[Opensim-dev] Global identifiers

[Serendipity Seraph]

 On 8/30/10 2:09 PM, diva at metaverseink.com wrote:
> Hurliman, John wrote:
>> My interpretation (please correct me if I'm wrong) is that there is
>> rough consensus on the overall strategy, but an open question of how
>> to encode global identities when cross-grid communication (or
>> out-of-grid archiving) happens. 
>
> That's what's going on.
> Up to now, all global identifiers (that already exist) have been
> volatile; nothing has persisted. As I found myself writing code that
> would inject global identifiers into a DB table, I thought we should
> all talk about the form of such identifiers.
>
>> There is probably also a hidden question of how to mark a local
>> account as linked to a foreign identity, which may solve the
>> friending issue. If I am friends with your avatar and we are both on
>> grid B but your avatar actually originated from grid A, that link in
>> the profile is what can tip off the presence service to try a remote
>> presence check (assuming the user is not online in the local grid).
>> My only interest in these low level questions like how the global
>> identifiers and profile links look is what the final decision is so I
>> can implement it in the OpenSim SimianGrid connectors.
>
> Well, we distinguish "user accounts" from "grid users" -- these are 2
> different interfaces, although implementers may decide to collapse
> them. But they are different concepts. User accounts are the
> locally-registered users; in some cases, like for example, the UCI
> grid, there's only some people who can get accounts there, namely
> people associated with the university. Grid users are users that are
> referenced by things that happen in the grid. So we already have an
> interface for that, although now I'm thinking that perhaps we need to
> separate its UserID field into 2 things: a local UUID and a reference
> to the external name. And I guess that's my main issue at this point.
>
It seems more reasonable in a distributed system to say that an X is an
X - a User is a User, whether they originally were instantiated on a
local or a remote system.   So I would go for collapsing the two as much
as possible as a matter of policy.  Otherwise freedom to move between
nodes in the system is more limited and there is more special case logic
to deal with.    But that is speaking from a general distributed
computing perspective.  There may be many Opensim details that make that
seemingly ideal position in practice rather naive.

- s