Comment by Sporktacular | Hacker News Reader

Comment by Sporktacular | Hacker News Reader

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Ethernet was always inefficient, with a crazy amount of unused legacy space reserved in an unnecessarily large header. CSMA/CD for contention was one of the ugliest medium access solutions imaginable. The coax implementation needing termination plugs was also ugly. Its advantage was cost, having had no license fees, making it suited to consumer/commercial applications driving economies of scale. It's the VHS of datacomms.

It's evolved, thankfully, but it remains an ugly, inefficient standard that only has life because of its legacy. And it's been increasingly jimmied into professional, carrier applications for which it was never intended and where far superior, though more expensive solutions already existed.

That's not to say its creators don't deserve credit. It did its job well enough for its early days. But that's why this award comes too late. Because now Ethernet is the bloated, inelegant dinosaur we've built an ecosystem around, but to admire it is to forget the competitors it drove to extinction along the way.

It was a lot less ugly than whatever else passed for networking standards at the physical level in those days.

Arcnet, Twinax, Token Ring and so on, I've probably used them all, and at scale. Compared to Ethernet they all sucked, besides being proprietary they were slow, prone to breaking in very complex to troubleshoot ways (though ethernet had its own interesting failure modes in practice it was far more reliable), and some used tons of power which made them unusable for quite a few applications. On top of that it was way cheaper and carried broad support from different vendors, which enabled competition and helped to improve it and keep prices low.

Oh good heavens. Arcnet! When I first learned about writing Linux device drivers, it was trying to get a decent driver for some Arcnet cards that the company I worked at as using in some client installations. Can't remember exactly why we never completed it (well, yea I do. Ethernet worked better, a lot better) but since we never "released the product" they never let us send in the driver we did write to the kernel mailing list. That was in the kernel 1.x days.

Now, I feel old. Time for a nap.

> Now, I feel old. Time for a nap.

Join the club...

And it all seems like yesterday.

Ethernet evolved in backward compatible way for more than 30 years. If we would design a new standard from scratch to fit the same use cases we in theory can learn from the experience and improve things but at the same it would be hard to resist a temptation to make it future-proof by adding a lot of things just in case and this new standard likely will be even more wasteful. And having opportunity doesn't mean it will be used. I often see new design make mistakes avoided in older designs because people have limited time to learn and body of knowledge is too large to always successfully learn from the past.

Also hardware is not like software where you can rewrite a site using a JS framework of the day every few years. Compatibility is really important.

You could not be more wrong! Efficiency and overhead are measured as a percent of frame size and 128-byte packets (X.25) or 48-byte frames (Atm) are abortions. 1500 bytes at the outset and the overhead is < 1% and < 0.2% with jumbograms (8kB). Every 802.11 standard is a superset of Ethernet and that makes DIX Ethernet the most scalable network protocol of all time!

Do you mean subset? It was first standardized as 802.3. Contention under CSMA/CD meant it was not scalable - as in it became inefficient as the segment grew. But you're right and I stand corrected in sense of the header/frame length ratio. I'd edit that first sentence if I still could.

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

The point was more about competing technical choices made by designers, rather than the choice of standards made by consumers. For example TDMA can be arguably more scalable, bandwidth and energy efficient than CSMA/CD and can give consistent PL, PD and PDV, so might have even allowed early business grade voice. Variable header sizes would have allowed efficient use over bandwidth constrained media like radio. But the low cost and fast success of Ethernet formed a barrier to entry for competing LAN standards, where those arguably better technical choices may have found a footing.

They eventually found application in other non-LAN standards, so guess royalties weren't an issue.

None of those things could be implemented in the 1970 or 1980s at reasonable cost so they're not actually solutions at all.

Hell even making Ethernet fully switched didn't really happen until the 1990s thanks to Moore's law making the ASICs cheap enough.

Without mass adoption there's no reason to invest. Look at Token Ring, Ethernet's only real competitor at scale: it quickly started to lag behind. Ethernet shipped 100Mbps several years before Token Ring. The 1Gbps Token Ring standard was never put to hardware.

TDMA is an extension of TDM, which goes back to the 60's. Synchronization was already solved. Variable header size could be implemented with the same preamble concept already used by Ethernet, but used to indicate the end of the header. These were not hard problems. The technology existed, the affordability would have largely depended on adoption, so it's hard to say.

We'll have to agree to disagree. Obviously TDM was known but implementing it for ethernet at a reasonable cost was just not an option at the time (in my opinion).

TDMA needs time synchronization and thus becomes more complex.

Even in telecoms the packet switched connections are quickly replacing synchronous time division connections.

The recent-ish 10base-t1 uses something called PLCA instead of CSMA/CD which doesn't require time synchronization, and gives each node in a subnet a dedicated transmission slot.

10Base-T1L is point to point, 10Base-T1S is multidrop, but very limited in nodes and how long the branches/stubs can be.

We'll see how it actually performs in field. Microchip seems to be in the T1S boat and TI+AD in T1L.

If they went extinct they were not superior.

Betamax was superior to VHS, and it went the way of the dinosaur. Sometimes better means more expensive, and that's not always the popular choice. It wasn't the better survivor, but it was the better format. First to market, higher res, smaller tape, longer life, still lost. But don't take my word for it. https://kodakdigitizing.com/blogs/news/what-is-the-differenc...

Superior includes cost, and even things like number of suppliers.

the best tech doesn't always win, and in fact the "best" tech is typically promoted by people who focus more on the tech and less on go-to-market and competitive strategy. And thus, the "best" tech often loses to the tech that (for example) is better packaged or promoted.

Python is a nice example: inelegant language with many deep flaws, but easy syntax and "batteries included" won the day.

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.

What would you have used (prior to affordable switches) instead of CSMA/CD?

There were a number of ring-based technologies such as Cambridge Ring that even predate Ethernet: https://en.wikipedia.org/wiki/Cambridge_Ring_(computer_netwo...

The main reason Ethernet won, I think, is that it was really easy to deploy incrementally. It was much more plug-and-play than anything else at the time.

My memory is that every ring topology had pretty nasty failure characteristics around "a single misbehaving/failing client."

Which Ethernet has too, but can generally tolerate a much higher level of imperfect reality, while still providing degraded service.

Before you could get plentiful high-quality NICs and cabling, graceful degradation was a killer feature.

You forgot to put on your ATM cap :)

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