A placeholder for now, more info to follow.
A short reference to the web3d-blog.
Dirk Krause/Bartholomew Kleiber
 Serious Games Whitepaper
References to look at
very interesting XEP here:
 This specification defines an XMPP extension for delegating access to protected resources over XMPP, using the OAuth protocol. In the language of OAuth, a User can authorize a Consumer to access a Protected Resource that is hosted by a Service Provider; this authorization is encapsulated in a token that the User requests from the Service Provider, that the User shares with the Consumer, and that the Consumer then presents to the Service Provider in an access request. This specification assumes that OAuth tokens will be acquired via HTTP as defined in the core OAuth specification, then presented over XMPP to a Service Provider. The Protected Resources accessible over XMPP might include groupchat rooms, data feeds hosted at publish-subscribe nodes, media relays, communication gateways, and other items of interest.
 code example.
 C# and python implementation among others.
 German ZODB introduction.
 Jabber Inc SIP RTP XMPP White Paper (ePaper)
 General SIP Whitepapers