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Re: Best utilizing fat long pipes and large file transfer

  • From: Glen Turner
  • Date: Sun Jun 15 22:47:50 2008
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Robert E. Seastrom wrote: 
As a user of hpn-ssh for years, I have to wonder if there is any
reason (aside from the sheer cussedness for which Theo is infamous)
that the window improvements at least from hpn-ssh haven't been
backported into mainline openssh?  I suppose there might be
portability concerns with the multithreaded ciphers, and there's
certainly a good argument for not supporting NONE as a cipher type out
of the box without a recompile, but there's not much excuse for the
fixed size tiny buffers - I mean, it's 2008 already...


Fedora 8 and 9 and Ubuntu 8.04 include the upstream OpenSSH which include
large window patches.  OpenSSH 4.7 ChangeLog contains:

Other changes, new functionality and fixes in this release:
... 
 * The SSH channel window size has been increased, and both ssh(1)
   sshd(8) now send window updates more aggressively. These improves
   performance on high-BDP (Bandwidth Delay Product) networks.

Cheers, Glen

--
 Glen Turner