Re: [mpls] Open DT agenda for 2021-09-09

[Loa Andersson <[e-mail]>]

Sure, it is on the agenda. 

/Loa

Sent from my iPhone

> On 8 Sep 2021, at 21:41, John E Drake <[e-mail]> wrote:
> 
> Loa,
> 
> Perhaps this is something we can discuss at an upcoming DT meeting?
> 
> Yours Irrespectively,
> 
> John
> 
> 
> Juniper Business Use Only
> 
>> -----Original Message-----
>> From: Loa Andersson <[e-mail]>
>> Sent: Wednesday, September 8, 2021 3:38 PM
>> To: John E Drake <[e-mail]>
>> Cc: Loa Andersson <[e-mail]>; [e-mail]; [e-mail]; mpls-
>> [e-mail]; DetNet Chairs <[e-mail]>
>> Subject: Re: [mpls] Open DT agenda for 2021-09-09
>> 
>> [External Email. Be cautious of content]
>> 
>> 
>> John,
>> 
>> Please look at what Kireeti wrote on the MIAD page on the wiki. I think is his
>> latest contribution to that discussion. After that I have mail and addition to my
>> “thoughts” (at the bottom.
>> 
>> /Loa
>> 
>> Sent from my iPhone
>> 
>>> On 8 Sep 2021, at 21:29, John E Drake <jdrake=[e-mail]>
>> wrote:
>>> 
>>> Loa,
>>> 
>>> Comments inline below.
>>> 
>>> Yours Irrespectively,
>>> 
>>> John
>>> 
>>> 
>>> Juniper Business Use Only
>>> 
>>>> -----Original Message-----
>>>> From: Loa Andersson <[e-mail]>
>>>> Sent: Wednesday, September 8, 2021 3:06 PM
>>>> To: John E Drake <[e-mail]>; [e-mail]
>>>> Cc: [e-mail]; [e-mail]; DetNet Chairs
>>>> <detnet- [e-mail]>
>>>> Subject: Re: [mpls] Open DT agenda for 2021-09-09
>>>> 
>>>> [External Email. Be cautious of content]
>>>> 
>>>> 
>>>> John,
>>>> 
>>>> Tnx for comments.
>>>> 
>>>> There is a couple of thing we need to converged on. For example how
>>>> we use "Ancillary data".
>>>> 
>>>> Both you and me seem to mean what Kireeti call "post stack data" when
>>>> we say "ancillary data".
>>>> 
>>>> To me it seem that Kireeti works with three "variants" of ancillary
>>>> data
>>>> - no data
>>>> - in stack data
>>>> - post stack data
>>>> 
>>>> In an earlier mail I pointed to an addition to my text I promised to
>>>> align my text with whatever terminology we agreed to on Thursday.
>>>> 
>>>> We might even include a terminology section in the
>>>> Framework/Architecture document.
>>>> 
>>>>>> On 08/09/2021 17:35, John E Drake wrote:
>>>>>> Loa,
>>>>>> 
>>>>>> Regarding your "Thoughts on Encapsulating ancillary data", I think
>>>>>> we need to
>>>>> define for a given forwarding action whether it requires ancillary data.
>>>>> Yes - I say that in my text also. A bit cryptic, but the assumption section says:
>>>>> 
>>>>>   "Which flags that are "no-data", "in-stack-data" or "after-the-BoS-
>>>>>    data" is not decided here, but when the flags flags are specified.
>>>>>    This is just EXAMPLES to be used for explanatory purpose."
>>>>> 
>>>>> Yes so I agree, actually we need to specify which variant of data
>>>>> that is needed when a flag is specified.
>>>>> 
>>>>> I agree with Kireeti that any ancillary data required by forwarding
>>>>> actions should be encoded in the MPLS label stack.
>>>>> 
>>>>> I don't think Kireeti says that, he operates with three variants, "no
>>>>> data", "in- stack data", and "post-stack"
>>> 
>>> [JD]  My recollection is that Kireeti said this in a DT meeting and I think it
>> makes sense, given that some implementations have trouble finding the BoS.
>>> 
>>>> 
>>>> So, what we should have is an LSE containing the forwarding actions
>>>> followed by LSEs for each forwarding action that requires ancillary data.
>>>> 
>>>> Here I don't follow, the post stack data is not an LSE. But the TLV
>>>> structure I defined does that, kind of.
>>> 
>>> [JD]  If the ancillary data applies to forwarding actions I was placing it in the
>> label stack.
>>> 
>>>> 
>>>> These LSEs should be in the same order in which the forwarding
>>>> actions are defined;  if forwarding actions 1, 3, and 5 require
>>>> ancillary data, then following the LSE containing the forwarding
>>>> actions there should be three LSEs, for forwarding actions 1, 3, and 5.
>>>> 
>>>> Yes, that could work, if the flag position is put in the flag field
>>>> in the order they are defined. I think that is the same thing as to
>>>> say as the flags representing the forwarding action appears in flag field.
>>>>> 
>>>>> I also think we need to specify that a transit node should only
>>>>> process the
>>>> forwarding actions it understands and ignore the others, and that
>>>> when constructing the FAI LSEs the ingress node should only include
>>>> forwarding actions understood both by it and by the egress node.  I
>>>> think the implication of these rules is that a every node needs to
>>>> understand every bit in the forwarding actions up to a given bit
>>>> position.  I.e., it can't selectively support individual forwarding actions.
>>>> 
>>>> I think this is a strong possibility, but it wasoutside the the scope
>>>> of the present text, when I wrote it. We could discuss and include if we
>> converge.
>>> 
>>> [JD]  I was proposing this because it is the only way of which I could think that
>> would enable incremental deployment.
>>> 
>>>> 
>>>> /Loa
>>>>> 
>>>>> Yours Irrespectively,
>>>>> 
>>>>> John
>>>>> 
>>>>> 
>>>>> Juniper Business Use Only
>>>>> 
>>>>>> -----Original Message-----
>>>>>> From: mpls <[e-mail]> On Behalf Of Loa Andersson
>>>>>> Sent: Tuesday, September 7, 2021 4:46 AM
>>>>>> To: [e-mail]
>>>>>> Cc: [e-mail]; [e-mail]; DetNet Chairs
>>>>>> <detnet- [e-mail]>
>>>>>> Subject: [mpls] Open DT agenda for 2021-09-09
>>>>>> 
>>>>>> [External Email. Be cautious of content]
>>>>>> 
>>>>>> 
>>>>>> MPLS Open DT,
>>>>>> 
>>>>>> We will have our meeting as usual meeting on Thursday (CEST 5pm).
>>>>>> 
>>>>>> Please find the agenda a:
>>>>>> 
>>>>>> https://urldefense.com/v3/__https://trac.ietf.org/trac/mpls/wiki/20
>>>>>> 21
>>>>>> -09-09-
>>>>>> agenda__;!!NEt6yMaO-
>> gk!WANhHodAhWZuqCjTWdq1kjMWURaq8utN7dc--
>>>>>> 65c9lu71w2JUVib03Ng1RrdKKk$
>>>>>> 
>>>>>> For the text on "Thoughts on Encapsulating ancillary data" I have
>>>>>> received some comments, both off-line and on-line. I have added
>>>>>> some responses at the end of the text.
>>>>>> 
>>>>>> /Loa
>>>>>> --
>>>>>> 
>>>>>> Loa Andersson                        email: [e-mail]
>>>>>> Senior MPLS Expert                          [e-mail]
>>>>>> Bronze Dragon Consulting             phone: [phone]
>>>>>> 
>>>>>> _______________________________________________
>>>>>> mpls mailing list
>>>>>> [e-mail]
>>>>>> 
>>>> 
>> https://urldefense.com/v3/__https://www.ietf.org/mailman/listinfo/mpls__;!!
>>>>>> NEt6yMaO-gk!WANhHodAhWZuqCjTWdq1kjMWURaq8utN7dc--
>>>>>> 65c9lu71w2JUVib03NgxXHPQ7M$
>>>> 
>>>> --
>>>> 
>>>> Loa Andersson                        email: [e-mail]
>>>> Senior MPLS Expert                          [e-mail]
>>>> Bronze Dragon Consulting             phone: [phone]
>>> _______________________________________________
>>> mpls mailing list
>>> [e-mail]
>>> https://urldefense.com/v3/__https://www.ietf.org/mailman/listinfo/mpls
>>> __;!!NEt6yMaO-
>> gk!U9lc_yZbwa3GJzplYtJcCYbrxwbcU0nBrMQOisbOwCT6zMdTOC22S
>>> ZAmNranjxA$