- From: Herriot, Robert <Robert.Herriot@pahv.xerox.com>
- Date: Wed, 10 Jan 2001 19:06:00 -0800
- To: "Thomas D. Hite" <tdhite@yahoo.com>, xml-dist-app@w3.org
I don't think that SOAP solves the problem. The problem, as I understand it, is that the XHTML-Print document needs to be split into several fragments so that binary images can be interspersed between XHTML-Print fragments. The problem is that each XHTML-Print fragment is not well-formed. Only the concatenated contents of all the XHTML-Print fragments is well-formed. I think that such a solution implies new Content-Types and rules for assembling them. > -----Original Message----- > From: Thomas D. Hite [mailto:tdhite@yahoo.com] > Sent: Wednesday, January 10, 2001 9:18 AM > To: xml-dist-app@w3.org > Subject: Re: question about XML protocol requirements > > > > I would appreciate your thoughts on images and XML in a > memory constrained > > environment. > > With the risk of stepping out of bounds (I'm not on this particular > committee) or repeating old posts, I'd like to suggest > something related to > your question. I too spend time with other standards efforts, > some of which > are tightly related to device networking (like printers). > > Your question starts by discussing XHTML-Print, yet asks the > question of XML > in a constrained environment. Rather than cover the former > however, I'd like > to suggest that XML is a very convenient model for > constrained environments. > > Let's just take the SOAP model for discussion purposes. There is no > requirement, in any way shape or form, that an entire print > document pass in > a single SOAP message. If appropriate to the standards body, a > query/response mechanism can (should?) be adopted. Any images > not able to > fit in a single (non-chunked transfer) message would be passed across > multiple messages, either as a link to a potentially chunked > transfer, or as > multiple query/response pairs. The latter, though, would > require yet another > binary transfer protocol of which I'd not be a fan. > > My suggestion here is that while XHTML-Print is interesting > for memory and > CPU rich rendering devices, a SOAP (or XP) query/response > protocol would > seem more interesting as a 'general purpose' model. The > standards bodies I > work with generally have a goal of producing results sooner > rather than > later, which is an agreeable goal, so as yet they, have not > attempted to > construct such a model and have purposely shied away. > > While such a model places more burden on the device > requesting the print (or > any other rendering for that matter - such as streaming > audio/video), we can > be relatively assured that that particular device will not be memory > constrained since it definitely must contain the document in question. > > > Is anyone else looking at this problem? > > The UPnP printing and Technical Committees are both spending > plenty of time > on this issue. > > Tom Hite > > > ----- Original Message ----- > From: "Herriot, Robert" <Robert.Herriot@pahv.xerox.com> > To: <xml-dist-app@w3.org> > Sent: Tuesday, January 09, 2001 3:41 PM > Subject: question about XML protocol requirements > > > > > > I have a question about the work on XML protocol requirements. > > > > I am working with several standards groups that defining > XHTML-Print, > which > > is XHTML-Basic plus a few page related features. > XHTML-Print needs to be > > able to reference non-XML data, such as jpeg images. > > > > Your document states in R700a that ebXML and RosettaNet are > solving the > > problem of binary data in XML and the W3C XML Protocol > Group is not. Those > > groups both solve the binary-data problem with multipart/related. > > > > We have considered a similar solution for XHTML-Print, but > we have one > > additional constraint that is not addressed by the ebXML or > RosettaNet > > solutions. Some printers have only enough memory to hold a > page or two of > a > > document stream. Such a printer must be able to obtain an > image from a > > nearby place in the document stream; it cannot read through > and buffer an > > entire XML document before finding the image. > > > > Is anyone else looking at this problem? > > > > Ideally there should be less than one printed page of XML text data > between > > an image and its reference. In the context of multipart/related This > > constraint seems to imply that: > > > > a) the XML text data must be split into multiple fragments > with one or > more > > images between each XML fragment, > > b) there must be a root object that references all of the > XML fragments > with > > cid's > > c) images must be referenced with cid's within the XML fragments. > > > > The XML-fragment concept may have problems because the XML is not > > well-formed until all fragments are concatenated. > > > > I would appreciate your thoughts on images and XML in a > memory constrained > > environment. > > > > Bob Herriot > > > > > > _________________________________________________________ > Do You Yahoo!? > Get your free @yahoo.com address at http://mail.yahoo.com >
Received on Wednesday, 10 January 2001 22:06:04 UTC