A question on C), I am not sure what you mean by well formed. I assume it
is not well formed in the XML sense. My guess is that it is well formed in
the PWG sense. That only means that the keyword values used are well-known
values. It does not mean that the values are supported by the Printer
instance. Is there any requirement for the schema to restrict the
well-known values to the subset supported by a Printer?
I somewhat disagree with D). I think it is more important to facilitate the
operational use of the PWG schema in product environments. The well-known
values in question are not meant for end-user consumption. Facilitating the
developers can be accomplished through a transformed schema that takes
appinfo and makes them enumerations. The client implementation can localize
or present, in an application specific manner, keywords from appinfo or
We have elements that can be vendor or site extended. Whatever we end up
with I want to insure that Clients are able to discover, via GetAttribute
action or a schema, and send those extended values. The Printer must allow
the application to determine if the attribute/value is supported.
As for B), I misspoke. What I intended to say is "Enable print client
developers to ascertain the supported keywords for an element of a Printer
at runtime" I believe the PWG Semantic Model defines the basic objects,
their attributes, the well-known values for specific attributes and the high
level description of the actions on the objects. We have seen in real world
examples that vendors and site specific extensions and restrictions exist
and are critical to many customer solutions. Static definitions may be
applicable in certain solutions but the majority of solutions require the
ability to determine what attributes and values are supported. Capability
discovery is somewhat related but goes well beyond what attributes/vales are
implemented by a Printer. Our goal should be to make the individual
semantic elements useful for a capabilities solution.
Xerox Architecture Center
Email: PZehler at crt.xerox.com
Voice: (585) 265-8755
FAX: (585) 265-8871
US Mail: Peter Zehler
800 Phillips Rd.
Webster NY, 14580-9701
From: TAYLOR,BOB (HP-Vancouver,ex1) [mailto:robert_b_taylor at hp.com]
Sent: Thursday, September 26, 2002 4:42 PM
To: PWG Semantic Model WG (E-mail)
Subject: RE: SM> Keyword Extension ISSUE 1
C) Allow system entities to use standard XML tools and the PWG (and
potentially other) schemas to determine that a request is well formed
D) Facilitate development around the PWG semantic model by creating
schema structures that expose both objects and values through commonly used
As for B), I'd say the semantic model certainly needs to enable capabilities
to be ascertained, but I'm not honestly sure whether it's in scope for the
SM project to "completely" solve this. It may be sufficient here just to
declare the objects & values in such a way that they can be readily used by
capabilities schemes, and that the "full" capabilities problem will be
solved in forums like PSI & UPDF.
> -----Original Message-----
> From: Zehler, Peter [mailto:PZehler at crt.xerox.com]
> Sent: Thursday, September 26, 2002 5:50 AM
> To: PWG Semantic Model WG (E-mail)
> Subject: SM> Keyword Extension ISSUE 1
>> As stated in the previous mail note "CORRECTED Keyword
> Extension Mechanism
> for schema" sent earlier, I would like to resolve ISSUE 1.
>> ISSUE 1: What requirements do we have to help us close on a solution?
>> It seems to me that the primary objectives are to
> A) Insure that the schema for the print model is easily
> extended. For both vendors and sites. The extensions should
> be allowed at
> both the object and semantic element value levels.
> B) Enable print client developers to ascertain the
> of a print device at runtime.
>> I think I heard a requirement that a client be able to
> determine that a
> request is well formed, in the PWG schema sense, using XML
> tools and the PWG
> schema. Am I hearing that requirement correctly?
>> What do you think the requirements are for selecting a
> solution for schema
>>> Peter Zehler
> Xerox Architecture Center
> Email: PZehler at crt.xerox.com> Voice: (585) 265-8755
> FAX: (585) 265-8871
> US Mail: Peter Zehler
> Xerox Corp.
> 800 Phillips Rd.
> M/S 128-30E
> Webster NY, 14580-9701