[jdev] Re: stream features and jabber:iq:auth

[Guus der Kinderen]

Hi Stefan,

First off, you need to be warned that I'm not blessed with any 
experience in jabber just yet. I'm busy educating myself by reading into 
the xmpp and jabber protocols. Please take my comments with that in 
mind. If other readers spot errors in my explanation, please don't 
hesitate to correct me.

My understanding is that the presence of a 'version=' attribute with a 
value higher than '1.0' within the opening stream tag indicates that the 
initiator works with a full implementation of the XMPP Core protocol as 
described in RFC 3920. iq-auth is not part of that RFC. Instead, it's 
described in JEP-0078 as a Final JEP (an add-on to the core protocol).

JEPs are not part of the Core XMPP protocol itself, though 
implementation of Final JEPs is advised.

As far as I see, the presence of a 'version=1.0' attribute in the 
opening stream tag doesn't indicate that you MUST NOT use 
jabber:iq:auth. It does indicate that there might be more suitable 
options available, because the presence of 'version=1.0' indicates that 
TLS/SASL is implemented, as described in RFC 3920. The precense of 
'version=1.0' does not indicate wether or not JEP-0078 (iq-auth) has 
been implemented.

I hope this helps. You can find links to descriptions of all mentioned 
protocols and standards on http://www.jabber.org/protocol/

 - Guus