RE: : 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? 

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.

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

Doesn't parse.

> 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.

> 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.

> 
> 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.
  
> 
> 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