Subject: RE: RFC 2534 list of ua-media and paper-size values

From: Graham Klyne <[email-masked]>
Date: Wed, 20 Oct 1999 10:59:10 +0100

At 18:31 19/10/99 -0700, Herriot, Robert wrote:
>It doesn't seem reasonable to merge the values of HTML "media" and IPP
>"media". The former describes media in a large sense. The latter desribes
>media in the context of a printer.
>
>I agree that all of the print related values of RFC 2534 should be
>deprecated and that the word "print" should be used instead as a value of
>"media"  It would be reasonable to add a new attribute "print-media" which
>contains the values of the IPP "media" attribute.

Robert,

This would seem a reasonable approach if one takes a view that it is always
known a priori in what kind of environment a resource will be used.  But I
do not share that view.

The original CONNEG work was motivated in part by a desire to have a way to
express common media features that could used across a range of transfer
protocol environments.  This in turn, I belive, creates an environment in
which it becomes easier to build integrated services that use a variety of
protocols;  e.g. web servers for e-mail collection, IPP for quality
document transfer, e-mail for fax transmission, etc.

The model that we have evolved for Internet fax, and which I believe could
usefully be employed in other scenarios, is to use common vocabulary for
features that are common across a variety of service environments (e.g. per
RFC 2534), and to develop a more specialized vocabulary for features that
more more specific to the fax environment.  This approach is realized by
having the generic feature tags be very broadly defined, and using
specialized feature tags to refine them (in the sense of constraining
rather than revising).

In summary, I would suggest resisting a divergence of vocabulary for
features that are common across a range of services.

#g

------------
Graham Klyne
([email-masked])

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From: Al Gilman <[email-masked]>
Date: Wed, 20 Oct 1999 08:44:05 -0500

>features that are common across a range of services.

The generic and specific vocabulary entries will compete for usage.  But
having the generic ones there and knowing that the specific ones conform to
generic supercategories is beneficial for access by people with disabilities.

One interesting example is that the "projection" context-of-use class in
the CSS writeup, at least, includes both print and LCD options for getting
from softcopy to the group-visible display.

Al

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From: Chris Lilley <[email-masked]>
Date: Thu, 21 Oct 1999 03:17:05 +0200

> from softcopy to the group-visible display.

I don't think that projection is necessarily a print-related media. It
is intended for projection from laptops, a situation that W3C staff are
intimately familiar with ;-)

--
Chris