Subject: RE: [AAA-WG]: Issue 235

From: "Patil Basavaraj (NET/Dallas)" <[email-masked]>
Date: Tue, 20 Nov 2001 09:12:31 -0600

Comments below:

> Two  of these may be rejected (235, 243), one is still being discussed
(221) 
> and the last one I don't know what to do with (241).
> 
> I would appreciate receiving some response from the WG on 
> these last issues.
> 
> Thanks,
> 
> PatC
>

Issue 235 enables Diameter to be far more efficient on the aspect of
accounting records uniqueness checking. In order for Diameter to be
broadly applicable as an accounting protocol in different networks and
specifically in scenarios where real-time accounting is required issue
235 should be considered as being important. 

Note that adding the support for the "D" bit will still allow
uniqueness checking to be performed the same way (every record against
every other record) as suggested in the draft now. However with the
"D" bit support it is quite possible that implementations can be far
more efficient.

Requested change/Text to be added
---------------------------------- 

To include in section 3.0  Diameter Header the 'D' bit as shown in:

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |R P E D r|                  Command-Code                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

and the explanation of this bit (after the description of the 'E' bit): 

      (possibly) D(uplicated)
                  - This bit is defined only for Accounting Requests,
		  sent by a Diameter node or proxy. If set, the
		  message is possibly a duplicate, and must be later
		  checked by a recipient node for duplicate occurences.
		  If sending a message for the first time, this bit
		  MUST be cleared.  
                  This bit MUST NOT be set if an answer message
		  (e.g. a protocol error) has been received for an
		  earlier similar message. It shoulf be used only in
		  cases where no answer has been received from the
		  primary agent for a message and the message is  sent
		  again (e.g. due to a failover, to an alternate agent
		  or to a recovered primary peer node).

and to section 9.4  Fault Resilience, 
after the 2nd paragraph ending with the sentence "This detection MUST
be based on the inspection of the Session-Id and
Accounting-Record-Number AVP pairs.",

the following new sentence needs to be appended:

   "The inspection MUST be performed at least for such records
   that arrived at the Diameter peer (in accounting messages)
   which have the 'D' bit set."

-Basavaraj