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SSH3: Faster and rich secure shell using HTTP/3

(github.com)
532 points tempaccount420 | 1 comments | 27 Sep 25 14:27 UTC | HN request time: 0s | source
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Zambyte ◴[27 Sep 25 15:01 UTC] No.45396281[source]▶
I was skeptical of the claim that it's faster than traditional SSH, but the README specifies that it is faster at establishing a connection, and that active connections are the same speed. That makes a lot of sense and seems like a reasonable claim to make.
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notepad0x90 ◴[27 Sep 25 15:35 UTC] No.45396639[source]▶
Although, dollars-to-donuts my bet is that this tool/protocol is much faster than SSH over high-latency links, simply by virtue of using UDP. Not waiting for ack's before sending more data might be a significant boost for things like scp'ing large files from part of the world to the another.
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1. lxgr ◴[28 Sep 25 07:35 UTC] No.45402450[source]▶
That's not really a common TCP problem. Only when there's something severely weird going on in the return path (e.g. an extremely asymmetric and/or congested return path connection dropping ACKs while the forward path has enough capacity) does the ACK mechanism limit TCP.

Also, HTTP/3 must obviously also be using some kind of acknowledgements, since for fairness reasons alone it must be implementing some congestion control mechanism, and I can't think of one that gets by entirely without positive acknowledgements.

It could well be more efficient than TCP's default "ack every other segment", though. (This helps in the type of connection mentioned above; as far as I know, some DOCSIS modems do this via a mechanism called "ack compression", since TCP is generally tolerant of losing some ACKs.)

In a sense, the win of QUIC/HTTP/3 in this sense isn’t that it’s not TCP (it actually provides all the components of TCP per stream!); it’s rather that the application layer can “provide its own TCP”, which might well be more modern than the operating system’s.