Multiple authentication sources with the same category

Question

Quote from portal help:
"Multiple authentication sources can use the same category. However, because the prefix is prepended to the user and group names, you need to be certain that the domains involved do not have different users or groups with the same name. That is, if a LizaR user exists on one domain, and a LizaR user exists on another domain, they must be the same user because only one user will be created."
Fine, let's say I am "certain that the domains involved do not have different users or groups with the same name".
But there is other concern I have here. I want to know how portal will RECOGNIZE which authentication source to use?
Let's say I have 2 auth sources AS1 and AS2 with the same category MyAuth. AS1 use WS1 to authenticate against LDAP1 and AS2 use WS2 to authenticate against LDAP2.
Now, I have a user - Dmitry. I am trying to login into portal and I selected AS1 to do actual authentication. My question is how portal will CHOOSE which auth source to use because all portal knows about me is <MyAuth\Dmitry> that is came from portal login screen? Both auth sources match this pattern so seems like portal may choose any of them.
Does it mean that portal will try to authenticate again AS1 and if this attempt failed then you AS2?
I didn't find any explanation in portal documentation.
Thank you.
Edited by Bryazgin at 12/12/2007 10:42 AM

Answer 1

Yes, it seems you are right. As soon as portal have found CORRECT user there is no issue anymore because user is bind to unique auth source that actually has been used to created this user.
I think my main confusion come from the fact that having <Category> and <UserName> is not enough to UNIQUE identify user in portal as soon as <Category> can be the SAME for different auth sources.
Let's have you have user created by AS1. According API this user created by this AS1 will have 4 different names, like sUniqueName, sAuthenticationName, sLoginName and sDisplayName. But portal is going to search user in portal database BASED on information that is available in login form - <Category> and <User Name>. At this point portal has no idea about sUniqueName and all this things.
Now if there were 2 users in database that have been created by 2 different auth sources with the same <category> and <User Name> then I don't understand how portal will figured out which user to choose from. I guess <Category> value somehow MUST participate in sUniqueName value. <Category> has to be involve in process of finding user in database. In this scenario 2 users will be retrieved from database and what is important these 2 users are different, they have been created by different auth sources. Now question became which user is CORRECT one?
Edited by Bryazgin at 12/12/2007 1:34 PM