Re: : Issue: differences betweern 3GPP SIP usage and Diameter SIP document

Do you want me to reply one by one to all these differences?

Most of the are related to "this AVP is mandatory here and optional 
there", and the reason is because 3GPP Cx assumes that there is only 
IMS-AKA authentication, where the UE sends an unsolicited Authorization 
header in the first SIP request. This is not the case for a regular SIP 
client in SIP, which works like in HTTP. So in most cases there is not 
going to be an unsoliciated Authorization header, there is not going to 
be a realm, username, etc...

I think I don't have the time to comment one by one all the issues. The 
only think I can say is that there was a reason why we relaxed the Cx 
mandatoriness of AVPs, and there are reasons why we added new AVPs, and 
most of these reasons come from moving a Diameter application that works 
in a controlled environment (such an IMS) to support the public Internet

/Miguel

Jari Arkko wrote:

> I know I'm late with this wrt WGLC, but my colleague made a list
> of differences between what's in the Diameter SIP document
> and what 3GPP Cx interface does.
> 
> Please see the list below. I realize that a standard spec
> may not match what someone else has been doing before
> and there's bound to be extensions, things done in a better
> way, etc.
> 
> However, I'd like circulate this list just to make sure that
> we understand what these differences are, and to make
> sure that these are intended differences and not accidental
> differences that will make it harder for 3GPP to switch to
> a IETF standard later (if they even want to, but that's
> another discussion).
> 
> Bigger differences:
> 
> - DIAMETER_ERROR_USER_UNKNOWN is used when the User-Name is not
> known in the draft, but in Cx when either the User-Name or the
> public identity is not known.
> 
> - In the draft, the Authentication Pending flag is cleared in the
> MAR. In the Cx, it is cleared in the SAR.
> 
> - In the draft, the SIP Server is stored in the MAR in some cases.
> In the Cx, it is only stored in the SAR.
> 
> - In the PPR in the draft User-Data is mandatory,
> in the Cx it is optional.
> 
> - In SIP-Auth-Data-Item SIP-Authentication-Scheme is mandatory,
> in the Cx it is optional.
> 
> - SIP-User-Data is a Grouped with two mandatory AVPs in the draft,
> in the Cx it is an OctetString that contains the XML data.
> 
> - In all responses in the draft Result-Code is mandatory,
> in the Cx it is optional as an alternative to Experimental-Result
> 
> - In all draft commands there is a mandatory Auth-Application-Id,
> in the Cx there is a mandatory Vendor-Specific-Application-Id.
> 
> Minor differences:
> 
> - In UAR and MAR in the draft User-Name is optional,
> in the Cx it is mandatory. The draft specifies an error for when
> the application requires a User-Name, but Cx uses a different
> error.
> 
> - The draft states that it is not possible to return SIP Server and
> capabilities in the same UAA. In the Cx it is done, but this may
> be changed.
> 
> - There are two additional responses to MAR in the draft
> (DIAMETER_SUCCESS_AUTH_SENT_SERVER_NOT_STORED and
> DIAMETER_SUCCESS_SERVER_NAME_NOT_STORED)
> 
> - In the draft, it is possible to keep Diameter sessions and use the
> STR and ASR.
> 
> - In UAR, Visited-Network-Identifier is optional in the draft and
> mandatory in Cx.
> 
> - In RTR, User-Name is optional in the draft and mandatory in Cx.
> 
> - Format of the Charging Addresses is different.
> 
> - It is possible to generate the once in the Diameter client in the
> draft.
> 
> - Authorization-Lifetime and Auth-Grace-Period are present in the draft
> in MAA, SAA, PPR, LIA and RTA (are they needed in the RTA at all?).
> 
> - In the LIA in the draft, there are Redirect-Host, Redirect-Host-Usage
> and Redirect-Max-Cache-Time, that are not in Cx.
> 
> - There is additional functions in Cx that are not in the draft, like
> barring or implicit registration.
> 
> - In the handling of the MAR in the draft, it is stated that the Diameter
> server keeps the address of the SIP server.
> 
> 
> 

-- 
Miguel A. Garcia           tel:+358-50-4804586
sip:[email protected]
Nokia Research Center      Helsinki, Finland