just saw this recommendation on yt 1 minute ago.. released 3 hours ago by The Serial Port...small world.
That doesn't make any sense, this video was published days ago. I watched it then.
The comment you replied to was published 4 days ago
The history of twisted-pair Ethernet [video]
11–20 of 27 posts
Re: The history of twisted-pair Ethernet [video]
#12Earlier quoted context omitted.
That doesn't make any sense, this video was published days ago. I watched it then.
The comment you replied to was published 4 days ago
It says "9 hours ago" to me. Is this one of those situations where HN reposted the post and the comments as well? I wish the date and time were kept accurate instead of being confusingly changed.
Re: The history of twisted-pair Ethernet [video]
#13Earlier quoted context omitted.
The comment you replied to was published 4 days ago
It says "9 hours ago" to me. Is this one of those situations where HN reposted the post and the comments as well? I wish the date and time were kept accurate instead of being confusingly changed.
Huh, for me in Hacki on Android both the original comment and the root post say "4 days ago"
Re: The history of twisted-pair Ethernet [video]
#14Earlier quoted context omitted.
The comment you replied to was published 4 days ago
It says "9 hours ago" to me. Is this one of those situations where HN reposted the post and the comments as well? I wish the date and time were kept accurate instead of being confusingly changed.
Yes it is. https://web.archive.org/web/20241226052659/https://news.ycom... (Archived page is from 2024-12-26, and you can mouse over the "# minutes ago" links in the title and comment to confirm.)
Re: The history of twisted-pair Ethernet [video]
#15just saw this recommendation on yt 1 minute ago.. released 3 hours ago by The Serial Port...small world.
That doesn't make any sense, this video was published days ago. I watched it then.
Unfortunately, when submissions get put back into a "2nd chance queue", the "elapsed time calc" is modified to be more recent -- which causes confusion. The thread that's given "new life" for more engagement now has a mix of real and fake "x hours ago".
If you're on a desktop browser instead of a smartphone, you can use F12 Dev Tools to inspect the parent post[1] elements to see that the original timestamp is still there as "2024-12-26T05:23:25 1735190605" ... which is actually about 4 days ago.
Some search engines (bing) still has a cache of this thread we're in from 4 days ago.
https://imgur.com/a/example-hacker-news-thread-put-back-into...
If one were to click on that 4 day old thread, you come here where all the comments are "x hours ago". It's confusing.
Re: The history of twisted-pair Ethernet [video]
#16My history with networking:
- late 70s, rs232 terminals. well, it kind of worked. i spent a lot of time under the desk
- early 80s, frozen hose ethernet - i remember not being able to get a sun workstation to sit on the desk because the cable lifted it off too much
- late 80s coax ethernet all sorts of termination and other problems
- 90s twisted pair and hubs - things started working as they should.
- a bit later cheap switches came along, but still lots of wires at the desk
- now, wireless bliss.
- don't talk to me about token ring.
But of course I don't do this stuff any more.
Re: The history of twisted-pair Ethernet [video]
#17[dead]
Re: The history of twisted-pair Ethernet [video]
#18Dammit, the video doesn’t explain why we have 4 twisted pairs in our cables instead of just 2! One for Rx, one for Tx, but then why did they keep the other two? Surely they didn’t have 4 dead wires just because of legacy? So why the additional pairs, what were they used for?
Re: The history of twisted-pair Ethernet [video]
#19I found the reddit thread referenced in the video and left comments - On the original ethernet being a mistake - "I have another perspective on this - the bus concept at its roots dates to 1974/75 - a machine that could function as a hub in 1975 or even in 1979 would have potentially been as large and costly as the mini-computers Ethernet was intended to interconnect. A switch at that time would have been extraordina…
Also (as you know), twisted-pair Ethernet with a hub (let alone that STARNET daisy-chain thingy!) just isn't that different from coax Ethernet. Electrically it's largely shared-medium, half-duplex bus Ethernet wearing a mechanical hub-and-spoke disguise, and the hub is by definition just a multiport repeater. It's only when the hub is replaced by a multiport switch that shared-medium Ethernet is decisively left behind.
Which brings me to one thing that puzzled me about the video. In the part starting from 10:37 https://youtu.be/f8PP5IHsL8Y?t=637 it describes STARLAN as specifying two pairs of wires, one for transmit and one for receive. But naturally you can't really have full duplex without a switch at the other end of the wire; and yet the STARLINK "Network Extension Unit" is described as a hub (and indeed it seems that the first Ethernet switches/multiport bridges didn't ship until 1989-1990). So when at 12:10 https://youtu.be/f8PP5IHsL8Y?t=730 the video seems to suggest that STARLINK being half-duplex was a step back from the original plan, I don't see how that can be the case: I assume that first-generation STARLINK was never intended to provide full duplex, and the two pairs of wires were just reserved for future upgrades. That seems compatible with what Richard Bennett says from 12:29 . That's still interesting, though, because it suggests that the STARLINK contributors must have had switches in mind back in 1983.
Re: The history of twisted-pair Ethernet [video]
#20Dammit, the video doesn’t explain why we have 4 twisted pairs in our cables instead of just 2! One for Rx, one for Tx, but then why did they keep the other two? Surely they didn’t have 4 dead wires just because of legacy? So why the additional pairs, what were they used for?
Signal integrity basically. Using more pairs means reducing the bandwidth needed on each pair, thus the cost of the cable.