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Comment by pjc50 | Hacker News Reader

> Ethernet had to adapt to deterministic real-time needs

Without being able to get too into the telco detail, I think the lesson was that hard realtime is both much harder to achieve and not actually needed. People will happily chat over nondeterministic Zoom and Discord.

It's both psychological and slightly paradoxical. Once you let go of saying "the system MUST GUARANTEE this property", you get a much cheaper, better, more versatile and higher bandwidth system that ends up meeting the property anyway.

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I saw a story once, which may well be completely made up, about why AT&T got out of the cell phone business. They had a research project, but reliability was an issue. They couldn't see a way to do better than 1 dropped call in 10,000. Their standard for POTS at the time was 1 in 2 billion.

Seeing that the tech would never be good enough, they sold off the whole thing for cheap. Years later, they bought it back for way, way more money because they desperately needed to get into the cell phone business that was clearly headed to the moon.

I totally understand the pride they had in the reliability of their system, but it turns out that dropped calls just aren't that big of a deal when you can quickly redial and reconnect.

Seems a little sus. AT&T basically created the cellular mobile phone, and built up an analog, then digital system (D-AMPS/TDMA). AT&T sort of sold out the mobile business in 2004 to Cingular (BellSouth) because TDMA was a dead end. They then bought BellSouth back in 2006 and carried on with CDMA.

Those old phones had a long range. It was hard to make small ones because the old AT&T towers were much farther apart, up to 40km. Meanwhile, their competitors focused on smaller coverage areas (e.g. 2km or less for PCS) and better tech (CDMA), and it seemed to pay off.

This is a minor detail, but the "AT&T" that bought BellSouth in 2006 was the AT&T formerly known as SBC which bought the husk of Ma Bell and rebranded itself, i.e. the AT&T we have today.

Yes, AT&T was hollowed out because long lines was the family jewel and it became commodified in the late 90s/early 2000s by overinvestment in competitors.

Early cell phones were so limited it's sort of amazing they gained adoption. They were big (literally the size of a brick), heavy, and expensive. Battery life was poor. The EM radiation was possibly harmful. Due to all of that most mobile phones were permanently installed and could only be used in a car. Plans were either pay-by-the-minute or had pre-paid minutes with expensive charges if you went over. Roaming off your local network was crazy expensive... somthing like dollars per minute. Texting wasn't even a thing at the time; most phones only had a 10-character display. Voice quality was poor and calls often dropped or would not connect.

It wasn't until phones shrank and service got cheaper, that consumer adoption took off. Businesses and early adopters will pay even if the product is inconvenient and costly to use, as long as the benefit exceeds the cost.

Because there was no alternative. Even small suitcase size meant you could make a call from your car instead of driving away to find a payphone.

Payphones were everywhere though. And if you were somewhere that didn't have a payphone, you probably were out of cell phone coverage also. They were a bit more convenient, you could use them without stopping, and you didn't need to have a pocketful of coins (but most people did carry some coins in those days, too). And they were a status symbol.

I remember an absurd ad where a pushcart hot dog vendor was taking orders on the cell phone and I'm like $0.99/min for a $5 or less sale? Yeah the ad was for a service that charged by the tenth of a minute or something but it was still crazy. It was mostly doctors and traveling salespeople that had them.

I love the scene in the beginning of Twin Peaks: Fire Walk With Me with the car phone.

Absolutely not "everywhere". In a city or municipality centre, sure. In the harbour, out on the docks, nada.

> not actually needed

What you need is more that enough bandwidth.

Think of the difference between a highway with few cars versus a highway filled to the brim with cars. In the latter case traffic slows to a crawl even for ambulances.

It seems like it was just cheaper and easier to build more bandwidth than it was to add traffic priority handling to internet connectivity.

And that cheaper bit I think just came from reduced complexity. With things like ATM circuits and other similar highly reliable and predictable methods, they needed a lot of hand holding. You needed to provision an ATM circuit, you needed to make sure across the network that the path was there, capable, maintained, and configured, and you had visibility end to end

That was a selling point, because "hey we guarantee this circuit" but it was also very expensive and labor intensive

Where just dumping your bits into the internet and letting the network figure it out outsourced a lot of that complexity to every hop along the network you didn't own. But, because they care about their networks everyone would (in theory) make sure each hop was healthy, so you didn't need to hand hold your circuit or route completely end to end

> People will happily chat over nondeterministic Zoom and Discord

Only because they don't even know how a good system feels like

You're thinking about normal end user scenarios. Try doing that in a studio environment or perhaps a live production. Even in my home studio I have to use a dedicated Dante network or normal lan broadcast traffic will ruin the day.

Yeah, big differences between an absolute guarantee and "we'll take as much as we can get"

> People will happily chat over nondeterministic Zoom and Discord.

Well, not "happily". (Doesn't every video conference do the "hold on, can you hear me? I have wifi issues" dance every other day?) But it works on a good day.

At work it became mostly flawless. Everybody is used to it and people can jump in calls quickly when chat discussion etc don't suffice. The glitches are on a comparable level to physical meetings where somebody comes late and disturbs all while getting settled or somebody speaking too quiet for the room.

In my club when there is a virtual club meeting however, where people don't have frequent video meetings there is always somebody with trouble ... often the same.

Well, Teams is like that (not "I have wifi issues", but "I have Teams issues"). Even more so after teams.microsoft.com moved to teams.cloud.microsoft - never got the mic or speaker to work after that. Before, it was kind of random.

Zoom, on the other hand.. I have weekly Zoom meetings and never had do to the "can you hear me" thing. Or in fact with basically anything which is not Teams.

In any case.. it's not the network, it's the application/service.

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