Subject: [OPSAWG] Comments on draft-akhter-opsawg-perfmon-ipfix-02

From: "Jan Novak (janovak)" <[email-masked]>
Date: Tue, 22 May 2012 10:58:00 +0200

Hi Amer,

I have reviewed your draft draft-akhter-opsawg-perfmon-ipfix-02.txt.

There seems to be a lot of text overlap with your methodology
document - section 1,3, 4 could probably be abbreviated or omitted
leaving the document just with raw IPFIX IE specifications or just
add the IE specification as sub-sections or a new section into
the first document ?? 

Section 2 uses definitions from RFC5610 - I think those you use there
are defined in RFC5102 as DataTypeSemantic, units and range while
RFC5610 specifies how this information should be exported - here
you are defining the IE itself so you should use the definitions
from RFC5102

Also the methodology documents already speaks in terms of IPFIX
IEs while you are trying to specify some performance metrics - the
methodology could have names and an exact definitions of the metric
and then a reference which IE represents the particular metric

RFC5102 section 2.1 specifies a template for IEs with a MUST
so the MUST entries should be literally followed in your IEs spec
- namely name, elementID, description, dataType and status.

RFC5102 section 2.1 specifies MAY entries for the template - like
DataTypeSemantic, units, name - might be preferable to follow the
naming as well

You interchanged ElementId with name - ElementId should be the
numerical ID of the particular IE, while name of the IE is actually
missing

Instead of using Observation Point - wouldn't be the scope of the
element
appropriate ?? Or if not then scope should be actually added - are the 
metrics (like perfPacketLoss) applicable to all the traffic seen
by the UUT (or more specifically passing through the Observation
Point) or to just individual flows ?? This should also be part of the
particular metric definition.

Will your IEs be enterprise IEs or IANA ones ??

Section 4.1.2 - Units packets ??

Section 4.1.3 - there is a mis-match between the definition and the
range 
- it should be limited to 0 - 100 + a value when the rate is unknown
This definition is also missing in section 4.1.3 of your methodology

Sections 4.3.1, 4.3.2 - the values are just numbers/ids so units
shouldn't be octets but "none" ??

The IPFIX guys here have had few discussions regarding IE definitions
explosions with all the needs like this - have you thought using RFC6313
now
(structured data) ??

I am not sure I would use RFC2321 as a reference work :-).
huic-ipfix-sipfix is not a work in progress - the ID expired 3 years
ago.
ie-doctors is a WG doc version 2 now -
draft-ietf-ipfix-ie-doctors-02.txt
pmol-metrics-framework is RFC 6390

The document would benefit from running it through spell checker.

Rgds, Jan

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and the strong envy them.
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