> On May 17, 2024, at 17:14, Acee Lindem <acee.lin...@gmail.com> wrote:
> 
> Hi Ketan, Shraddha,
> 
>> On May 17, 2024, at 07:22, Ketan Talaulikar <ketant.i...@gmail.com 
>> <mailto:ketant.i...@gmail.com>> wrote:
>> 
>> Hi Shraddha,
>> 
>> Thanks for your response. I believe we now have only one open discussion 
>> point and hence I am top posting my suggestions.
>> 
>> If the authors wish to cover the Generic Metric TLV usage in TE Opaque LSAs 
>> in this document then we will need more text/specification than "All 
>> traditional TE applications like CSPF/RSVP make use of link-attributes from 
>> TE-LSA."
> 
> Since the new Generic Metric code point is in this registry - 
> https://www.iana.org/assignments/ospf-traffic-eng-tlvs/ospf-traffic-eng-tlvs.xhtml#subtlv2
>  I don’t the issue with it being used for TE applications currently making 
> use of the TE Opaque LSA - we’re still using the OSPF TE Opaque LSA for 
> traditional TE. Right? 
> 
> 
>> 
>> Some suggestions which can be incorporated in a separate section that is 
>> titled "Use of Generic Metric for RSVP-TE":
>> - specify that Generic Metric TLV usage in TE Opaque LSAs is limited to 
>> RSVP-TE use
>> - specify the differences for use of bandwidth metric for RSVP-TE; I assume 
>> it is a constant metric value itself since we don't have FAD to determine 
>> the b/w metric
>> - flex algo prunes links w/o the specific metric advertisements; will it be 
>> the same for RSVP-TE CSPF?
>> - cover backward compatibility aspects (e.g., what if the computation needs 
>> to optimize on a particular metric and a set of routers/links don't carry 
>> that metric value)
>> 
>> I hope this gives an idea of the details necessary if this document is 
>> attempting to cover use of generic metric for not just flex algo but other 
>> applications. If there were any other applications/usage in mind, it would 
>> be good to clarify that explicitly. We have many different LSAs in OSPF 
>> resulting in potential interop issues if the specifications are not clear.
> 
> Perhaps, it should be stated that usage will be specified in future 
> documents. This could included in the -13 version with Peter’s comments.  

On second thought, since RSVP signals the complete path, the TE path 
computation typically has not be standardized and I don’t think this is 
required. We can move forward with the -13 version with Peter’s comments. 

Thanks,
Acee





> 
> Thanks,
> Acee
> 
> 
> 
> 
>> 
>> Thanks,
>> Ketan
>> 
>> 
>> On Thu, May 16, 2024 at 2:56 PM Shraddha Hegde <shrad...@juniper.net 
>> <mailto:shrad...@juniper.net>> wrote:
>>> Hi Ketan,
>>> 
>>>  
>>> 
>>> Snipping to open points
>>> 
>>>  
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 2) This comment is specific to OSPF given the encoding differences it has 
>>> with ISIS. Section 2.2 allows for Generic Metric TLV to be used in too many 
>>> places without clear specification of what it is used for - this is a 
>>> potential pitfall for interop issues. RFC9492 provides helpful directions 
>>> for us here.
>>> 
>>> a) This draft specifies FlexAlgo extensions, it is natural that Generic 
>>> Metric be advertised under ASLA TLV. No issues here.
>>> 
>>> b) This draft does not specify anything about use of generic metric in base 
>>> OSPF and as a reminder there is nothing like L-bit in OSPF encoding. 
>>> Therefore, it does not make sense to advertise Generic Metric outside of 
>>> ASLA and under the OSPFv2 Extended Link TLV or OSPFv3 Router Link TLV.
>>> 
>>> c) This draft does not specify anything about use of generic metric with 
>>> RSVP-TE/GMPLS. Therefore, it does not make sense to advertise Generic 
>>> Metric in the TE Opaque LSAs.
>>> 
>>> We can have specific documents that introduce (b) or (c) when there is a 
>>> proper specification.
>>> 
>>> <SH> Generic metric is a link attribute and can be used by other 
>>> applications apart from Flex-algo.
>>> 
>>> I don’t see a reason to not take code-points under other applicable LSAs.
>>> 
>>>  
>>> 
>>> KT> I disagree on this one. There is a reason why what is proposed in the 
>>> draft for ISIS is OK - due to the L-bit in ASLA, we need codepoints both 
>>> under ASLA and at the top level for FlexAlgo. There is no L-bit in OSPF and 
>>> therefore this does not apply. The code-points can be allocated when the 
>>> behavior is specified for those other LSAs and applications (beyond 
>>> FlexAlgo) in OSPF. We should not set the precedent for allocating 
>>> code-points for TLVs without any defined use or behavior.
>>> 
>>>  
>>> 
>>> <SH2> Early code points are taken and implementations underway for other 
>>> applications.
>>> 
>>>  
>>> 
>>> “Implementations MUST support sending and receiving generic metric
>>> 
>>> sub-TLV in ASLA encodings as well as in the TLV 22/extended link 
>>> LSA/TE-LSAs.
>>> 
>>> The usage of a generic metric by an individual application is subject to 
>>> the same
>>> 
>>> rules that apply to other link attributes defined in respective standards.”
>>> 
>>>  
>>> 
>>> The above text clarifies the use of generic metric by individual 
>>> application.
>>> 
>>>  
>>> 
>>> KT2> I am not sure this is sufficient. Let us take an example. How is the 
>>> Generic Metric TLV received in OSPFv2 TE Opaque LSA handled and what is it 
>>> used for?
>>> 
>>>  
>>> 
>>> <SH3> The text in the draft says the applications that make use of link 
>>> attributes from TE LSA will also use generic metric from TE-LSA. All 
>>> traditional TE applications like CSPF/RSVP make use of link-attributes from 
>>> TE-LSA. I don’t see the need to say anything beyond what has already been 
>>> said in the draft.
>>> 
>>>  
>>> 
>>> The Min Unidirectional Link Delay as advertised by sub-sub-TLV 12 of ASLA 
>>> sub-TLV [RFC8920 
>>> <https://urldefense.com/v3/__https:/www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html*RFC8920__;Iw!!NEt6yMaO-gk!DwOojW2YZ48IROz9qMyyh7uKj3rYC-09avEhFQtcPkvxJ5mKF5Cyy6qSVvDJ89s9DmAUVwsT_pgfmun5uDKc7A$>],
>>>  MUST be compared against the Maximum delay advertised in the FAEMD 
>>> sub-TLV. 
>>> 
>>> <SH> changed to “The Unidirectional Link Delay as advertised by sub-sub-TLV 
>>> 12”
>>> 
>>>  
>>> 
>>> KT> Perhaps my comment was not clear. The following text would be more 
>>> accurate:
>>> 
>>>  
>>> 
>>> The Min Delay value advertised via the Min/Max Unidirectional Link Delay 
>>> sub-TLV [RFC7471] of the ASLA sub-TLV [RFC8920 
>>> <https://urldefense.com/v3/__https:/www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html*RFC8920__;Iw!!NEt6yMaO-gk!HoQCxz15c5OoUVXjpmPpCU0N94Ex0cMuET6hFT8l6FE_kNkB58lpI-LSmXBUJvY4IdViL2mzTjVwvp4nyibk3A$>],
>>>  MUST be compared against the Maximum delay advertised in the FAEMD sub-TLV.
>>> 
>>> <SH2> I think there is a misunderstanding here. You are proposing to use 
>>> sub-tlv 13 where as the text in the draft clearly proposes to use sub-tlv 
>>> 12. This probably justifies why it is important to specify sub-tlv number
>>> 
>>> And not just name.
>>> 
>>>  
>>> 
>>> KT2> Well, that is what I am also trying to point out ... that the draft is 
>>> wrong :-) The one to use is 13  - please check below and let me know if I 
>>> am missing something. I also urge you to stick to using OSPF conventions of 
>>> using TLV names as opposed to the ISIS convention of using TLV numbers.
>>> 
>>>  
>>> 
>>> Refer: https://www.rfc-editor.org/rfc/rfc9350.html#section-5.2 
>>> <https://urldefense.com/v3/__https:/www.rfc-editor.org/rfc/rfc9350.html*section-5.2__;Iw!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvQO78JKxQ$>
>>>  ... look for IGP metric type 1
>>> 
>>> And then: https://www.rfc-editor.org/rfc/rfc7471#section-4.2 
>>> <https://urldefense.com/v3/__https:/www.rfc-editor.org/rfc/rfc7471*section-4.2__;Iw!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvSIQb9eeQ$>
>>>  and https://www.rfc-editor.org/rfc/rfc8920.html#section-14.1 
>>> <https://urldefense.com/v3/__https:/www.rfc-editor.org/rfc/rfc8920.html*section-14.1__;Iw!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvRWLiM03A$>
>>> 12
>>> 
>>> Unidirectional Link Delay
>>> 
>>> Y
>>> 
>>> [RFC9492 
>>> <https://urldefense.com/v3/__https:/www.iana.org/go/rfc9492__;!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvT7cfK2pA$>]
>>> 
>>> 13
>>> 
>>> Min/Max Unidirectional Link Delay
>>> 
>>> Y
>>> 
>>> [RFC9492 
>>> <https://urldefense.com/v3/__https:/www.iana.org/go/rfc9492__;!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvT7cfK2pA$>]
>>> 
>>>  
>>> 
>>> <SH3> Ok I got it. Will fix in -12 version
>>> 
>>>  
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 7) Regarding 
>>> https://www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html#section-6
>>>  
>>> <https://urldefense.com/v3/__https:/www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html*section-6__;Iw!!NEt6yMaO-gk!DwOojW2YZ48IROz9qMyyh7uKj3rYC-09avEhFQtcPkvxJ5mKF5Cyy6qSVvDJ89s9DmAUVwsT_pgfmumnzxX7UA$>,
>>>  it seems like we want to retain a numbering ordering of rules/sequence for 
>>> flex-algo as extension documents are introduced. Am I correct? If so, then 
>>> this document should formally "update" RFC9350 since it is changing the 
>>> "set of rules/sequence" for FlexAlgo computations. Further such extensions 
>>> will also need to keep updating the base spec similarly. I would suggest 
>>> that a full set of rules that is a union of what is in RFC9350 and rules 
>>> added by this draft are maintained in an Appendix section. Other documents 
>>> in the future can similarly maintain the latest set of rules.
>>> 
>>> <SH> This draft is adding 2 new rules at the end of existing rules. Its not 
>>> modifying or changing the order.
>>> 
>>> I don’t see what value it is going to add by repeating the set of rules in 
>>> Appendix.
>>> 
>>>  
>>> 
>>> KT> What happens when another FlexAlgo document adds more rules? What 
>>> happens when some FlexAlgo document wants to insert rules in the middle of 
>>> existing ones instead of appending at the end? My point is that if there is 
>>> a desire to establish a "live" set of rules in specific orders, then we 
>>> need to leave a trail of document "updates" on the base FlexAlgo that one 
>>> can refer to know how these "live set of rules" are getting "updated" by 
>>> this and future documents. I am thinking of this on lines similar to an 
>>> update for an FSM.
>>> 
>>> <SH2> It’s a matter of choice. For ex RFC 8029
>>> 
>>>             Has so many updates to the Rules but each update only lists the 
>>> changes.
>>> 
>>>  
>>> 
>>> KT2> I am not sure I follow and it would help if you can perhaps give an 
>>> example.
>>> 
>>>  
>>> 
>>>            I am fine with whatever WG decides to do.
>>> 
>>>             I want to hear if anyone in WG has an opinion on adding 
>>> Appendix.
>>> 
>>>  
>>> 
>>> KT2> Sure. My point is that this seems like an ordered set of rules that 
>>> are being updated by multiple documents (more to come). How does one keep 
>>> track of the "current" set of rules without some trail or each new(er) 
>>> document capturing the "latest" set?
>>> 
>>> <SH3> I don’t see any other opinions on mailing list. Will add appendix in 
>>> -12 with full set of rules.
>>> 
>>>  
>>> 
>>> Rgds
>>> 
>>> Shraddha
>>> 
>>>  
>>> 
>>> 
>>> Juniper Business Use Only
>>> 
>>> From: Ketan Talaulikar <ketant.i...@gmail.com 
>>> <mailto:ketant.i...@gmail.com>> 
>>> Sent: Saturday, April 27, 2024 11:44 AM
>>> To: Shraddha Hegde <shrad...@juniper.net <mailto:shrad...@juniper.net>>
>>> Cc: Acee Lindem <acee.lin...@gmail.com <mailto:acee.lin...@gmail.com>>; lsr 
>>> <lsr@ietf.org <mailto:lsr@ietf.org>>; 
>>> draft-ietf-lsr-flex-algo-bw-...@ietf.org 
>>> <mailto:draft-ietf-lsr-flex-algo-bw-...@ietf.org>
>>> Subject: Re: [Lsr] Working Group Last Call for "Flexible Algorithms: 
>>> Bandwidth, Delay, Metrics and Constraints" - 
>>> draft-ietf-lsr-flex-algo-bw-con-07
>>> 
>>>  
>>> 
>>> [External Email. Be cautious of content]
>>> 
>>>  
>>> 
>>> Hi Shraddha, 
>>> 
>>>  
>>> 
>>> Please check inline below with KT2.
>>> 
>>>  
>>> 
>>> On Mon, Apr 15, 2024 at 12:16 PM Shraddha Hegde <shrad...@juniper.net 
>>> <mailto:shrad...@juniper.net>> wrote:
>>> 
>>> Hi Ketan,
>>> 
>>>  
>>> 
>>> Thanks for reply.
>>> 
>>> Pls see inline..
>>> 
>>>  
>>> 
>>>  
>>> 
>>> Juniper Business Use Only
>>> 
>>> From: Ketan Talaulikar <ketant.i...@gmail.com 
>>> <mailto:ketant.i...@gmail.com>> 
>>> Sent: Monday, April 8, 2024 2:25 PM
>>> To: Shraddha Hegde <shrad...@juniper.net <mailto:shrad...@juniper.net>>
>>> Cc: Acee Lindem <acee.lin...@gmail.com <mailto:acee.lin...@gmail.com>>; lsr 
>>> <lsr@ietf.org <mailto:lsr@ietf.org>>; 
>>> draft-ietf-lsr-flex-algo-bw-...@ietf.org 
>>> <mailto:draft-ietf-lsr-flex-algo-bw-...@ietf.org>
>>> Subject: Re: [Lsr] Working Group Last Call for "Flexible Algorithms: 
>>> Bandwidth, Delay, Metrics and Constraints" - 
>>> draft-ietf-lsr-flex-algo-bw-con-07
>>> 
>>>  
>>> 
>>> [External Email. Be cautious of content]
>>> 
>>>  
>>> 
>>> Hi Shraddha,
>>> 
>>>  
>>> 
>>> Thanks for your responses. Please check inline below for clarifications 
>>> with KT.
>>> 
>>>  
>>> 
>>>  
>>> 
>>> On Thu, Apr 4, 2024 at 9:49 AM Shraddha Hegde <shrad...@juniper.net 
>>> <mailto:shrad...@juniper.net>> wrote:
>>> 
>>> Hi Ketan,
>>> 
>>>  
>>> 
>>> Thanks for the review and comments.
>>> 
>>> Pls see inline for replies.
>>> 
>>>  
>>> 
>>>  
>>> 
>>> Juniper Business Use Only
>>> 
>>> From: Ketan Talaulikar <ketant.i...@gmail.com 
>>> <mailto:ketant.i...@gmail.com>> 
>>> Sent: Thursday, March 21, 2024 10:07 PM
>>> To: Acee Lindem <acee.lin...@gmail.com <mailto:acee.lin...@gmail.com>>
>>> Cc: lsr <lsr@ietf.org <mailto:lsr@ietf.org>>; 
>>> draft-ietf-lsr-flex-algo-bw-...@ietf.org 
>>> <mailto:draft-ietf-lsr-flex-algo-bw-...@ietf.org>
>>> Subject: Re: [Lsr] Working Group Last Call for "Flexible Algorithms: 
>>> Bandwidth, Delay, Metrics and Constraints" - 
>>> draft-ietf-lsr-flex-algo-bw-con-07
>>> 
>>>  
>>> 
>>> [External Email. Be cautious of content]
>>> 
>>>  
>>> 
>>> Hi All,
>>> 
>>>  
>>> 
>>> I have reviewed this document and believe it needs some further work before 
>>> publication. 
>>> 
>>>  
>>> 
>>> I am sharing my comments below: 
>>> 
>>>  
>>> 
>>> 1) There is the following text in sec 2.1 and 2.2 for Generic Metric.
>>> 
>>>  
>>> 
>>> A metric value of 0xFFFFFF is considered as maximum link metric and a link 
>>> having this metric value MUST NOT be used during Flex-algorithm 
>>> calculations [RFC9350 
>>> <https://urldefense.com/v3/__https:/www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html*RFC9350__;Iw!!NEt6yMaO-gk!DwOojW2YZ48IROz9qMyyh7uKj3rYC-09avEhFQtcPkvxJ5mKF5Cyy6qSVvDJ89s9DmAUVwsT_pgfmuk-veyTXw$>].
>>>  The link with maximum generic metric value is not available for the use of 
>>> Flexible Algorithms but is availble for other use cases.
>>> 
>>>  
>>> 
>>> I believe the FlexAlgo reference here is to 
>>> https://www.rfc-editor.org/rfc/rfc9350.html#name-max-metric-consideration 
>>> <https://urldefense.com/v3/__https:/www.rfc-editor.org/rfc/rfc9350.html*name-max-metric-consideration__;Iw!!NEt6yMaO-gk!DwOojW2YZ48IROz9qMyyh7uKj3rYC-09avEhFQtcPkvxJ5mKF5Cyy6qSVvDJ89s9DmAUVwsT_pgfmumv0_0Zeg$>
>>>  
>>> 
>>>  
>>> 
>>> But the above text does not align with the RFC9350. If a link is to be made 
>>> unavailable for FlexAlgos operating with a specific Generic Metric, then 
>>> the way to do that is to omit that specific Generic Metric TLV from the 
>>> ASLA for flex-algo application. The same would apply for other applications 
>>> - just omit the metric. Why do we need a special MAX-LINK-METRIC value for 
>>> generic metric given that it is a new thing we are introducing?
>>> 
>>>  
>>> 
>>> <SH> I see what you are saying. Text is updated as below for ISIS and 
>>> similar for OSPF.
>>> 
>>> “A metric value of
>>> 
>>>    0xFFFFFF is considered as maximum link metric and a link having
>>> 
>>>    this metric value MUST be used during Flex-algorithm calculations
>>> 
>>>    as a last resort link as described in sec 15.3 of RFC[9350]
>>> 
>>>  
>>> 
>>> KT> Thanks - that works. Perhaps also clarify that to make the link 
>>> unusable by FlexAlgo using that generic metric, the advertisement of the 
>>> particular generic metric can be skipped.
>>> 
>>> <SH2> ok
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 2) This comment is specific to OSPF given the encoding differences it has 
>>> with ISIS. Section 2.2 allows for Generic Metric TLV to be used in too many 
>>> places without clear specification of what it is used for - this is a 
>>> potential pitfall for interop issues. RFC9492 provides helpful directions 
>>> for us here.
>>> 
>>> a) This draft specifies FlexAlgo extensions, it is natural that Generic 
>>> Metric be advertised under ASLA TLV. No issues here.
>>> 
>>> b) This draft does not specify anything about use of generic metric in base 
>>> OSPF and as a reminder there is nothing like L-bit in OSPF encoding. 
>>> Therefore, it does not make sense to advertise Generic Metric outside of 
>>> ASLA and under the OSPFv2 Extended Link TLV or OSPFv3 Router Link TLV.
>>> 
>>> c) This draft does not specify anything about use of generic metric with 
>>> RSVP-TE/GMPLS. Therefore, it does not make sense to advertise Generic 
>>> Metric in the TE Opaque LSAs.
>>> 
>>> We can have specific documents that introduce (b) or (c) when there is a 
>>> proper specification.
>>> 
>>> <SH> Generic metric is a link attribute and can be used by other 
>>> applications apart from Flex-algo.
>>> 
>>> I don’t see a reason to not take code-points under other applicable LSAs.
>>> 
>>>  
>>> 
>>> KT> I disagree on this one. There is a reason why what is proposed in the 
>>> draft for ISIS is OK - due to the L-bit in ASLA, we need codepoints both 
>>> under ASLA and at the top level for FlexAlgo. There is no L-bit in OSPF and 
>>> therefore this does not apply. The code-points can be allocated when the 
>>> behavior is specified for those other LSAs and applications (beyond 
>>> FlexAlgo) in OSPF. We should not set the precedent for allocating 
>>> code-points for TLVs without any defined use or behavior.
>>> 
>>>  
>>> 
>>> <SH2> Early code points are taken and implementations underway for other 
>>> applications.
>>> 
>>>  
>>> 
>>> “Implementations MUST support sending and receiving generic metric
>>> 
>>> sub-TLV in ASLA encodings as well as in the TLV 22/extended link 
>>> LSA/TE-LSAs.
>>> 
>>> The usage of a generic metric by an individual application is subject to 
>>> the same
>>> 
>>> rules that apply to other link attributes defined in respective standards.”
>>> 
>>>  
>>> 
>>> The above text clarifies the use of generic metric by individual 
>>> application.
>>> 
>>>  
>>> 
>>> KT2> I am not sure this is sufficient. Let us take an example. How is the 
>>> Generic Metric TLV received in OSPFv2 TE Opaque LSA handled and what is it 
>>> used for?
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 3) Please introduce a reserved field to pad the OSPF FAEMD sub-TLV to a 4 
>>> octet boundary as is the convention in OSPF - 
>>> https://www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html#section-3.2.2
>>>  
>>> <https://urldefense.com/v3/__https:/www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html*section-3.2.2__;Iw!!NEt6yMaO-gk!DwOojW2YZ48IROz9qMyyh7uKj3rYC-09avEhFQtcPkvxJ5mKF5Cyy6qSVvDJ89s9DmAUVwsT_pgfmunYcymQgw$>
>>> <SH> OK
>>> 
>>>  
>>> 
>>> KT> Thanks.
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 4) In section 3.2.2 there is the following text for OSPF. Could you please 
>>> use the TLV/sub-TLV name? OSPF folks are not good at remembering numbers ;-)
>>> 
>>>  
>>> 
>>> The Min Unidirectional Link Delay as advertised by sub-sub-TLV 12 of ASLA 
>>> sub-TLV [RFC8920 
>>> <https://urldefense.com/v3/__https:/www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html*RFC8920__;Iw!!NEt6yMaO-gk!DwOojW2YZ48IROz9qMyyh7uKj3rYC-09avEhFQtcPkvxJ5mKF5Cyy6qSVvDJ89s9DmAUVwsT_pgfmun5uDKc7A$>],
>>>  MUST be compared against the Maximum delay advertised in the FAEMD 
>>> sub-TLV. 
>>> 
>>> <SH> changed to “The Unidirectional Link Delay as advertised by sub-sub-TLV 
>>> 12”
>>> 
>>>  
>>> 
>>> KT> Perhaps my comment was not clear. The following text would be more 
>>> accurate:
>>> 
>>>  
>>> 
>>> The Min Delay value advertised via the Min/Max Unidirectional Link Delay 
>>> sub-TLV [RFC7471] of the ASLA sub-TLV [RFC8920 
>>> <https://urldefense.com/v3/__https:/www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html*RFC8920__;Iw!!NEt6yMaO-gk!HoQCxz15c5OoUVXjpmPpCU0N94Ex0cMuET6hFT8l6FE_kNkB58lpI-LSmXBUJvY4IdViL2mzTjVwvp4nyibk3A$>],
>>>  MUST be compared against the Maximum delay advertised in the FAEMD sub-TLV.
>>> 
>>> <SH2> I think there is a misunderstanding here. You are proposing to use 
>>> sub-tlv 13 where as the text in the draft clearly proposes to use sub-tlv 
>>> 12. This probably justifies why it is important to specify sub-tlv number
>>> 
>>> And not just name.
>>> 
>>>  
>>> 
>>> KT2> Well, that is what I am also trying to point out ... that the draft is 
>>> wrong :-) The one to use is 13  - please check below and let me know if I 
>>> am missing something. I also urge you to stick to using OSPF conventions of 
>>> using TLV names as opposed to the ISIS convention of using TLV numbers.
>>> 
>>>  
>>> 
>>> Refer: https://www.rfc-editor.org/rfc/rfc9350.html#section-5.2 
>>> <https://urldefense.com/v3/__https:/www.rfc-editor.org/rfc/rfc9350.html*section-5.2__;Iw!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvQO78JKxQ$>
>>>  ... look for IGP metric type 1
>>> 
>>> And then: https://www.rfc-editor.org/rfc/rfc7471#section-4.2 
>>> <https://urldefense.com/v3/__https:/www.rfc-editor.org/rfc/rfc7471*section-4.2__;Iw!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvSIQb9eeQ$>
>>>  and https://www.rfc-editor.org/rfc/rfc8920.html#section-14.1 
>>> <https://urldefense.com/v3/__https:/www.rfc-editor.org/rfc/rfc8920.html*section-14.1__;Iw!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvRWLiM03A$>
>>> 12
>>> 
>>> Unidirectional Link Delay
>>> 
>>> Y
>>> 
>>> [RFC9492 
>>> <https://urldefense.com/v3/__https:/www.iana.org/go/rfc9492__;!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvT7cfK2pA$>]
>>> 
>>> 13
>>> 
>>> Min/Max Unidirectional Link Delay
>>> 
>>> Y
>>> 
>>> [RFC9492 
>>> <https://urldefense.com/v3/__https:/www.iana.org/go/rfc9492__;!!NEt6yMaO-gk!CCtWq3oQk0cXbjdWmHoJomutLcmgPIHyX5LjNSahUulgW61QgLgqXr_Kj74WrmzBmvkbwwnzm_SiyvT7cfK2pA$>]
>>> 
>>>  
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 5) Do we want to call out that the reference bandwidth approach requires a 
>>> router to compute and maintain a per link per algo bandwidth metric for 
>>> every link in that algo topology. It may not be very obvious to some.
>>> 
>>> <SH> updated as below
>>> 
>>> “Advertising
>>> 
>>>    the reference bandwidth in the FAD constraints allows the metric
>>> 
>>>    computation to be done on every node for each link.
>>> 
>>>    The metric is computed using reference bandwidth and the advertised link 
>>> bandwidth.
>>> 
>>>    Centralized control of this
>>> 
>>>    reference bandwidth simplifies management in the case that the
>>> 
>>>    reference bandwidth changes”
>>> 
>>>  
>>> 
>>> KT> The above text is not really needed IMHO. My point was more about the 
>>> implementation detail - for the flexalgo computation, we need to maintain 
>>> this info on a per link per algo topology basis in the link-state data 
>>> store used for path computation. I will leave it to the authors if this is 
>>> needed or is obviously clear to implementers.
>>> 
>>> <SH2> I don’t see the need to add implementation specific details.
>>> 
>>>  
>>> 
>>> KT2> OK - I leave it to you. 
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 6) There are a lot of procedures which are common to both OSPF and ISIS and 
>>> are repeated in each section instead of a common section. It would be 
>>> easier (and avoid errors) if there was some consolidation. 
>>> https://www.rfc-editor.org/rfc/rfc9350.html#section-5 
>>> <https://urldefense.com/v3/__https:/www.rfc-editor.org/rfc/rfc9350.html*section-5__;Iw!!NEt6yMaO-gk!DwOojW2YZ48IROz9qMyyh7uKj3rYC-09avEhFQtcPkvxJ5mKF5Cyy6qSVvDJ89s9DmAUVwsT_pgfmumpoQRYAA$>
>>>  provides a good reference for such an organization of text.
>>> 
>>> <SH> There is repetition in some cases but its not much so it seems to me 
>>> leaving it as is for clarity may be better.
>>> 
>>>  
>>> 
>>> KT> This is an editorial comment so I leave it to the authors. My concern 
>>> is that great care/diligence is required through the rest of the 
>>> publication process to ensure that when anything is changed or updated for 
>>> one IGP, it is done appropriately for the other as well - it may be 
>>> copy/paste case when the change is IGP agnostic but may need careful 
>>> consideration when related to the specific IGP mechanics.
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 7) Regarding 
>>> https://www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html#section-6
>>>  
>>> <https://urldefense.com/v3/__https:/www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-bw-con-08.html*section-6__;Iw!!NEt6yMaO-gk!DwOojW2YZ48IROz9qMyyh7uKj3rYC-09avEhFQtcPkvxJ5mKF5Cyy6qSVvDJ89s9DmAUVwsT_pgfmumnzxX7UA$>,
>>>  it seems like we want to retain a numbering ordering of rules/sequence for 
>>> flex-algo as extension documents are introduced. Am I correct? If so, then 
>>> this document should formally "update" RFC9350 since it is changing the 
>>> "set of rules/sequence" for FlexAlgo computations. Further such extensions 
>>> will also need to keep updating the base spec similarly. I would suggest 
>>> that a full set of rules that is a union of what is in RFC9350 and rules 
>>> added by this draft are maintained in an Appendix section. Other documents 
>>> in the future can similarly maintain the latest set of rules.
>>> 
>>> <SH> This draft is adding 2 new rules at the end of existing rules. Its not 
>>> modifying or changing the order.
>>> 
>>> I don’t see what value it is going to add by repeating the set of rules in 
>>> Appendix.
>>> 
>>>  
>>> 
>>> KT> What happens when another FlexAlgo document adds more rules? What 
>>> happens when some FlexAlgo document wants to insert rules in the middle of 
>>> existing ones instead of appending at the end? My point is that if there is 
>>> a desire to establish a "live" set of rules in specific orders, then we 
>>> need to leave a trail of document "updates" on the base FlexAlgo that one 
>>> can refer to know how these "live set of rules" are getting "updated" by 
>>> this and future documents. I am thinking of this on lines similar to an 
>>> update for an FSM.
>>> 
>>> <SH2> It’s a matter of choice. For ex RFC 8029
>>> 
>>>             Has so many updates to the Rules but each update only lists the 
>>> changes.
>>> 
>>>  
>>> 
>>> KT2> I am not sure I follow and it would help if you can perhaps give an 
>>> example.
>>> 
>>>  
>>> 
>>>            I am fine with whatever WG decides to do.
>>> 
>>>             I want to hear if anyone in WG has an opinion on adding 
>>> Appendix.
>>> 
>>>  
>>> 
>>> KT2> Sure. My point is that this seems like an ordered set of rules that 
>>> are being updated by multiple documents (more to come). How does one keep 
>>> track of the "current" set of rules without some trail or each new(er) 
>>> document capturing the "latest" set?
>>> 
>>>  
>>> 
>>> Thanks,
>>> 
>>> Ketan
>>> 
>>>  
>>> 
>>>  
>>> 
>>> Thanks,
>>> 
>>> Ketan
>>> 
>>>  
>>> 
>>>  
>>> 
>>>  
>>> 
>>> 8) Please fix idnits warnings - some are related to obsolete references 
>>> while others are related to formatting. There are also some 
>>> spelling/grammar errors.
>>> 
>>> <SH> ok
>>> 
>>>  
>>> 
>>> Thanks,
>>> 
>>> Ketan
>>> 
>>>  
>>> 
>>>  
>>> 
>>> On Tue, Feb 20, 2024 at 3:56 AM Acee Lindem <acee.lin...@gmail.com 
>>> <mailto:acee.lin...@gmail.com>> wrote:
>>> 
>>> 
>>> This starts the Working Group Last call for 
>>> draft-ietf-lsr-flex-algo-bw-con-07. At least some of the flex algorithm 
>>> enhancements described in the document have been implemented. 
>>> 
>>>  Please send your support or objection to this before March 5th, 2024. 
>>> 
>>> Thanks,
>>> Acee
>>> _______________________________________________
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