IPP> ADM - New Pronunciation of IPP? [confusion about 'image/ tiff' IPP document format]

IPP> ADM - New Pronunciation of IPP? [confusion about 'image/ tiff' IPP document format]

IPP> ADM - New Pronunciation of IPP? [confusion about 'image/ tiff' IPP document format]

Hastings, Tom N hastings at cp10.es.xerox.com
Thu May 13 12:42:04 EDT 1999


Unfortunately, the current mechanism in IPP for a Printer to list the
document formats that it supports is to list the MIME types, possibly with
parameters that have been registered with the MIME type.

For the MIME type image/tiff there are only two parameters registered:
faxbw and faxcolor.  There has been debate what the meaning of 'image/tiff'
without any parameters.  Some say that without either parameter the document
format supported is the 1994 TIFF spec that doesn't have tiff/fx (TIFFPLUS).
Some say that in order to indicate that you support tiff/fx, you must add
either the 'faxbw' or the 'faxcolor' parameter.

Here is the Feb 1999 registration.  I don't know whether it has been since
clarified any more.  Until it is, we decided it was best not to mention
'image/tiff' as one of the example mimeMediaType values in IPP Model
document.  We will clarify this as part of QUALDOCS.

   To: IANA at isi.edu

   Subject: Registration of new Application parameter values for
   image/tiff

   MIME media type name: image/tiff

   Optional parameters: Application

   New Value(s): faxbw, faxcolor

   Description of Use:

faxbw - The "faxbw" application parameter is suitable for use by
applications that can process one or more TIFF for facsimile profiles
or subsets used for the encoding of black-and-white facsimile data.
The definition of the use of this value is contained in Section 9 of
this document (TIFFPLUS).
 
Faxcolor - The "faxcolor" application parameter is suitable for use by
applications that can process one or more TIFF for facsimile profiles
or subsets that can be used for the encoding of black and white, AND
color facsimile data. The definition of the use of this value is
contained in Section 9 of this document (TIFFPLUS).

-----Original Message-----
From: harryl at us.ibm.com [mailto:harryl at us.ibm.com]
Sent: Wednesday, May 12, 1999 12:28
To: Larry Masinter
Cc: don at lexmark.com; cmanros at cp10.es.xerox.com; ipp at pwg.org
Subject: RE: IPP> ADM - New Pronunciation of IPP?




I don't think it is necessary to mandate support for a minimum format in ipp
(the standards specification) - but rather in the implementations that want
to
described themselves as "i-fax" capable. IPP already has the ability to
indicate
PDL support. I don't believe there would be anything to prevent indicating
support for TIFF-F or TIFF FX via IPP.

Harry Lewis
IBM Printing Systems
harryl at us.ibm.com



"Larry Masinter" <masinter at parc.xerox.com> on 05/12/99 08:28:03 AM

To:   don at lexmark.com, cmanros at cp10.es.xerox.com
cc:   ipp at pwg.org (bcc: Harry Lewis/Boulder/IBM)
Subject:  RE: IPP> ADM - New Pronunciation of IPP?





I think before you start e-printing or ipping things to each other,
you need to face the small technical details that will
get in the way:

a) document format. Although IPP is a nice interoperable
protocol, one person's IPP server won't necessarily do the
right thing with another person's IPP client's documents
unless there's a little more care played with
printer-formats-supported. I think what you really
need for guaranteed interoperability is:
  1) a minimum format that everyone is guaranteed to understand
     (TIFF profile S, anyone?)
  2) some better way of the sender determining recipient
      capabilities (printer-features using CONNEG syntax, anyone?)

b) sender and recipient identification. Although IPP has some
features that might be used for these, you won't have interoperability
until you standardize on their use. You need:
   1) sender identification. While the 'authentication'
   used for authorization to use the printer might serve
   as an identification, sometimes it doesn't. You need
   to clearly say which parts of IPP are supposed to be
   used for "who is this from", and encourage the use
   of this material on the cover sheet.
   2) recipient identification. Maybe this is the "user name"?
   The problem is that with "printing" the "sender" is usually
   the same as the "recipient". You know, I "print" something
   by "e-print"ing it to myself. But I think IPP has only one
   user field, whereas if you're going to use it for
   communication, you need two.

So, before going off into too many more flights of fancy about
internet printing, could you focus a bit on the issues that
were labelled "IPP2FAX" before?

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







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