[jdev] RE: [Standards-JIG] Call for Experience:JEP-0078(Non-SASLAuthentication)

[Tijl Houtbeckers]

On Mon, 27 Sep 2004 09:52:47 +0200, Heiner Wolf <wolf at bluehands.de> wrote:

> Hello
>
> Some client have a "register automatically if the username does not
> exist" feature. How is the client supposed to learn that a username
> does not exist?

The client should attempt a full login, then it will receive an  
authentication error.

If you use inband registration that way you could find out a username if a  
username exists in most current configuations. However, it is not likely  
that a "standard" server in the future will have inband registration  
enabled. There might be a web based registration or integration with an  
existing userbase.

Basically it is up the registration system (inband or external) wether it  
wants to reveal if usernames are in use or not, not the authentication  
system.