RE: : Application Id in ASR, RAR and STR commands

Glen, 
please see comments in line.
Mike






"Glen Zorn \(gwz\)" <[email protected]>
27.09.2005 13:14
 
        To:     <[email protected]>, <[email protected]>
        cc: 
        Subject:        RE: [AAA-WG]: Application Id in ASR, RAR and STR 
commands


[email protected] <> supposedly scribbled:

> Hi,
>  another Diameter Base query and request for assistance - sorry!
> 
> Base defines a number of commands which are used not peer-to-peer
> (like 
> CER) but end-to-end.  These are STR/STA, RAR/RAA, ASR/ASA.
> These commands will be used within a Diameter session which has been
> set up by an application, e.g. NASREQ or CCA or a vendor specific
> application 
> 
> The question has arisen: which value does the application-id in the
> command header of these AVPs take and which AVP of
> Auth-Application-Id, Acct-Application-Id and
> Vendor-Specific-Application-Id - with which value must be used? 

BTW, I really meant: what is the value of the application-id in the 
commands ASR/ASA, RAR/RAA and STR/STA.  For the new commands which are 
defined in application, it is clear that the application id is the id of 
the defining application (AAR/AAA: 1  , CCR/CCA: 4 etc)

The app ID of the application, in the appropriate AVP.  For NASREQ, for 
example, an auth message should include the Auth-Application-Id AVP while 
an accounting message would include the Acct-Application-Id.  In both 
cases the value of the AVP would be 1, as would the value of the 
Application-ID.

Are you saying that ASR in NASREQ uses Application-Id = 1 ??

> 
> The latter question seems trivial, because Base defines the syntax of
> these AVPs only with Auth-Application-id. 

Doesn't parse.

Sorry - I meant ... the syntax of these commands defines only the 
Auth-Application-Id AVP.  in particular Vendor-Specific-Application-Id is 
not defined.  So it would seem that in a vendor specific application which 
uses sessions and ASR the only possible value is zero.


> And the other hard fact is that Base mandates the value of
> Auth-Application-Id and the application id in the header to be the
> same. 
> 
> Now I had understood the Auth-Application-Id (& co) AVPs to be
> necessary, primarily for the purpose of routing the commands to the
> right application - 
> so if, as one may initially assume, the value of the application-id
> in the ASR header (and Auth-Application-Id) is 0 (zero) then how
> would the ASR be delivered to the right application - in this case in
> the client? 

A reasonable interpretation might be that if the Application-Id is 0, then 
the effects of the message apply to all applications.

Do you mean all applications and all sessions within the application? So 
with ASR, the client should terminate ALL sessions?
Or rather that the ASR is "generally speaking potentially applicable to 
all applications and specifically speaking ...  use the Session-Id"?



> If it is not used at this point, but just the session-id AVP, then
> what is the purpose of the Auth-Application-Id AVP in these commands? 

Good question.
So maybe somebody else knows :-)

> 
> Interestingly CCA specifies explicitly that RAR/RAA shall use
> application id 4 (in the header and in Auth-Application-Id), but says
> nothiong about ASR.  NASREQ says only the commands AAR/AAA use
> application-id 1, all the rest use Base - but then goes on to add
> several AVPs to the ASR syntax, all with the M-bit set.!? 

I suspect that this is an error.
Does anybody else in the NASREQ group or Base authors have an opinion? 
 
> 
> I'd be grateful for any guidance possible!
> 
> 
> Best Regards
> 
> Mike Hillier
> 
> 
> Michael Hillier
> Mobile  +49 170 5454 121
> [email protected]

Hope this helps,

~gwz

Why is it that most of the world's problems can't be solved by simply
  listening to John Coltrane? -- Henry Gabriel