Re: HTML Streaming

Peter Flynn (pflynn@imbolc.ucc.ie)
28 Aug 1997 22:10:37 +0100 

Date: 28 Aug 1997 22:10:37 +0100
From: Peter Flynn <pflynn@imbolc.ucc.ie>
In-reply-to: <970827192904_1487924785@emout19.mail.aol.com> (Albertfine@aol.com)
To: Albertfine@aol.com
Cc: www-html@w3.org
Message-id: <199708282110.WAA09788@imbolc.ucc.ie>
Subject: Re: HTML Streaming

Albert Fine writes:
   I think I see a flame war simmering so let me make a few things
   clear. I don't work for Double Click :) I am a computer
   consultant. I have taken classes on HTML and I have reviewed the
   XML and HTML 4.0 specifications. I am sure everyone here knows
   something about HTML. My ideas are very early in development. HTML
   streaming basically; organizes the tags in a HTML document to send
   what is displayed first. Tags that are not displayed such as
   keywords, signatures etc. would be added at the end of the file.

OK, there's no reason why you shouldn't rewrite the HTML DTD to do
this. But it wouldn't then be HTML...but it might be called SHTML
(Streaming HTML).

BTW they're not called tags: they're called elements. Tags are the
things that mark the start and end of elements.

   file. These protocols would probably be used by HTML editors. HTML
   streaming also involves two tags; the events tag and the stream
   tag. The event tag would list all the tags in the HTML file with
   rough descriptions so the browser knows what to expect. The stream

But the DTD already does this, and software already exists to handle
it: why would you want a separate file/stream? 

   tag would tell the browser you can display this now, it will not be
   changed. For example, someone mentioned the problem with loading
   tables. The HTML editor could calculate the impact of size elements
   in the table tag. It would add a stream tag to points in the table.
   The stream tag would tell the browser to display the unfinished
   table knowing that it will not be changed. Or the HTML editor could

This already exists in some HTML DTDs: it's called COLSPEC or COL.
It was designed specifically for what you describe.

   add a rough description of the table to the events tag. You would
   have the table streamed without major changes to the table tag or
   using a proprietary tag. I don't think tables are the last or only
   example of the need for HTML streaming. I don't think the speed at
   which a page loads while downloading is the biggest problem in the
   world but I do think we should take the initiative. Please review
   all the articles in the thread;
   http://lists.w3.org/Archives/Public/www-html/1997Aug/thread.html#290

I'm still not clear what needs to be done to enable streaming that
cannot already be done with existing definitions. I don't think that
removing the header to the end of the file is productive merely on the
grounds that the information in it is not displayed: there are other
reasons for things to occur where they do -- indexing engines for
example want to find the list of keywords near the top of the file, to
minimize the volume of data they read before getting to them. I think
you'll find that the organization of HTML -- however deficient in
other areas -- was done for good reasons, and I'd hesitate to undo it
unless for equally good ones.

It does strike me that you have a very good potential application, but
that it could be implemented much more easily by using all the
existing facilities first, before you add new ones or change things
around. 

///Peter