- From: Kristof Zelechovski <giecrilj@stegny.2a.pl>
- Date: Fri, 15 May 2009 21:04:27 +0200
Serving the RDFa vocabulary from the own domain is not always possible, e.g. when a reader of a Web site is encouraged to post a comment to the page she reads and her comment contains semantic annotations. The probability of a URL becoming unavailable is much greater than that of both mirrored drives wearing out at the same time. (data mirroring does not claim it protects from fire, water, high voltage, magnetic storms, earthquakes and the like; it only protects you from natural wear.) The probability of ultimately losing data stored in one copy is 1; the probability of a URL going down is close to 1. So, RAID works in most cases, CURIE URL do not (ultimately) work in most cases. Disappearing CSS is not a problem for HTML because CSS does not affect the meaning of the page. Disappearing scripts are a problem for HTML but they are not a problem for HTML *data*. In other words, script-generated content is not guaranteed to survive, and there is nothing we can do about that except for a warning. Such content cannot be HTML-validated either. In general, scripts are best used (and intended) for behavior, not for creating content. External SVG files do not describe existing content, they *are* (embedded) content. If a HTML file disappears, it becomes unreadable as well, but that problem obviously cannot be solved from within HTML :-) "HTML should be readable in 1000 years from now" was an attempt to visualize the intention of persistence. It should not be understood as "best before", of course. If the author chooses to create a redirect to a well-known vocabulary using a dependent vocabulary stored at his own site in order to prevent link rot, tools that recognize vocabulary URL without reading the corresponding resources will be unable to recognize the author's intent, and for the tools that do read the original vocabulary will still be unavailable, so this method causes more problems than it solves. Cheers, Chris
Received on Friday, 15 May 2009 12:04:27 UTC