[Opensim-dev] Global identifiers

[Serendipity Seraph]

 On 8/29/10 11:45 AM, Dahlia Trimble wrote:
> This looks to me to be an attempt to provide local caching of relevant
> information for reducing lookup requirements and seems a usable
> approach as long as the extra data is known to be non-authoritative.
> It does bring a implementation-specific form into something that has
> potential to becoming a standard of sorts and that may be a concern.
> It does not appear to address the problem of fly-by-night service
> providers or those who may try to profit excessively from a position
> of providing an authority. Personally I don't like the idea of having
> a paid subscription service having any control over my ability to surf
> the hypergrid, and as such I''d prefer to see the UUID portion be the
> authoritative lookup key and the lookup domain portion be considered a
> suggestion at best. UUIDs by design have sufficient variability where
> collisions are highly unlikely so I don't see collisions as being an
> issue even if they are independently generated by independent providers.
IMHO, all references should always be to a key type that is by
definition not prone to collision.  UUIDs were designed for this
purpose.  That does leave what user name and whatever a UUID maps to. 
Caching the mapping with something like memcache should be possible.  
Stuffing possibly mutable [and/or collision prone] data  into URIs
(effectively pointers) or other identifiers is a bad idea.  Identifiers
are not supposed to be meaning or semantic bearing. 

- s