UDP for data?

David Newall openssh at davidnewall.com
Thu Jul 12 11:58:41 AEST 2018

Hi Stef,

On 11/07/18 21:30, Stef Bon wrote:
> I'm very interested in making SSH use UDP for large data chunks.

You forgot to add, "large data chunks, that you don't mind going 
missing, and that aren't all that large", because, you know, UDP has no 
delivery guarantee, not even best effort.  If you want to guarantee 
delivery you need the recipient to send an acknowledgement, and you have 
to take care of splitting large chunks into datagram-sized pieces and 
reassembling them at the other end. When you've done all of that, you 
might as well have used TCP in the first place.

I remember, when Sun first released NFS they used UDP for transport 
because "performance", and then, not so very long later, had to 
implement TCP transport because "reliability".

It's really not my place to say whether your request will ever be 
accepted, but why not try implementing it, create a  patch, and see?  At 
the very least you'll have something that works for you, even if, (as I 
predict), it is rejected for the baseline.


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