[Opensim-users] [Opensim-dev] Grid Numberging

[Frisby, Adam]

Yeah, the reason I said 'almost' wasn’t because of a good UUID generator, - it's the bad ones.

IE, people using bad random sources, etc which dramatically increase the chance of a collision - ie if you are only getting 30 bits of randomness, you could run into a collision fairly quickly.

Adam

> -----Original Message-----
> From: opensim-users-bounces at lists.berlios.de [mailto:opensim-users-
> bounces at lists.berlios.de] On Behalf Of Sean Dague
> Sent: Friday, 31 October 2008 4:48 PM
> To: opensim-users at lists.berlios.de
> Subject: Re: [Opensim-users] [Opensim-dev] Grid Numberging
>
> Dr Scofield wrote:
> > Frisby, Adam wrote:
> >> Shouldn’t UUIDs by definition be unique?
> >>
> >>
> >>
> >> IE – if your generating them randomly a collision is almost
> >> guaranteed to never ever occur.
> >
> > "almost" being a key word here...
>
> "...after generating 1 billion UUIDs every second for the next 100
> years, the probability of creating just one duplicate would be about
> 50%. The probability of one duplicate would be about 50% if every
> person on earth owns 600 million UUIDs."
>
> http://en.wikipedia.org/wiki/Uuid
>
> Just to keep "almost" in perspective,
>
>         -Sean
>
> --
> Sean Dague / Neas Bade
> sdague at gmail.com
> http://dague.net
>