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Comment by dylan604 | Hacker News Reader

>edit: Gah! you don't even have to do that just flip the flipping wires)

Isn't that essentially what all ethernet cables do? it's not like this something never done before.

Ethernet hardware now has auto-crossover. However, that hasn't always been the case. There was a good decade in the 90's where you needed a special cable wiring if you wanted to connect two computers vs a computer to a switch.

Hah! I recently had to put ends on a Cat 6 cable for weird reasons, and spent a few minutes deciding if it needed to be crossover or not.

The worst is trying to repair one end of an existing cable and having to think really hard about whether to use A or B wiring.

sometimes, it's easier to replace both ends. or replace the same end, twice

Random anecdote: I worked at a company with an on-prem server room and the building got struck by lightning. It fried some servers and quite a few nic cards on employee computers. Our CTO decided since we'd be in the building doing hardware replacements anyway, now was the time to redo our wiring closest as well.

That was my introduction to wiring up CAT-5 cables and rj45 connectors and, with so many to make, I needed a way to remember the wiring diagram without having to read it over and over or use a visual reference. The mnemonic rhythm I used to remember the pattern was "orange/white, orange... green/white, blue... blue/white, green... brown/white, brown". Of course, said out loud, you couldn't tell if it was "orange/white, orange" or "orange, white/orange" and I kept confusing the rest of the team when I'd say it, but it worked for me.

This was circa 2005/2006 and I still say it like that. It just stuck.

Stripey orange

Orange

Stripey green

Blue

Stripey blue

Green

Stripey brown

Brown

Thanks for the memories!

I once used a crossover cable with an old 3Com card and a Linksys switch - whatever it sent down the wires, the Ethernet port on that switch was fried and has never done Tx or Rx since. I bandaged it with electric tape so I don't connect something else, and also in hope it will someday heal.

The 3Com card was unscathed. In fact, it is probably feeling stronger after that exertion.

Easily going into the early 2000s. I remember trying to setup LAN parties in 2004/2005, where the wrong combination of patch or normal cable with hub/switch/PC made everything a nightmare.

I found a few patch cables mixed in with regular cables. one day, i got so tired of messing with them, i cut the cables and put them in the trash. i could have just trashed, them, but that didn't feel right. i mean, what if someone were to go dumpster diving. the curse would then be on them.

Whenever I have a bum cable and confirm it’s the cable, it gets destroyed. Too many cables have failed to get into the trash or have somehow crawled back out for me to do anything else.

I've certainly more than once outright thrown out items for just falling outside of the return window rather than hand-me-downing them to friends for being so crappy that I didn't want to ever operate them ever again in any context.

The one I remember the most was a Bluetooth speaker that yapped your ear off for a half-minute combined with an obscene amount of jingle beeping at 100% blast and more LEDs than a Christmas tree as a power-on/off procedure back when they were novel items.

Uh? They're trivial to tell apart, just put the RJ45 jacks side by side and look at the colors of the wires going in?

Same sequence -> Straight ethernet cable

Same sequence except for 1 swapped pair -> Probably a crossover Ethernet cable

Inverted sequence -> ISDN cable, burn it.

Also (apart from the ISDN cables) - it hasn't mattered for close to quarter of a century, all switches and NICs are auto-MDI-X nowadays, why throw away the stuff.

Now I know I'm old because I just assumed that's how it still was. I'd be like the weird old grandpa at a party talking about a choke or carburetor or a hand crank on a car while all the kids just stare blankly.

When was Auto MDI-X introduced? A quick google failed to get me an answer but I remember USB being available while I still needed a crossover cable to hook up 2 switches.

oh god, I was made to be an idiot when I once told someone they would need a crossover cable to do what they wanted to do a few years ago...

If it makes you feel any better... for some reason there are some currently in production business jets that still require crossover cables for maintenance... so they ARE still required sometimes.

I've also dug further into my parts bin thinking "oh, that yellow cable would've been perfect, but I need a non-crossover cable"... could've used the yellow one instead of digging further. Ah well.

Security through obscurity?

You encounter this in older industrial equipment. Some of the old ethernet chipsets don't support automatically switching the pairs around. It's not really a problem since at least in our local area they need to be installed by licensed cablers who are used to dealing with legacy devices.

Many devices won't get updated until chipsets go EOL or there's some other compelling reason to do so.

Having said that, modern chipsets seem to all support it.

Together with 1Gbit ratification, so ~2000

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