Re: [idn] FTP history

[vint cerf <vinton.g.cerf@wcom.com>]

Dave,

isn't there a distinction to be made between the client and the server here?
The results of the user interaction were exchanges over a TCP connection distinct
from the control connection - that was so even before TCP/IP (with NCP). 
The fact that we used TELNET to drive the FTP control doesn't make the design
any less a protocol. TELNET was a convenient way of implementing the text-based
exchanges - but they had formats that included error numbers as well as text
in the expectation that some implementations of the the client would be machine
driven, I thought. 

The server side plainly had to deal with protocol exchanges between the ftp
data transfer servers on source and sink machines, in addition to the control server
exchanges carried over the TELNET protocol. 

I'm not sure whether this thread/debate is necessarily useful, is it??

vint

At 09:58 AM 5/27/2002 -0700, Dave Crocker wrote:
>At 12:43 PM 5/27/2002 -0400, John C Klensin wrote:
>>  While FTP apparently lends itself to "direct UI", it
>>was never intended that way.
>
>John,
>
>I have a pretty clear recollection that when FTP first came out the folks who wrote the spec honestly expected to be able to sit at a TIP, telnet over to an FTP server, and type commands that would effect file transfers.
>
>I even have a vague recollection that this was used to send data to a printer attached to the TIP on another port.
>
>
>>For example, use of "TYPE ASCII" transfers requires translation
>>between the character set of the sender and network ASCII and
>>translation by the receiver from network ASCII to local
>>character set and formats.
>
>Not if the receiver can process network ASCII directly, as some did.
>
>
>>  Even when those hosts use ASCII, the
>>translations must accomodate, e.g., conversion of end of line
>>conventions.
>
>Not if they supported CRLF directly, as some did.  In fact, that was why CRLF was chosen and end of line, rather than a single character.  A single character would have made lexical analysis notably simpler.
>
>
>>But the protocol is no more designed as a "direct UI" than SMTP
>
>SMTP came around 10 years later.
>
>However, the original MAIL command in FTP was explicitly intended to permit direct typing over a telnet connection.  And it was in fact used that way.  (That was why there was a distinction between MAIL and MLFL which did the data transfer over a separate FTP data connection.)
>
>d/
>
>----------
>Dave Crocker <mailto:dave@tribalwise.com>
>TribalWise, Inc. <http://www.tribalwise.com>
>tel +1.408.246.8253; fax +1.408.850.1850
>