On Wed, 7 Nov 2007, Patrick Monnerat wrote:

> SO_KEEPALIVE (associated with keep-alive timeout adjustments in the firewall
> and/or client OS) may create transparent activity on the control connection
> without disturbing the FTP protocol itself.

Yes, assuming you can make it send keepalive packets more often than the
timeout time is set to in the firewall. If I recall things correctly,
SO_KEEPALIVE default is something like two hours and I believe there are
operating systems on which changing that time is hard.

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