Hi Jeff,

Thanks a lot for the review and feedback.

Please refer to my feedback to Ketan where elaborated more about why for label 
protocol migrations IE 46 is useful.

  *   I'm not sure the FIB is the right place to collect this data though, 
since most of meta-data has already been lost (flattened FIB structures often 
contain bare minimum) and really heavily depends on the implementation.

I quote from the previous feedback to Ketan:

I am not sure if you have seen the presentation in IETF 108 at OPSAWG and 

Slide 2 shows Cisco as example vendor which implemented IE 46, MPLS Label Type 
identifier. There is an open ddts where vendor feasibility has been clarified.

I do understand your point that not all the vendors are capable to implement IE 
46. But that's not the point about the IPFIX IE registry. The IE registry 
enables that an IPFIX implementation can refer to the right code point. With 
RFC 5102 the decision has been made that MPLS Label Type identifier make sense 
and can be implemented. draft-tgraf-ipfix-mpls-sr-label-type just extends the 
IE 46 registry with the Segment Routing label protocol code points so when 
OSPFv2/OSPFv3/ISIS SR TLV is used, and IE 46 is supported, the IPFIX 
implementation can point to the right code point.

I hope this makes sense. Looking forward to your feedback.

Best Wishes

From: Jeff Tantsura <jefftant.i...@gmail.com>
Sent: Friday, August 14, 2020 8:54 PM
To: Graf Thomas, INI-NET-DCF <thomas.g...@swisscom.com>; han...@gredler.at; 
Ketan Talaulikar (ketant) <ketant=40cisco....@dmarc.ietf.org>
Cc: lsr@ietf.org; SPRING WG <spr...@ietf.org>
Subject: Re: [spring] [Lsr] draft-tgraf-ipfix-mpls-sr-label-type

In general, I agree with what Ketan said, what's important - it is the value 
that is being used in forwarding, even if multiple control plane entries exist, 
think about IGP migrations, or LDP to SR, where more than 1 protocol could be 
distributing the labels/SIDs. I'm not sure the FIB is the right place to 
collect this data though, since most of meta-data has already been lost 
(flattened FIB structures often contain bare minimum) and really heavily 
depends on the implementation.

On Aug 14, 2020, 10:36 AM -0700, Ketan Talaulikar (ketant) 

< also copying Spring WG for their review/inputs >

Hi Thomas/All,

I have reviewed the draft and would like to share a different perspective.

What or how much value be there on determining whether a SR Prefix SID was 
signalled/programmed on a node via OSPFv2/OSPFv3/ISIS - what matters and is 
more important is that it is a Prefix SID. Hardly any deployments would be 
running multiple protocols and learning the same prefix from different IGPs. 
IPFIX may be picking this information from a FIB in some implementation where 
the protocol does not matter and this information is not available therein.

On some nodes, the same Prefix SID may be learnt via both BGP and IGP - what 
would we use/show?

I would recommend using SR Prefix SID, SR Adjacency SID, SR Binding SID, SR BGP 
Peering SID and so on ... for the MPLS Label Type.

This also takes away the need for the second table that is being proposed to a 
large extent. For that table proposal, it is very difficult and in some cases 
not possible to different between Prefix and Node and Anycast SID. Many of 
these types are control plane elements and we can be sure more get added. Is 
there really much value in differentiation between say an Adjacency SID and LAN 
Adjacency SID?

Could we evaluate the implementation overhead and complexity of this level of 
categorization/information in IPFIX against their value in flow analysis to 
perhaps consider a middle ground?


From: Lsr <lsr-boun...@ietf.org<mailto:lsr-boun...@ietf.org>> On Behalf Of 
Sent: 31 July 2020 20:52
To: han...@gredler.at<mailto:han...@gredler.at>
Cc: lsr@ietf.org<mailto:lsr@ietf.org>
Subject: Re: [Lsr] draft-tgraf-ipfix-mpls-sr-label-type

Hi Hannes,

Thanks a lot for the feedback. Yes, makes completely sense. Will take it for 
the next update...

Best Wishes

From: Hannes Gredler <han...@gredler.at<mailto:han...@gredler.at>>
Sent: Wednesday, July 29, 2020 9:31 AM
To: Graf Thomas, INI-NET-DCF 
Cc: lsr@ietf.org<mailto:lsr@ietf.org>
Subject: Re: [Lsr] draft-tgraf-ipfix-mpls-sr-label-type


I have one comment/suggestion to Paragraph 4 (IANA Considerations).

Please add also a code point for BGP Prefix-SID - it's quite popular in DC 



On 28.07.2020, at 10:11, 
thomas.g...@swisscom.com<mailto:thomas.g...@swisscom.com> wrote:

Dear lsr,

I presented the following draft

Export of MPLS Segment Routing Label Type Information in IP Flow Information 
Export (IPFIX)

at the spring working group at IETF 108 yesterday

and today at OPSAWG where I call for adoption.

This draft adds additional segment routing code points for in the IANA IPFIX 
registry for IS-IS, OPSFv2 and OPSF v3 and segment routing SID types to gain 
further insights into the MPLS-SR forwarding-plane.

I have been asked to not only gather feedback from spring and opsawg but also 
from lsr and mpls working groups since these code points are related to link 
state routing protocols and mpls data plane.

I am looking forward to your feedback and input.

Best Wishes
Thomas Graf
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