[jdev] confusion with subscription states in XIMP

[Jacek Konieczny]

On Thu, Jun 17, 2004 at 02:42:04PM +0200, Peter Beck wrote:
> Hi,
> 
> I'm confused about some difference between the Presence Subscription States 
> described in XIMP, capture 9 
> (http://www.jabber.org/ietf/draft-ietf-xmpp-im-22.html#substates) and the 
> behavior of real XMPP servers.
> For my understanding it is possible to send a 'subscribed' message to a 
> contact, without receiving a 'subscribe' from the contact before. In other 
> word: The user/contact relation is for example in state 'None' and changes 
> to state 'From' with sending <presence type='subscribed' to='contact' 
> from='user' />.

This is a bug of old Jabber servers. In XMPP this is illegal.

> As described in XIMP 9.2 table 1, a state change from 'None' to 'From' with 
> 'subscribed' is not possible. In other word: only after receiving a 
> 'subscribe' from the contact, the user could send a 'subscribed' to the 
> contact.

That is right. 

> If yes. What are the reasons? Maybe the behavior in XIMP is founded on 
> security concerns, but I can't expect witch.

It is not good when other entity may fill your roster without any
request from you.

Greets,
	Jacek