Thank you Dhruv.

We have posted the updated draft (revision 20).

Regards,
Rakesh

The IETF datatracker status page for this Internet-Draft is:
https://datatracker.ietf.org/doc/draft-ietf-pce-sr-bidir-path/

There is also an HTMLized version available at:
https://datatracker.ietf.org/doc/html/draft-ietf-pce-sr-bidir-path-20

A diff from the previous version is available at:
https://author-tools.ietf.org/iddiff?url2=draft-ietf-pce-sr-bidir-path-20



On Thu, Jan 8, 2026 at 4:36 AM Dhruv Dhody <[email protected]> wrote:

> Hi Rakesh,
>
> Thanks for quickly handling the comments and sharing the update. Please
> post it and I will ship the draft to our AD.
>
> Thanks!
> Dhruv
>
> On Thu, Jan 8, 2026 at 5:07 AM Rakesh Gandhi <[email protected]>
> wrote:
>
>> Hi Dhruv,
>>
>> Happy New Year!
>>
>> Thank you for the thorough review of the draft.
>>
>> Attaching work in progress updates to the draft that address your
>> comments.
>>
>> Please see replies inline with <RG>...
>>
>> On Wed, Jan 7, 2026 at 6:44 AM Dhruv Dhody <[email protected]> wrote:
>>
>>> Hi Authors,
>>>
>>> I have finished the shepherd review of the draft. I have noted some
>>> minor comments and nits that should be fixed before sending the draft to
>>> our AD.
>>>
>>> ## Minor
>>>
>>> * Introduction (and abstract) mentions ‘tunneling paradigms’; note that
>>> RFC 8402 does not use that term. Suggest removing it.
>>>
>>
>> <RG> Fixed.
>>
>>
>>>
>>> * Section 1, “This allows both endpoint ingress nodes to be aware of the
>>> SR paths in both directions, including their status and all other
>>> path-related information”; don't we need to remove the text about status
>>> and path-related information based on the recent changes in the draft?
>>>
>>
>> <RG> Fixed.
>>
>>
>>>
>>> * Section 3, should RFC 9059 (which is about RSVP-TE only) be listed?
>>>
>>
>> <RG> Removed.
>>
>>
>>>
>>> * Section 3.1, Step 1 is unclear, as the first and second sentences use
>>> 'MAY' and 'MUST' with essentially the same condition, which makes it
>>> difficult to understand under what circumstances each applies.
>>>
>>
>> <RG> Fixed to use non-normative language as it uses the existing RFC
>> messages. Does that help?
>>
>>
>>> Mentioning PLSP-ID in Step 2 is unnecessary since the reverse-side LSP
>>> creation is removed, and PLSP-ID allocation follows normal PCEP behavior
>>> and does not need to be restated here, nor does it need to be expressed as
>>> a normative MUST.
>>>
>>
>> <RG> It would be good to say what happens on PCC.
>> <RG> Fixed to use non-normative language as it uses the existing RFC
>> messages.
>>
>>
>>
>>> In Figure 1, can we explicitly state that F1==R1 and F2==R2, as well as
>>> at PCC, the association #1 has a single LSP in the group.
>>>
>>
>> <RG> Added.
>>
>>
>>>
>>> * Section 3.2, here as well, step 1 MAY and MUST use is unclear to me.
>>> What is the change of association group now? And the above comments apply
>>> here as well.
>>>
>>
>> <RG> Updated as above.
>>
>>
>>>
>>> * Section 4.1, Can we reuse “5 | Double-Sided Bidirectional LSP
>>> Association | RFC 9059” instead of defining a new association type? Any
>>> behavior change can be handled via PST? If a new association type is needed
>>> than it should be justified.
>>>
>>
>> <RG> The concept is different for RSVP-TE, where the association of the
>> reverse LSPs happen on the PCCs via signalling, whereas for SR-TE, the
>> association happens on PCE and PCC is just given the reverse EROs, there is
>> no instantiation of reverse SR LSPs on PCCs.
>>
>> <RG> Overloading the type with different procedures based on PST would be
>> kludgy, IMO.
>>
>> <RG> Association type has a range of 64K values available; it is not a
>> scarce resource and not worth saving one value.
>>
>>
>>
>>> Remove MUST in the 3rd paragraph, when restating behaviour from the
>>> published RFC.
>>>
>>
>> <RG> Removed the paragraph as it is just repeating the existing procedure.
>>
>>
>>> * Section 4.1, we need better error handling. For the first bullet,
>>> apart from not sending associated reverse SR path EROs to PCC, we need to
>>> raise an alarm and log it. For the second, we have an existing error “19:
>>> Endpoint mismatch in the association group” from 9059 that could be reused?
>>>
>>
>> <RG> Added.
>>
>>
>>>
>>> * Section 4.2, for R flag, we should explicitly state that it MUST NOT
>>> be set and if received, it MUST be ignored"
>>>
>>
>> <RG> Added.
>>
>>
>>>
>>> * Section 5.4, it sounds like you are saying PSID can be used instead of
>>> association. I would also suggest not mentioning any details such as
>>> PATH-SEGMENT TLV, especially since no change is being made to it.
>>>
>>
>> <RG> Updated.
>>
>>
>>>
>>> * Section 5.5, can we simplify this -
>>>
>>> OLD:
>>> [RFC9059] in Section 5.7, defines a PCErr message for the Path Setup
>>> Type (PST) of ‘0: Path is set up using the RSVP-TE signaling protocol’
>>> [RFC8408]. The PST for SR path is set to ‘1: Traffic-engineering path is
>>> set up using Segment Routing’ [RFC8664] or ‘3: Traffic engineering path is
>>> set up using SRv6’ [RFC9603]. If a PCEP speaker receives an unsupported PST
>>> value for the ‘Double-Sided Bidirectional with Reverse LSP Association’,
>>> the PCE speaker MUST return a PCErr message with Error-Type = 26
>>> (Association Error) and Error-value = ‘16: Path Setup Type not supported’
>>> [RFC9059].
>>> NEW:
>>> The PST for SR path is either ‘1: Traffic-engineering path is set up
>>> using Segment Routing’ [RFC8664] or ‘3: Traffic engineering path is set up
>>> using SRv6’ [RFC9603]. If a PCEP speaker receives a non-SR PST value for
>>> the ‘Double-Sided Bidirectional with Reverse LSP Association’, the PCE
>>> speaker MUST return a PCErr message with Error-Type = 26 (Association
>>> Error) and Error-value = ‘16: Path Setup Type not supported’ [RFC9059].
>>> END
>>>
>>
>> <RG> Updated.
>>
>>
>>>
>>> * Section 7, consider adding this - “as per the recommendations and best
>>> current practices in [RFC9325]”
>>>
>>
>> <RG> Added.
>>
>>
>>>
>>> * Section 8, avoid repetition of references in 8.1, 8.3, 8.4, and 8.6
>>> since you have already added text in section 8. I think you can also add a
>>> reference to RFC 8697 for association-related stuff.
>>>
>>
>> <RG> Updated.
>>
>>
>>>
>>> * Section 10.2, RFC 8253 should be a normative reference.
>>>
>>
>> <RG> Updated.
>>
>>
>>>
>>> ## Nits
>>>
>>> * Let me suggest a rewrite for your abstract to make it flow better -
>>>
>>> ````
>>> The Path Computation Element Communication Protocol (PCEP) provides
>>> mechanisms for Path Computation Elements (PCEs) to perform path
>>> computations in response to Path Computation Clients (PCCs) requests.
>>> Segment Routing (SR) can be used to steer packets through a network
>>> employing the source routing paradigm. Stateful PCEP extensions for SR,
>>> allow a PCE to maintain state and to control and initiate SR Traffic
>>> Engineering (TE) paths.
>>>
>>> PCEP supports grouping of two unidirectional MPLS-TE Label Switched
>>> Paths (LSPs), signalled via RSVP-TE, using association. This document
>>> defines PCEP extensions for grouping two unidirectional SR paths (one in
>>> each direction in the network) into a single associated bidirectional SR
>>> path. The mechanisms defined in this document are applicable to both
>>> stateless and stateful PCEs for PCE-initiated and PCC-initiated LSPs.
>>> ````
>>>
>>>
>> <RG> Updated.
>>
>>
>>> * Section 1, s/The RSVP-TE signals the forward LSP to the egress
>>> nodes/The forward LSPs to the egress nodes are signaled using RSVP-TE/
>>>
>>
>> <RG> Updated.
>>
>>
>>>
>>> * Section 1, s/learn the reverse LSPs/learn the corresponding reverse
>>> LSPs/
>>>
>>
>> <RG> Updated.
>>
>>
>>>
>>> * Section 1, this sentence needs rephrasing - “An SR Policy contains one
>>> or more Candidate Paths (CPs) [RFC9256] from which one or more Candidate
>>> Paths can be computed via PCE”, maybe - “An SR Policy contains one or more
>>> Candidate Paths (CPs) [RFC9256], which may be computed by a PCE”. Also,
>>> “When a Candidate Path is computed by the PCE, it means that the PCE
>>> computed all SLs of that Candidate Path”, can this be - “When a Candidate
>>> Path is computed by the PCE, the PCE computes one or more Segment Lists for
>>> that Candidate Path”.
>>>
>>
>> <RG> Updated.
>>
>>
>>>
>>> * Section 4.1, s/PCE peers/PCEP peers/ or just say PCCs in this context?
>>>
>>
>> <RG> Updated.
>>
>> Again, many thanks for the great review and suggestions.
>>
>> Regards,
>> Rakesh (for authors)
>>
>>
>>
>>
>>
>>> Thanks!
>>> Dhruv
>>> _______________________________________________
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>>>
>>
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