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Comment by throw0101c | Hacker News Reader

> Ethernet used to be a collision domain on coaxial cable, not a switched full-duplex medium on twisted pair.

And it's come back full-circle to (radio) collision domains (à la AlohaNet) with Wifi, which I think the vast majority of people use on a day-to-day basis rather than plugging in.

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The original Ethernet spec uses CSMA/CD[0] 802.11 uses CSMA/CA[1]

[0] https://en.wikipedia.org/wiki/Carrier-sense_multiple_access_... [1] https://en.wikipedia.org/wiki/Carrier-sense_multiple_access_...

> the vast majority of people use on a day-to-day basis rather than plugging in.

For last 100 feet yes, but for the entire rest of the network it's either fiber or copper. Notably, Ethernet framing sometimes with additional encapsulation is used everywhere along the path.

That may have been true in the past, but recently the same principle (using a hybrid) for simultaneous tx/rx on GBE can be employed on a point-to-point radio channel.

https://www.microwaves101.com/encyclopedias/simultaneous-tra...

And in which 802.11 amendment is that in? :)

It's not a standard, it's a technology. 802.3 defines full-duplex (wired) gigabit Ethernet with each end of the peer-to-peer link both transmitting and receiving at the same time over the same wires. Add a similar hybrid to your WiFi PHY and you're done. It does also require MIMO beam forming to cancel the interference from other users on the same WAP.

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