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Comment by dylan604 | Hacker News Reader

Growing up, I lived in the boonies. Even with a 56k modem, the fastest it could go was 33.6k. I got to learn all of the info from the TFA when I was a trying to find out why. That’s also when I learned that some companies had full T1 lines all to themselves for a whopping ~1.5Mbps. Until some makes a call or sends a fax when your top speed drops 64k per phone line being used. It’s also why ISDN didn’t connect at 128k but at 112k since it just used two “bonded” lines of the T1

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> Until some makes a call or sends a fax when your top speed drops 64k per phone line being used.

That wasn’t how it worked. You could have a T1 with certain channels configured for voice and others for data, but the configuration was static — you didn’t get to use the bandwidth from the voice channels when they were idle.

> It’s also why ISDN didn’t connect at 128k but at 112k since it just used two “bonded” lines of the T1

ISDN bearer channels were 8-bit clean. If you bonded both channels of a BRI, you had a 128kbps data path. What you typically couldn’t use was the 16kbps D channel, which was used for signaling.

Correct. And IIRC, IDSL was just ISDN with all three channels dedicated to data. Yielding 144kbps at phenomenal distances from the CO.

IDSL was an ISDN bearer with Frame Relay running on top, it basically didn't use the channelization scheme at all - and IIRC had different framing than a real BRI line.

IDSL used HDLC natively as a frame format. You could run Frame Relay on top of that (or PPP.) Line coding was standard 2B1Q in North America (same as a “regular” ISDN BRI.)

Some ISDN TAs supported data-over-voice for 56kbps per channel. Useful in areas where data calls has per-minute charges but unlimited local "voice" calls were included in the monthly charges.

Right, and some TAs supported data notifications over the D channel. There was also 144kbps IDSL which made use of the D channel bandwidth. And a bunch of other variations.

But, the fundamental channel width was 64kbps and ISDN data calls were not routinely connecting at 56kbps due to robbed-bit signaling, which the GP comment claimed.

Twin bonded ISDN lines were my only option for anything faster than 33.6k. “You too could have had 128k for the low monthly price of $250 + cost of two phone lines + cost of equipment + labor”. When I finally moved to somewhere that had cable (and cable internet at 1.5mbps) I vowed never to return to the sticks.

Then Elon came along… Starlink is probably one of the most useful inventions next to the lightbulb, DC current, Solar Cells, Toilets, desalination/ro and the WWW. I’ve gotten 100mb+ out in places where you have no cell service, no humans, no life, and no way of contacting anyone if in trouble. Starlink kept the connection no problem.

I’m excited for the future if we can just get over our differences. XR, Starlink, EV’s, Highspeed rail, Electric planes, Mars…

I just dont see how starlink makes money in the long term, without massive government subsidy like Iridium gets. Elon's seeming unwillingness to play nice with the federal government in regards to this harms Starlink's ongoing viability.

Technically, it's a pretty neat trick - architecturally, it works just like any cellular network, except the power is moving, not the subscriber.

The government has been trying to subsidize ISPs to expand broadband to more rural areas, but that has been a failure compared to Starlink which actually exists.

The same government that refused to pay up until they had their arms twisted?

The unwillingness is from the government

> You too could have had 128k for the low monthly price of $250 + cost of two phone lines + cost of equipment + labor”.

+ per minute billing from your telco and your ISP.

Oh man, so true. $350 worth of internet hourly charges when my mother was livid and asked me what the hell I was doing all the time online running up a bill like that.

I simply replied “Air Warrior 3”.

T1's were so mind numbingly expensive and ISDNs always seemed like a cheaper but insulting value. Same bandwidth as two modems, I ended up holding out for 'broadband' and making due with two phone lines for a few years.

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