- From: Shelley Powers <shelleyp@burningbird.net>
- Date: Fri, 15 May 2009 14:57:17 -0500
Philip Taylor wrote: > On Fri, May 15, 2009 at 6:25 PM, Shelley Powers > <shelleyp at burningbird.net> wrote: > >> The most important point to take from all of this, though, is that link rot >> within the RDF world is an extremely rare and unlikely occurrence. >> > > That seems to be untrue in practice - see > http://philip.html5.org/data/rdf-namespace-status.txt > > The source data is the list of common RDF namespace URIs at > http://ebiquity.umbc.edu/resource/html/id/196/Most-common-RDF-namespaces > from three years ago. Out of those 284: > * 56 are 404s. (Of those, 37 end with '#', so that URI itself really > ought to exist. In the other cases, it'd be possible that only the > prefix+suffix URIs are meant to exist. Some of the cases are just > typos, but I'm not sure how many.) > * 2 are Forbidden. (Of those, 1 looks like a typo.) > * 2 are Bad Gateway. > * 22 could not connect to the server. (Of those, 2 weren't http:// > URIs, and 1 was a typo. The others represent 13 different domains.) > > (For the URIs which returned Redirect responses, I didn't check what > happens when you request the URI it redirected to, so there may be > more failures.) > > Over a quarter of the most common namespace URIs don't resolve > successfully today, and most of those look like they should have > resolved when they were originally used, so link rot seems to be > common. > > (Major vocabularies like RSS and FOAF are likely to exist for a long > time, but they're the easiest cases to handle - we could just > pre-define the prefixes "rss:" and "foaf:" and have a centralised > database mapping them onto schemas/documentation/etc. It seems to me > that URIs are most valuable to let any tiny group make one for their > rarely-used vocabulary, and be guaranteed no name collisions without > needing to communicate with a centralised registry to ensure > uniqueness; but it's those cases that are most vulnerable to link rot, > and in practice the links appear to fail quite often.) > > (I'm not arguing that link rot is dangerous - just that the numbers > indicate it's a common situation rather than an extremely rare > exception.) > > Philip, I don't think the occurrence of link rot causing problems in the RDF world is all that common, but thanks for looking up this data. Actually I will probably quote your info on my next writing at my weblog. I'd like to be dropped from any additional emails in this thread. After all, I have it on good authority I'm not open for rational discussion. So I'll leave this type of thing to you guys. Thanks Shelley
Received on Friday, 15 May 2009 12:57:17 UTC