Namespaces and PURLs

Simon St.Laurent SimonStL at
Thu Jun 4 17:16:37 BST 1998

Although this comes from the XSchema proposal, it's a more general question 
about namespaces.

For the 5/18 draft
>The namespace name, to serve its intended purpose, should have the 
>characteristics of uniqueness and persistence.  It is not a goal that
>it be directly usable for retrieval of a schema (if any exists).

This sounds like I can use a PURL (see for details) as a 
URI in a namespace declaration.  They are unique and persistent, assuming the 
OCLC doesn't disappear any time soon.  They are retrievable, though with a 
hitch - the OCLC sends a redirect to the 'actual' location to which the PURL 
refers.  That location may change, though the PURL doesn't.  (The same holds 
true for domain names, but the mechanisms are more commonly understood and 
implemented at a lower level.)

Does the "it is not a goal" language mean that I can use a PURL, or should I 
stay away from doing so because some applications may be unable to handle an 
attempted resolution of (and redirection from) that URL?  Applications don't 
appear to be prohibited from such retrieval; it's just not a goal that they do 

Several others on the list have commented about possible useful things to put 
at the end of a namespace URI, so I'm a little concerned.

Simon St.Laurent
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