Subject: Re: [Megaco] H248 Subtract

From: [email-masked]
Date: Fri, 5 Oct 2001 23:20:13 +0530

Hi Terry

You are right...but I think you missed out Audit{Media, Statistics}.
Actually there are only two scenarios when statistics are returned in SUBTRACT
reply.
-    Either audit desc is missing in SUBTRACT request. (default)
-    Or, audit desc is present with statistics token in SUBTRACT request.
(explicitly requested)
I distinctly remember that there was a clarification on this special behaviour
of audit descriptor in SUBTRACT, in the IG (version probably 13-14 November,
2000). But, it was dropped somewhere in between....wondering why ?
Do we again need to add the clarification ?

-Kapil Nayar
Hughes Software Systems

Terry L Anderson <[email-masked]> on 10/05/2001 09:47:40 PM

To:   Sean Leahy <[email-masked]>
cc:   [email-masked] (bcc: Kapil Nayar/HSS)

Subject:  Re: [Megaco] H248 Subtract

I guess this is a little ambiguous.  I am not quite sure why Statistics was
made "default" but I would assume that if an Audit descriptor is included then
ONLY those items specified would be returned (e.g., Audit{Media} would return
only media descriptors and NOT statistics) and that the "default" would only
occur if there was no Audit descriptor.  So Audit{} would turn off all audit,
Audit{Media} would return Media and omitting Audit would return Statistics.

Does anyone disagree?  Do folks think this needs to be clarified in IG?

Sean Leahy wrote:

> Re: Your statement that:
>
> "...... to suppress the default one must send an empty Audit descriptor
> Audit{}.".
>
> Would it not be useful to be able to suppress statistics whilst still being
> able to ask for other information e.g. Media descriptors ?
>
> Sean Leahy

--

------------------------------------------------------------
Terry L Anderson              mailto:[email-masked]
Tel:908.582.7013   Fax:908.582.6729
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From: Terry L Anderson <[email-masked]>
Date: Fri, 05 Oct 2001 14:30:58 -0400

> You are right...but I think you missed out Audit{Media, Statistics}.

Sorry, I assumed that that one was obvious (that you got Statistics if you
explicitly asked for them), but you are certainly correct.

> Do we again need to add the clarification ?

Item 6.26 indicates explicitely that Subtract is an exception to the rule that a
missing Audit Descriptor is equivalent to an empty Audit Descriptor, but there is
no item clarifying when the "default" applies.

I propose to modify the paragraph in 7.2.3:

The AuditDescriptor is optional.  If present, the command will return [remove-
those descriptors as] only those descriptors specified in the AuditDescriptor
[add-], which may be empty.  If omitted, the default Statistics descriptor is
returned. Possible...

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