- From: <lee@sq.com>
- Date: Sat, 19 Apr 97 16:51:48 EDT
- To: w3c-sgml-wg@w3.org
Terry Allen <tallen@sonic.net> wrote: > you need to step back and define an overall architecture for pointing > at everything you might want to point at, packaging it together, and > delivering it without ambiguity (avoiding the Panorama disease). We prefer not to refer to Panorama as a disease, actually. I think this is a little excessive. > http://www.wco.com/~books/draft.5feb97.txt If that proposal were used for HTML, browsers like Netscape and Opera would be noticably slower. I don't think anything that is demonstrably worse than current practice should be adopted, although it may be considered where it has merit. The SGML Open multipart-related draft was done so that SGML could be exchanged by e-mail. It doesn't work well for the web because it precludes (or considerably conplicates) parallel fetching. For example, once I have seen the start of an XML document, up to the end of the DOCTYPE section, I know whether I have to fetch a DTD, and, if so, how. So I might as well start fetching it immediately without waiting for the rest of the document. Same for style sheets (I hope). Since XML now has PUBLIC Identifiers, I will want to do my DNS queries on those (the resolution method I've chosen [1]) as soon as possible, since it can take several seconds. So I want to get references to all included files as soon as possible. Hence, I want to get, in this order: * the start of the document * all external DTD fragments * URLs of any included images, so I can start fetching them * the text of the document With HTTP NG, this can all be done over a single HTTP connection, if everything comes from the same server. With HTTP 1.1, I can fetch multiple things in sequence cheaply, so I can keep just a few connections and multiplex over them myself if I want in my client. None of this is to say that Terry's Unoptimized SGML-Bundle Relations Schema does not have merit for other uses, by the way, than for interactive Internet delivery of SGML. Lee
Received on Saturday, 19 April 1997 16:51:53 UTC