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Bob Metcalfe wins Turing Award

amturing.acm.org

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Re: Bob Metcalfe wins Turing Award

#81
post #64

Earlier quoted context omitted.

I remember paying about $1000 per port for 100 megabit switches.

Ha! But they delivered that much value (or more), so the market supported the price until supply flooded. We could do worse for a transformative technology ranking metric than "How overpriced was this when first released?" (significant look at Nvidia cards)

I had a bunch of workloads that quite literally got cut down to about 15% or so of the original runtime (a cluster compressing a whole archive of CDs for a large broadcaster) so I happily paid up. But still... $1000 / port!!

And here I have sitting next to me a 48 port gigabit switch that cost 15% of what that 100 megabit switch cost in 1996 or so. Iirc it was one of the first D-link products I bought, it definitely wasn't great (it ran pretty hot) but it worked quite well enough. Amazing progress.

Re: Bob Metcalfe wins Turing Award

#82
post #28

Earlier quoted context omitted.

What are some superior competing standards, and could they be implemented in a royalty-free way?

If they went extinct they were not superior.

That's just not true. Shoddy builders put quality builders out of business all the time.

Guess it depends on your faith in markets and your definition of superior.

Re: Bob Metcalfe wins Turing Award

#83

Earlier quoted context omitted.

I remember paying about $1000 per port for 100 megabit switches.

Ethernet switches are actually pretty complex things, when you think about it. They have to learn what MAC addresses are behind each port, and build a complex forwarding table and do table lookups in real time. The larger the switch, the more complex it is. Its hard to make it scale. Around the same era, Myrinet switches with higher bandwidth (1.2Gb/s if I remember correctly) and higher density at a fraction of the p…

Very interesting!

Re: Bob Metcalfe wins Turing Award

#84

Earlier quoted context omitted.

HN comment of the year winner right here! Makes you wonder how many other laws are built on nothing. If there's one thing I leaned doing a Ph.D. is if you dig deep enough, you find many foundational laws of nature rely on some necessary assumption that, if proven incorrect, would topple the whole thing

It's worth mentioning Moore's Law, which was actually a short term prediction, arguably turned into a business goal. The "law" states that the number of transistors in integrated circuits (like CPUs) will be doubled every two years (or 18 months by some variations). It wasn't entirely made up, as it was mostly based on advances in manufacturing technology, but it was a prediction made in 1965 that was supposed to hol…

I think it technically kept going into the early 2010s due to additional advancements and technically it hasn’t yet stopped but people are generally skeptical that TSMC and Samsung can keep this party going (a party that seems to have stopped for Intel itself apparently).

Dennard scaling though did end in the mid 00s and this impacted Koomey’s law which talks about performance/watt and saw a similar petering out.

Apparently the bound at even a conservative rate puts the thermodynamic doubling limit at 2080. After that we’ll have to really hope smart people have figured out how to make reversible computing a thing.

Re: Bob Metcalfe wins Turing Award

#86
post #4

Well deserved. I remember dealing with a whole raft of other networking technologies and Ethernet stood head-and-shoulders above anything else available at the time. One thing that is not well appreciated today is how power efficient Ethernet was, even on launch in the coax era. Other network technologies (Token Ring as embodied by IBMs network cards, for instance) consumed power like there was no tomorrow. Leading t…

Sure, years ago. But today Ethernet is just as scammy as everyone else, we've been stuck at 1 Gbps on consumer grade hardware for more than 15 years. There are claims (unverified ofc) about their executives boasting about their stupid margins. 1 Gb switch is like 10-20 euros meanwhile 2.5 Gbps is like over 100...

People buy ethernet for reliable connection and reliable latency (no package drops), and to get 1Gbps. Few consumers have need for more, since internet speeds also rarely exceed 1Gbps.

Sure, anyone with a NAS might like more, but that's a tiny market. And tiny markets lack economy of scale, causing prices to be high.

Re: Bob Metcalfe wins Turing Award

#87
post #67

Earlier quoted context omitted.

The fact that it allowed for all kinds of topologies, and that it served as a bus (shared medium, hence the name 'Ether') rather than a point-to-point link is what I think made the biggest difference. Of course now that we all use switched links they are point-to-point again but an ethernet 'hub' gave you the same effect as a bus with all devices seeing all of the traffic. This made efficient broadcast protocols poss…

And it was sniffing heaven. Only paralleled by the brief period of nobody using any serious encryption on their wifi.

Where "brief" was about 10 years, which at the time was about 25% of all time that networks were common.

Re: Bob Metcalfe wins Turing Award

#88
post #4

Well deserved. I remember dealing with a whole raft of other networking technologies and Ethernet stood head-and-shoulders above anything else available at the time. One thing that is not well appreciated today is how power efficient Ethernet was, even on launch in the coax era. Other network technologies (Token Ring as embodied by IBMs network cards, for instance) consumed power like there was no tomorrow. Leading t…

Sure, years ago. But today Ethernet is just as scammy as everyone else, we've been stuck at 1 Gbps on consumer grade hardware for more than 15 years. There are claims (unverified ofc) about their executives boasting about their stupid margins. 1 Gb switch is like 10-20 euros meanwhile 2.5 Gbps is like over 100...

2.5Gb is downshifted 10Gb with the same line coding, just with 1/4 the symbol rate. This means that it inherits all the complexities of 10GbE, while tolerating cheaper connectors and cables. 10GbE uses DSQ128 PAM-16 at 800Msym/s. 2.5G just does quarter-rate at 200Msym/s.

1000BaseT uses trellis coded PAM-5, a significantly less complex modulation.

When one factors in the complexity of the line code and all equalisation and other processing in the analog frontend things get expensive. Copper 10Gb interfaces run very hot for a reason. It takes quite a bit of signal processing and tricks to push 10Gb over copper, at least for any significant distances.

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