Subject: [AAA-WG]: Issue: Collection of Accounting data

From: "Fredrik Johansson" <[email-masked]>
Date: Mon, 25 Feb 2002 17:31:20 +0100

Submitter name:
Submitter email address: [email-masked]
Date first submitted: 25 Feb, 2002
Reference:
Document: base
Comment type: T
Priority: 1
Section: base 9.2,
Rationale/Explanation of issue:

"9.2  Protocol Messages

   A Diameter node that receives a successful authentication and/or
   authorization messages from the Home AAA Server, MUST collect
   accounting information for the session. The Accounting-Request
   message is used to transmit the accounting information to the Home
   AAA server, which MUST reply with the Accounting-Answer message to
   confirm reception..."

Why must a accounting message be sent to the Home AAA Server? In the case of
Mobile IP, it's quite likely that the operator owning the FA would like to
receive the Fa generated accounting records in order to be able to send an
invoice to the owner of the mobile node.

Suggested solution:

alt 1.
Not put any restrictions on where to send accounting data, leave it up to
the operator to configure the realm routing table correct. I.e. on can send
accounting data to a accounting server in the home domain or to a accounting
server in the access network.

alt 2.
By letting each server tell the client in the authentication answer that it
would like to receive accounting data. The Aaa-h server can say to which
server it would like the data to be sent to. And the Aaa-f can add a AVP
saying where it would like the data to be sent. This way both the owner of
the home network and the owner of the access network will receive accounting
data. To any server with their domains.

/Fredrik

---

From: Jari Arkko <[email-masked]>
Date: Tue, 26 Feb 2002 10:33:52 +0200

> invoice to the owner of the mobile node.

There's actually two issues. One, what is the first hop of the message.
Two, what is the final server that receives the message. The current
text is somewhat vague or incorrect on these two aspects. But let
me argue a few points first:

* The Fa *can't* send an invoice to the owner of the mobile node.
  There is no contract. Typically, both home and the foreign operator
  get a copy of an accounting record, and the home bills the user.
  The home and foreign settle their bills monthly. (Even if this
  wasn't the case always, I believe the home would like to get
  a copy of the accounting record in any case.)

* We have talked about separate AAA servers for authentication
  and accounting, even accounting-only application of Diameter.
  These should be accommodated somehow.

In conclusion I think the text you pointed out is (a) correct
in the sense that the accounting data has to get to the home
(b) misleading in the sense that it doesn't talk about the
servers on the path receiving/logging the records too, and (c)
incorrect in the sense that exactly the same Home AAA Server
is needed as for all As.

My proposal is to modify the text as follows:

9.2  Protocol Messages

A Diameter node that receives a successful authentication and/or
authorization messages from a Home AAA Server, MUST collect
accounting information for the session. Diameter nodes MAY also
collect accounting information for services that do not involve
authentication and/or authorization.

The Accounting-Request message is used to transmit the accounting
information. The message's final destination is a Home AAA Server
(not necessarily the same one as above). On the path towards this
server, local and broker Diameter Agents MAY record the same
accounting information, e.g. for the purposes of inter-operator
settlements. The Home AAA server MUST reply with the
Accounting-Answer message to confirm reception of the
Accounting-Request message.