Hello Karl,<br><br><div><span class="gmail_quote">On 2/16/06, <b class="gmail_sendername">Karl A. Magdsick</b> <<a href="mailto:kmagdsick@limewire.com">kmagdsick@limewire.com</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Charles Iliya Krempeaux wrote:<br>[snip]<br><br>>I suppose if the "Link" header is being used to return information,<br>>this could be generalized to make this "conditional get" be a way to<br>>probe for "Link" data.
<br>><br>>So, instead of using "X-If-No-Alternate" it could be "X-If-No-Link"<br>>(and then specify what relation or other meta data you want).<br>><br>>For example, I could get a blogs RSS feed with:
<br>><br>> X-If-No-Link: rel="alternate"; type="application/rss+xml"<br>><br>>Although the exact notation may need to be different since using the<br>><br>><br>Why add an extra header in this case? It would be less intrusive to the
<br>webserver<br>code if the client issues a HEAD request and checks for Link headers, rather<br>than add a completely new X-If-No-Link header.<br><br></blockquote></div>There's 2 reasons.<br><br>The first is that it would be for the same reason that we have the other "conditional gets"... speed. The time it takes to "create" and "tear down" a TCP connection is significant. And, from a users point of view, will impact usability, in that it will make things seem slower (if we have to create 2 separate TCP connections for every request we want to do).
<br><br>If you could assume that ever server always had a "persistent connection" (or "keep alive" connection, or whatever you want to call them), then this wouldn't be an issue. But, you can't make that assumption. So that's why "conditional gets" are used.
<br><br>And the second (and probably more important reason) is that I'm making the assumption that the server would NOT always give all these Link headers. (And that some kind of "probing request", like via "X-If-No-Link", is required.)
<br><br><br>Comments? Suggestions?<br><br clear="all">See ya<br><br>-- <br> Charles Iliya Krempeaux, B.Sc.<br><br> charles @ <a href="http://reptile.ca">reptile.ca</a><br> supercanadian @ <a href="http://gmail.com">
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