Subject: Re: IPP> Supported URIs for print-by-reference

From: Larry Masinter <[email-masked]>
Date: Thu, 25 Sep 1997 09:11:42 PDT

I think that putting that IPP servers MUST support "ftp:" is a mistake,
since the "ftp:" URL scheme will probably not progress along standards
track without some serious reengineering, and it isn't clear what it
is that you're expecting the printers to be conformant with. MUST they
also support the ";type=" option in FTP URLs, since that's a Proposed
Standard? MUST they also support ftp://user:@host/ forms? 

Right now, the choice of binary or ascii transfer methods in FTP is
heuristic.

Frankly, you'd be better off requiring support for URIs of type "https",
and also in specifying other attributes of what a printer might do when
retrieving data via http on behalf of another user, e.g., supplying
credentials, the user-agent string, cookies, etc.

Larry
-- 
http://www.parc.xerox.com/masinter

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From: Carl-Uno Manros <[email-masked]>
Date: Thu, 25 Sep 1997 09:55:29 PDT

>Right now, the choice of binary or ascii transfer methods in FTP is

This might be a reason to drop ftp from our mandatory list, but in any case
we cannot always guarantee that a print-by-reference URI will actually work.

>credentials, the user-agent string, cookies, etc.

Sorry, but we have already discovered that we cannot do print-by-reference
with any of the existing security mechanisms, so forget "https".  We have
enough problems with wanting to reference security work that is not yet on
the standards track. 

>Larry
Carl-Uno Manros
Principal Engineer - Advanced Printing Standards - Xerox Corporation
701 S. Aviation Blvd., El Segundo, CA, M/S: ESAE-231
Phone +1-310-333 8273, Fax +1-310-333 5514
Email: [email-masked]