[Opensim-users] Opensim nooby question on UUIDs

[Dahlia Trimble]

UUIDs can be temporary or permanent depending on what they are used for. In
general they are used wherever a unique key is needed for accessing some
other data. Assets such as textures or notecards are assigned permanent
UUIDs, and temporary assets such as avatar baked textures get temporary
UUIDs. UUIDs are used pervasively throughout OpenSimulator and are usually
assigned by a random number generator. It's generally believed that the
probability of 2 randomly generated UUIDs not being unique is so small that
it will essentually never occur (UUIDs are essentially 128 bit integers) so
they can be used freely without risk. Of course this all depends on the
quality of the random number generator used to generate the UUIDs ;)

There are also cases where UUIDs can be generated by a hashing algorithm.
Usually in such cases this is used to detect and prevent duplicate data
being stored, i.e., if several people upload the same texture, then only
one copy of the texture need exist in an asset server that uses such a
hashing scheme.


On Sun, May 5, 2013 at 3:53 PM, Dr Ramesh Ramloll <r.ramloll at gmail.com>wrote:

> Hello,
> I understand that the UUID are unique only with respect to a given session
> of the sim. Correct me if I am wrong. So UUIDs change, this can be tested
> trivially.
> But how do notecards save avatar appearance? This would suggest the UUIDs
> of clothes or attachments would not change across sessions. So am a bit
> confused about how notecard data containing UUID pointers still work in a
> different session.
> Thanks
> Ramesh
>
> --
> 'Consider how the lilies grow. They do not labor or spin.'
> *Rameshsharma Ramloll* PhD, CEO CTO DeepSemaphore LLC, Affiliate *Research
> Associate Professor*, Idaho State University, Pocatello, ID 83209 Tel:
> 208-240-0040
> Blog <http://deepsemaphore.posterous.com/>, LinkedIn<http://www.linkedin.com/in/rameshramloll>
> , DeepSemaphore LLC <http://www.deepsemaphore.com>, Google+ profile<https://plus.google.com/103652369558830540272/about>
>
> _______________________________________________
> Opensim-users mailing list
> Opensim-users at lists.berlios.de
> https://lists.berlios.de/mailman/listinfo/opensim-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://opensimulator.org/pipermail/opensim-users/attachments/20130505/21017c54/attachment.html>