You actually can connect two machines via USB-C (USB4 / Thunderbolt) and you get a network connection.

You only get Link-Local addresses by default, which I recall as somewhat annoying if you want to use SSH or whatever, but if you have something that does network discovery it should probably work pretty seamlessly.

See https://christian.kellner.me/2018/05/24/thunderbolt-networki... or https://superuser.com/a/1784608

▲ userbinator 6 days ago | parent | next [-]

You only get Link-Local addresses by default

The same thing happens with two machines connected via an Ethernet cable, which appears to be what this USB4 network feature does - an Ethernet NIC to software, but with different lower layer protocols.

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dwattttt 6 days ago | parent [-]

Crossover cables, get'cher crossover cables here!

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deathanatos 5 days ago | parent [-]

AIUI, most NICs these days do what is called "auto-crossover"; i.e., they'll detect the situation and just do the "crossover" in the NIC itself. A normal cable works.

	▲	fodkodrasz 5 days ago \| parent [-]
		Yes, the name is Auto MDI-X and is standard since on-board 1Gbps Ethernet NICs became the norm. https://en.wikipedia.org/wiki/Medium-dependent_interface#Aut...

▲ Dagger2 4 days ago | parent | prev | next [-]

ssh is fine:

  ssh fe80::2%eth0

where fe80::2 is the peer's address, and eth0 is the local name of the interface they're on.

Unfortunately browsers have decided that link-local is pointless and refuse to support it, so HTTP is much more difficult.

▲ grishka 6 days ago | parent | prev [-]

Non-USB-shaped older Thunderbolt, down to version 1, can do this too, iirc. But you do need the expensive and somewhat rare cable.