Live data from Hacker News

What Was ISDN?

tedium.co

151–160 of 164 posts

Re: What Was ISDN?

#151

The article addresses the big miscalculation by the telecoms, as I see it, though somewhat obliquely. In the telecom world, the telecom was the network. If you wanted to exchange data with someone, you placed a call to someone directly. Everything was envisioned as some form of point to point session between subscribers. Whatever it was, it was one subscriber contacting another. The telecoms didn’t really conceive of…

I worked at an ISDN adapter company in the late 1990s. Apparently, one customer a couple of years earlier did use ISDN as their LAN technology. Each PC with an adaptor (to the joy of my employer, this customer was not small), using the PBX as network switch. I have no idea what software they used. Probably some CAPI-based file transfer. The extended version of that, using ATM-based BISDN, was the telcos' vision of networking.

Re: What Was ISDN?

#152

Man, the idea that ISDN was going to last 50 years has to be one of the bleakest Bellhead memes I think I've ever heard. "You will only have 144kbps and be happy."

It's a service framework for subscriber based circuit switched connections. The modulation format is separate and I doubt they expected to keep such a meager encoding for the long predicted life of the network. The error was in not seeing packed switched networks as the clear winner not in choosing a modulation scheme that was designed to bring maximum bandwidth over existing copper infrastructure. In any case, the s…

Actually, it was envisioned that you'd use the D channel for packet switched data traffic (not IP, more like X.25). Why would a private person use more than 16 kbit/s for a home computer? Much more important to have two high-quality voice lines! And we are busily working on ATM-based Broadband-ISDN to even make high quality video calls and TV available! Just you wait!

Re: What Was ISDN?

#153
post #77

I find it much more amazing that T1 dates back to 1962. What could talk at 1.5mbps in 1962? Mainframes I guess? Then there’s the fact that this speed remained fairly state or the art until DSL and then cable modems. There was also T3 in the 1990s for a whopping 45mbps. I worked for a bit for an ISP in Cincinnati in college that had one of those running to a data center. That DC was full of racks of Windows NT machine…

E1 (2Mbit/s) lines were used to connect data centers in the early 1990's.. Man, to think what you could at home with such bandwidth. Maybe even video!

Re: What Was ISDN?

#154
post #115

Earlier quoted context omitted.

Ahh, good ol’ pair gain, where the ILEC would basically share one circuit between 2 houses. Saves money from not having to run a second circuit, plus the sound quality isn’t too awful as long as you’re deaf. I also worked at an ISP. Customers would sometimes call to complain about how much we must suck because their shiny new 56k modem wouldn’t train up past 28.8, and it couldn’t possibly be on their end because they…

We're going to need a PTSD trigger warning on this thread if we keep this up. Did residential dial up support from 95-00, and got to experience all those disasters. Another fun one is when you serve at the edge of two different phone companies and they didn't have enough cross connect service between the two for all the long running dial up connections. Yea, your modem banks aren't full, but your customers are gettin…

Oh lawdy. I can't say that surprises me.

Re: What Was ISDN?

#155
post #140

Earlier quoted context omitted.

Ahh, good ol’ pair gain, where the ILEC would basically share one circuit between 2 houses. Saves money from not having to run a second circuit, plus the sound quality isn’t too awful as long as you’re deaf. I also worked at an ISP. Customers would sometimes call to complain about how much we must suck because their shiny new 56k modem wouldn’t train up past 28.8, and it couldn’t possibly be on their end because they…

> Winmodem. Memories! An old job bulk-bought a ton of cheap "home" PCs (Compaq Presario) to use as Citrix desktop clients; the included modem was a winmodem. We discovered the CPU in the PCs couldn't reliably run the Citrix software and maintain a modem connection at the same time. We ended up having to buy external modems (and later network cards) for all the presarios. Thankfully we learned from the experience and…

Ouch, LOL! There were so many tech support calls about such things. "I paid a good $30 for this new 56k modem, and I still can't download more than 2KBps when the screen saver kicks in. You guys suck!" "Did you get that from the shelf next to the $200 USR modems?" "I did. Those are rip-offs!" "Mmm-hmm."

Re: What Was ISDN?

#156
post #138

Earlier quoted context omitted.

Ahh, good ol’ pair gain, where the ILEC would basically share one circuit between 2 houses. Saves money from not having to run a second circuit, plus the sound quality isn’t too awful as long as you’re deaf. I also worked at an ISP. Customers would sometimes call to complain about how much we must suck because their shiny new 56k modem wouldn’t train up past 28.8, and it couldn’t possibly be on their end because they…

Is this really why I could never go past 28.8k? I was 16 at that time, always wondered why - and experienced this in a few different homes until we switched to DSL.

It's very possible, especially if you lived in even a slightly rural-ish setting, like outside the city proper. There are so many reasons that could cause it, though. If you could hear any crackle or hissing during voice phone calls, that would be enough line noise to force a lower speed train-up.

Re: What Was ISDN?

#158

We networked our nerd house in the early/mid 90s, using an ISDN terminal to get that blazing fast 128kbps. Back then, people weren't constantly streaming video, so most of the time when you were downloading stuff (kernel source, Linux distros, funet.fi, sunsite.unc.edu, etc.) you got the whole 128k to yourself. Most people at the phone company had no idea what ISDN was, so it took a while to find a technician there w…

Before we lived together my wife moved into a flat and got a landline so she could get online. The phone company installed an ISDN line, great. But when they installed it they never properly explained it to her, so she was using her 56k modem on the ISDN line! I visited and saw how she was connecting, I then showed her that by plugging in the USB connection on the ISDN TA, she could get faster speed and a quicker connection. I don't think she used 128k, but single channel 64k was still a big step up for no extra cost.

Re: What Was ISDN?

#159

Earlier quoted context omitted.

It's a service framework for subscriber based circuit switched connections. The modulation format is separate and I doubt they expected to keep such a meager encoding for the long predicted life of the network. The error was in not seeing packed switched networks as the clear winner not in choosing a modulation scheme that was designed to bring maximum bandwidth over existing copper infrastructure. In any case, the s…

Actually, it was envisioned that you'd use the D channel for packet switched data traffic (not IP, more like X.25). Why would a private person use more than 16 kbit/s for a home computer? Much more important to have two high-quality voice lines! And we are busily working on ATM-based Broadband-ISDN to even make high quality video calls and TV available! Just you wait!

That's somehow even more bleaker and more Bellheaded.

Re: What Was ISDN?

#160

That brings back fond memories. In high school (a long time ago), I coded up a client-server application in Perl/Delphi to utilize the ISDN D-channel to transmit small amounts of data by repeatedly dialing a destination, using the call initiation metadata to communicate, and then hanging up before the call got established. In Europe at that time, every call (even local ones) started getting billed as soon as the dial…

This is the coolest, old school hacker tech I've heard in a while
Post reply on HN