[Opensim-dev] rex auth & avatar systems (Re: future rexviewer merger)

[Toni Alatalo]

On Dec 6, 2008, at 12:18 PM, Ryan McDougall wrote:
> On Sat, Dec 6, 2008 at 3:47 AM, Melanie <melanie at t-data.com> wrote:
>> Also, I see anumber of abuse scenarios possible with the
>> login/avatar service (commercial abuse), which is why I personally
>> favor a different model. Specifically, to keep the avatar appearance
>> data on the client and not on any server at all.
> Lets keep talking about this, but perhaps on a different thread.

Ok this tries to be that now.

Melanie, the avatar storage server is a piece of software that you can  
host in any way you want - if you want to run one coupled with a  
viewer, just do.

About keeping avatar appearance data on the client, what would that  
mean for a user that uses several different clients on different  
machines?

I think the guts of these designs are the division of the systems into  
components, and the interfaces (protocols) between the components - not  
so much the configuration of where what is run, if/as the protocols are  
independent of that question.

The current Rex implementation is described in  
http://www.rexdeveloper.org/wiki/index.php? 
title=Introduction_to_realXtend_Server_Platform

With regard to avatar assets, I think that picture is not actually not  
complete: IIRC the world server (opensim) basically relays Avatar URLs  
to clients, and clients connect the Avatar Storage server directly to  
get the appearance etc. So you can run your own, next to the client if  
you want, provided that other clients can connect to your client's box  
to get your avatar data.

I personally like services that are on servers, like for example use  
IMAP for email & screen+irssi on a server for irc to not depend on any  
particular client computer, 'cause often need to switch them several  
times within a day even. But needs differ, so like said I think systems  
and protocols should enable many kinds of configurations.

Diva had some basic questions of the Rex model too, let's see if I can  
clarify any of that..

>>>> Diva Canto wrote:
>>>>> As Rex's extensions move closer to opensim (I'm in the group of  
>>>>> people
>>>>> who can't wait to see meshes and better graphics!), it will be  
>>>>> good to

btw I think that the Ogre / mesh support should be an independent  
module, not coupled to other Rex stuff as it is orthogonal to the  
authentication & avatar storage issues. but that's yet another thread..

>>>>> the use of "avatar" here, as we know that opensim uses it to  
>>>>> denote a
>>>>> pixelated carcass, that's neither a user nor an agent. And in Rex  
>>>>> the
>>>>> "avatar system" seems like it's more of a user storage/asset  
>>>>> system.
>>>>> Part of the user's storage/assets includes the pixelated carcass  
>>>>> for
>>>>> opensim-based worlds that care about that; but it includes all  
>>>>> other
>>>>> assets owned by the user.

yes, I've also been confused there at times. basically the picture in  
the wiki page i posted above tells it: the Rex model introduces two new  
servers, with new protocols: the 1) authentication server and 2) avatar  
storage server. the authentication server has user accounts, and for  
each a reference to the avatar data of that user.

>>>>> It would be interesting to compare existing efforts in opensim  
>>>>> such as
>>>>> the Hypergrid and the distributed asset server with Rex's avatar  
>>>>> system.
>>>>> Is it possible that
>>>>> Hypergrid+DAS >= Rex's Avatar System ?
>>>>> What else does the avatar system bring to the table?

indeed.

the idea with the Rex system is that anyone can host world servers or  
grids, that the users can use with their existing accounts, so that  
their avatars also work. no hypergrid or other such configuration is  
required, but the sims/grids need to know the authentication servers  
that they trust. there's a sequence diagram of the login procedure but  
i couldn't find it in the wiki now - basically it works so that the  
client first connects the auth server, gets a nonce, relays that to the  
sim which verifies it from the auth server and logs the user in. so you  
can add another world server/grid, trust some existing auth server(s),  
and welcome users. and like said in response to Melanie above, the  
clients then get the appearances of other avatars there from the  
storage servers of those avatars, and the world servers don't need to  
touch them.

the distributed asset server may well be similar to the rex avatar  
asset server, we're going to look more into that, and the idea has been  
to generalize so that all assets could be distributed.

do note that both these were implemented a year ago, and published in  
last February, so back then they brought all this to the table as no  
DAS, Hypergrid nor OGP existed yet. but certainly the job now is to  
look at all of these to get the picture, and Rex as a project is  
prepared to refactor / drop&replace things - it has been rapid  
prototyping, but the goal is to get a solid base and hopefully  
standards.

>>>>> Crista

~Toni