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Date: Fri, 29 Aug 1997 19:21:59 +0200 (MET DST)
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From: Eivind Eklund <perhaps@yes.no>
To: Nate Williams <nate@mt.sri.com>
CC: hackers@FreeBSD.ORG
In-reply-to: Nate Williams's message of Wed, 27 Aug 1997 16:34:07 -0600 (MDT)
Subject: Re: FTP protocol questions (non-passive mode)
References: <199708272234.QAA02520@rocky.mt.sri.com>
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> 
> Can anyone explain to me the FTP 'Data' channel protocol?
> 
> As I understand it, the client creates a socket, and the server binds to
> it, and then the 'DATA' is sent to it.  How does the server know which
> port to bind on the client?  Is there something obvious I don't
> understand as to why they couldn't use the original 'channel'?

It was simpler to design this way - if the data-channel fall, you
still have the control-connection, and it is easier to debug - one
pure text channel.

And FTP is _old_ - it was created in the 70s (the first FTP RFC was
RFC 114 from early 1971).

Eivind.