Re: [IPFIX] ipfix mib export and context information

Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> Thu, 07 July 2011 11:01 UTC

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Date: Thu, 7 Jul 2011 13:01:02 +0200
From: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
To: Benoit Claise <bclaise@cisco.com>
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Subject: Re: [IPFIX] ipfix mib export and context information
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On Thu, Jul 07, 2011 at 12:29:15PM +0200, Benoit Claise wrote:
> Dear all,
> 
> Let me ask the question differently.
> Do you see a use case for the export, within a single flow record,
> of MIB variables from different SNMP contexts?

Depends on the definition of "flow". As long as we keep the definition
found in RFC 3917 section 2.1, the likelihood of exporting MIB
variables from different SNMP context for a single flow record is
likely diminishing small.

That said, I think the main use case for MIB variable export via IPFIX
seems to be related to a much more liberal definition of a "flow",
that is, one uses IPFIX to simply stream MIB variables towards a
collector instead of polling them, likely independent of any traffic
flows. In such a scenario, the likelihood to want different SNMP
contexts in a single flow record might increase, but it might still be
acceptable to have a limitation that a single flow record can only
carry data from a single context (since SNMP has kind of the same
restriction - a PDU is always bound to a specific context).

So I guess my answer is "no", I do not see a strong use case for
having data from different contexts in a single flow record (but
different flow records should be able to carry data from different
SNMP contexts).

/js

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: +49 421 200 3587         Campus Ring 1, 28759 Bremen, Germany
Fax:   +49 421 200 3103         <http://www.jacobs-university.de/>