Subject: RE: [AAA-WG]: Re: Comments: draft-belinchon-aaa-diameter-mm-app-0 1.txt

From: "Daniel Warren" <[email-masked]>
Date: Wed, 9 Jul 2003 12:42:39 +0100

If User-Name AVP is made optional, what is the impact of the text in 5.2
that reads...

'At reception of the Diameter UAR message, the Diameter server MUST
   verify the existence of the user in the realm, i.e., the User-Name
   AVP value is a valid user within that realm. If the Diameter server
   does not recognize the user name received in the User-Name AVP, the
   Diameter server MUST build a Diameter User-Authorization-Answer (UAA)
   message and MUST set the Result-Code AVP to
   DIAMETER_ERROR_USER_UNKNOWN.

   Then Diameter server MUST authorize that User-Name AVP value is able
   to register the SIP or SIPS URI included in the
   SIP-Public-User-Identity AVP. If this authorization fails, the
   Diameter server must set the Result-Code AVP to
   DIAMETER_ERROR_IDENTITIES_DONT_MATCH and send it in a Diameter
   User-Authorization-Answer (UAA) message.'

If the User-Name AVP is made optional, is this behaviour still valid?
Making User-Name AVP optional would seem to me to imply that any time it is
missing, UAA has to report an error.  Either it has to be mandatory or this
behaviour needs to change too.

Dan Warren

-------------------------------

> Section 5.1
> - In Open Issue Note, you have mentioned User-Name AVP being the mandatory
>   parameter. I would think that UAR may be used for other SIP Requests
> as well
>   (other than REGISTER). In those cases, do we have private id available 
> also?

I agree with you. I am sure that the username AVP will not be available in 
general, in all requests. It might be get acquiered, but that requires the 
SIP proxy to challenge the user.

So this open issue is just an action point to make the AVP optional and 
discuss what are the procedures in the Diameter server when the AVP is not 
present in the UAR.

---

From: "Miguel A. Garcia" <[email-masked]>
Date: Wed, 09 Jul 2003 15:15:40 +0300

Dan:

Of course that text will have be revisited if User-Name AVP is optional. 
But the fact is that, no matter what we write in the document, User-Name is 
optional except in 3GPP networks. 3GPP has optimized the flow to avoid two 
roundtrips, and therefore, User-Name comes in the first roundtrip. But this 
is not always the behaviour in an internet client.

So the reason whey I noted down an Open Issue was to synchronize the 
behaviour when User-Name is available and when not. This will require to 
rewrite substantial parts of the document that assume User-Name is always 
available.

/Miguel

Daniel Warren wrote:
> Making User-Name AVP optional would seem to me to imply that any time it 
> is missing, UAA has to report an error.  Either it has to be mandatory 
> or this behaviour needs to change too.
> 
> Dan Warren
> 

-- 
Miguel-Angel Garcia                     Oy LM Ericsson AB
                                         Jorvas, Finland
mailto:[email-masked]     Phone:  +358 9 299 3553
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