 bps
Yo, 300 baud, checking in.
Do I hear 110?
+++ATH0
My first modem (from 1987) was 300 baud, but it could be used in a split mode called 75/1200.
Before that I used 50 baud systems in the military as well as civil telex systems.
Mine was 300 baud, probably 1982?
And I felt privileged because the configuration for my TI-99/4A Terminal Emulator (which I believe was called Terminal Emulator) had options for 110 or 300 baud, and I felt lucky to be able to use the "fast" one. :)
My first modem (you always remember your first) had no carrier detection (and no Hayes commands, and no speaker...), so I would dial the number manually, then flip a switch when I heard the remote end pick up and send carrier to get the synchronization started.
It was incredibly exciting at the time.
Ah, the good old days. I remember dialing up local BBSes with QMODEM.
AT&C1&D2S36=7DT*70,,,5551212
PoiZoN BBS Sysop chiming in. I ran the BBS on a free phone line I found in my childhood bedroom. I alerted the phone company and a tech spent a day trying to untangle it, but gave up at the end of his shift. He even stopped by to tell me it wouldn’t be fixed.
I didn’t know the phone number, so I bought a Caller ID box, hooked it to my home line, and phoned home. It wasn’t long before every BBS in town had a listing for it.
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Ha, same! On a TRS-80 Color, nonetheless. But I think I used four times, because no one else in the country had a BBS at the time (small city in Latin America).
It took a couple of years until it would catch on, and by then 1200 and 2400 bps were already the norm - thankfully!
Same year, I tried this cool new "Mosaic" software and thought it was a cool proof of concept, but there was no way this web thing could ever displace gopher
Which was right, today gopher has more users than ever! :)