[whatwg] Link rot is not dangerous

[Shelley Powers]

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