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Comment by s-macke | Hacker News Reader

It is not faster in this sense. However, an SSH connection can have multiple substreams, especially for port forwarding. Over a single classical connection, this can lead to head-of-line blocking, where an issue in one stream slows everything down. QUIC/HTTP3 protocol can solve this.

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Does this implementation do that do, or does it just use a single h3 stream?

The answer is yes according to code and documentation [0]:

> The stream multiplexing capabilities of QUIC allow reducing the head-of-line blocking that SSHv2 encounters when multiplexing several SSH channels over the same TCP connection

....

> Each channel runs over a bidirectional HTTP/3 stream and is attached to a single remote terminal session

[0] https://www.ietf.org/archive/id/draft-michel-remote-terminal...

Fun fact: SSH also supports multiple streams. It's called multiplexing.

Multiple streams at the application level, which can be head-of-line blocked due to all being multiplexed on the same transport layer connection.

The former kind of multiplexing addresses functionality, the latter performance.

Doesn't it run over a single TCP connection in all cases, unless you manually launch multiple and manually load-balance your clients across is? As in, it won't/can't open a new TCP connection when you open a new connection in the SOCKS proxy or port forward. They'll all share one head-of-line and block each other

Not that I've ever noticed this being an issue (no matter how much we complain, internet here is pretty decent)

Edit: seeing as someone downvoted your hour-old comment just as I was adding this first reply, I guess maybe they 'voted to disagree'... Would be nice if the person would comment. It wasn't me anyway

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