Hi Ron, As an operator, I share the concern that energy-saving capabilities cannot be viewed solely through the lens of routing extensions.
While I understand the argument that the current LSR and TEAS drafts focus only on the path placement component and not on sleep management, operators ultimately deploy a complete solution rather than individual protocol components. The operational value of the proposed mechanisms depends on how routing decisions, device capabilities, power-state models, management systems, and automation frameworks work together. Hence, one of the most important requirements is consistency across planes and across working groups. We should avoid a situation where GREEN defines one set of assumptions and abstractions while routing extensions evolve independently with a different interpretation of power-saving behavior. Such divergence would increase implementation complexity and complicate interoperability across vendors. For operators, the key question is not whether a function is located in the routing plane, the management plane, or a centralized controller. The key question is whether all components can be deployed and operated coherently as part of the same energy-efficiency strategy - and if they use the same semantic. Having to do transformations in a middleware to normalize the output is a burden for operational use, too. Therefore, I support stronger coordination between GREEN, TEAS, and LSR to ensure that the resulting specifications form a consistent operational framework. Best regards, Nils. Deutsche Telekom Technik GmbH E-Mail: [email protected]<mailto:[email protected]> www.telekom.de<http://www.telekom.de/> [Ein Bild, das Schrift, Grafiken, Grafikdesign, Text enthalt. Automatisch generierte Beschreibung] [StandortMunsterBanner] Die gesetzlichen Pflichtangaben finden Sie unter: www.telekom.de/pflichtangaben-dttechnik<http://www.telekom.de/pflichtangaben-dttechnik> ----------------------------- On 9/1/2026 4:08 AM, Chengen(GenChen) wrote: Hi Ron, Thank you for the response. I adjusted the cc list a bit to avoid potential receiving duplications. The “decoupling” argument mentioned here misses the architectural dependency: PCPPS and IGP extensions define what to advertise, but sleep management defines why and when. You cannot specify IGP extensions without knowing the power state model, component capabilities, and wake/sleep criteria. Again, operators won’t reconcile independently defined power-saving mechanisms. Therefore, adopt the LSR/TEAS IGP extensions/PCPPS drafts only after the GREEN framework and YANG data models mature and the mapping to routing advertisements is explicitly validated. Deferring now avoids rework and ensures operational coherence. BR, Genchen From: Bonica, Ron <[email protected]><mailto:[email protected]> Sent: 2026年8月29日 2:43 To: Aijun Wang <[email protected]><mailto:[email protected]>; 'Bonica, Ron' <[email protected]><mailto:[email protected]>; 'Christian Hopps' <[email protected]><mailto:[email protected]>; [email protected]<mailto:[email protected]> Cc: [email protected]<mailto:[email protected]>; [email protected]<mailto:[email protected]>; [email protected]<mailto:[email protected]> Subject: [Lsr] Re: WG adoption call for draft-many-lsr-power-group-03 (Ends 2026-08-30) Aijun, GenChen, Benoit, JinMing Each of you have expressed concern regarding a distributed approach to the Power Conserving Path Placement Strategy (PCPPS). The following is a response. A Power Conservation Strategy includes many components. First among them is the Path Placement Component. The Path Placement Component concentrates traffic onto relatively few network resources during periods of low demand and redistributes traffic during periods of high demand. It *does not* power interfaces up and down. Its only function is path computation. When it computes paths, it optimizes for energy efficiency, leaving some network resources idle or nearly idle. Another component is the Sleep Management Component. The Sleep Management Component is configured with criteria that must be satisfied before a network resource is powered down. It monitors network resources and powers them down when they satisfy the configured criteria. It also powers them up again when the power up criteria are satisfied. The Power Placement Component and Sleep Management Component are decoupled from one another. In the simplest case, one could run a Path Placement Component without a Sleep Management Component. (Although I can't imagine why). One could also run a Sleep Management Component without a Path Placement Component. In some networks, and for some power down criteria, this makes sense. In a more complex case, the Sleep Management component may require information from the Path Placement component to determine if an interface satisfies the power-up/power-down criteria. For example, the Sleep Management algorithm may prevent interfaces that support LSPs from being powered down. Draft-many-teas-power-steering and draft-many-lsr-power-groups describe the Path Placement Component. They *do not* describe the Sleep Management function. This is beyond their scope. Many of your comments address the Sleep Management function. For example: 1. You will not find an instruction to power an interface up or down in either of the current drafts 1. The problem of oscillation due to frequent power-up/power-down events is beyond the scope of the current documents, because they do not power network resources up or down. Finally, regarding the question of distributed versus centralized implementation..... Path Placement Strategies rely on CSPF and the CSPF relies on the LSDB/TED. Each node must maintain an identical LSDB copy. In the past, we have populated the LSDB/TED in a distributed manner, using an IGP, or in a centralized manner, using a PCE and BGP-LS. Both approaches work. Some customers prefer one while other customers prefer the other. The Power Conserving Path Placement Strategy is no different from legacy path placement strategies. There is no reason why it should be limited to one approach or the other. Ron ________________________________ From: Aijun Wang <[email protected]<mailto:[email protected]>> Sent: Tuesday, August 25, 2026 11:09 PM To: 'Bonica, Ron' <[email protected]<mailto:[email protected]>>; 'Christian Hopps' <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>> Cc: [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>> Subject: RE: [Lsr] Re: WG adoption call for draft-many-lsr-power-group-03 (Ends 2026-08-30) Hi, Ron: Since the TEAS WG has yet start the adoption call of draft-many-teas-power-group.(They are preparing for it now/IPR call), I would still suggest that we wait the conclusion of adoption call of the base document. And I think you have noticed, there is argument for the necessary of the distributed solution, given it can’t finish the overall power save aim itself(need information or control capabilities from the management plane), and overlap with the capabilities of management plane. Until now, I don’t see the promise of the distributed solution, only the confusion of these newly introduced capricious TLVs and their usages. Or, would you like to introduce the necessary, indispensable or even the benefits of the distributed solution? Some detail replies inline below. Best Regards Aijun Wang China Telecom From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Bonica, Ron Sent: Wednesday, August 26, 2026 8:07 AM To: Aijun Wang <[email protected]<mailto:[email protected]>>; 'Christian Hopps' <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> Cc: [email protected]<mailto:[email protected]>; [email protected]<mailto:[email protected]>; [email protected]<mailto:[email protected]> Subject: [Lsr] Re: WG adoption call for draft-many-lsr-power-group-03 (Ends 2026-08-30) Hi Ajun, Thanks for the review. Response inline See [rb] Ron ________________________________ From: Aijun Wang <[email protected]<mailto:[email protected]>> Sent: Monday, August 24, 2026 10:23 PM To: 'Christian Hopps' <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>> Cc: [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>> Subject: RE: [Lsr] Re: WG adoption call for draft-many-lsr-power-group-03 (Ends 2026-08-30) 【Correct one typo: 】 I do not support its adoption. -----Original Message----- From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Aijun Wang Sent: Tuesday, August 25, 2026 10:19 AM To: 'Christian Hopps' <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> Cc: [email protected]<mailto:[email protected]>; [email protected]<mailto:[email protected]>; [email protected]<mailto:[email protected]> Subject: [Lsr] Re: WG adoption call for draft-many-lsr-power-group-03 (Ends 2026-08-30) Hi, All: I do not support is adoption. The reason are the followings: 1) The base document, https://urldefense.com/v3/__https://datatracker.ietf.org/doc/draft-many-teas-power-steering/__;!!NpxR!iPWTa_HdgTs4cfKq-wRonK1P2gTSQHdnS6G14eA4oW_y_OIb6VUvnFZwy4DJlK0_xuExEoZ2KnHSBwyHIjSsao3c$<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/draft-many-teas-power-steering/__;!!NpxR!iPWTa_HdgTs4cfKq-wRonK1P2gTSQHdnS6G14eA4oW_y_OIb6VUvnFZwy4DJlK0_xuExEoZ2KnHSBwyHIjSsao3c$> , has not been adopted as the TEAS WG document, it is too early to determine whether the IGP protocol extension is necessary or not. [rb] I think that Gunther addressed this issue. In any event, the TEAS WG is currently having a call for adoption on draft-many-teas-power-group. [WAJ] Let’s wait the conclusion of the adoption call of the base document, then the necessary of this distributed solution. 2) There is no any description, or argument to describe the reason that accomplish the power saving via the distributed IGP protocol and the challenge for the network operation etc. when comparing with the solution solely via the management plane(NETCONT/YANG etc.) [rb] The current drafts describe a distributed Power Conserving Path Placement Solution. They do not preclude a centralized solution. Because we do not preclude a centralized solution, we don't feel the need to argue against one. [WAJ] I don’t see the benefits, or the indispensable necessary of such distributed solution. 3) Considering the mentioned interfaces can only be switched on/off via the management, I am wondering why bother IGP to accomplish the path calculation work then? [rb] Are you sure that interfaces can only be switched on/off via a network management interface? Is it possible that the platform might offer an API through which an interface can be switched on/off? Might that API be made available to multiple network management applications (e.g., CLI, NETCONF)? Might that API also be made available to a local application that monitors interface utilization and powers interface on/off as needed? [WAJ] These are all possible, but currently there are no on/off signal communicated via the IGP protocol, then it must depend on other ways to accomplish the power save aim. Or, will you add some mechanism in your proposal later? Are you sure that the IGP does the path calculation work? According to draft-many-teas-power-steering, CSPF does the path calculation work. It uses the PCPPS metric to do so. It uses the TLVs described in draft-many-lsr-power-group to calculate the PCPPS metric. [WAJ] If the flooding of these TLVs is not let IGP does the path calculation work, then the necessary of such flooding became more unnecessary: The PCE know the services requirements, the PCE can collect the network conditions, the PCE can calculate the necessary topology/bandwidth/interfaces on/off, then why let the IGP do extraordinary work? 4) Given the discussions for the encoding of proposed TLVs, and the authors' responses for the updating them later, which are all non-trivial modifications, it's better to postpone to its adoption. [rb] This is a procedural issue, to be addressed by the chairs. Typically, at the end of a call for adoption, authors are given a chance to produce a new version of the draft that addresses issues raided during the call for adoption. [WAJ] The core contents of this LSR draft are the definition of these TLVs, If they have not been solid, what’s the value, and legitimacy of the adoption call? 5) The document defines only some TLVs and there is no any procedures to describe how to utilize them, how to coordinate with other existing TLVs/sub-TLVs/Flooding mechanism etc., it will be difficult for other vendors to implement and will influence future interoperability. [rb] Which TLVs are missing? As per draft-many-teas-power-steering, these TLVs are used as inputs to the PCPPS metric calculation. Which interactions are missing? Should the addition of any TLV or sub-TLV change the flooding mechanism? [WAJ] In the base document, it mentioned there may be centralized, or distributed. If PCPPS is centralized, as I mentioned above, there is no necessary for the IGP to participate in If PCPPS is distributed, the procedure for consuming such newly defined TLVs should be described. Ron Best Regards Aijun Wang China Telecom -----Original Message----- From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Christian Hopps via Datatracker Sent: Monday, August 17, 2026 8:57 AM To: [email protected]<mailto:[email protected]> Cc: [email protected]<mailto:[email protected]>; [email protected]<mailto:[email protected]>; [email protected]<mailto:[email protected]> Subject: [Lsr] WG adoption call for draft-many-lsr-power-group-03 (Ends 2026-08-30) Hi Folks, This begins a 2 week WG Adoption Call for the following draft: https://urldefense.com/v3/__https://datatracker.ietf.org/doc/draft-many-lsr-power-group/__;!!NpxR!iPWTa_HdgTs4cfKq-wRonK1P2gTSQHdnS6G14eA4oW_y_OIb6VUvnFZwy4DJlK0_xuExEoZ2KnHSBwyHIv92BtCB$<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/draft-many-lsr-power-group/__;!!NpxR!iPWTa_HdgTs4cfKq-wRonK1P2gTSQHdnS6G14eA4oW_y_OIb6VUvnFZwy4DJlK0_xuExEoZ2KnHSBwyHIv92BtCB$> Please indicate your support or objections by August 30th, 2026. An IPR declaration has been made https://urldefense.com/v3/__https://datatracker.ietf.org/ipr/search/?submit=draft&id=draft-many-lsr-power-group__;!!NpxR!iPWTa_HdgTs4cfKq-wRonK1P2gTSQHdnS6G14eA4oW_y_OIb6VUvnFZwy4DJlK0_xuExEoZ2KnHSBwyHIpbPHXJm$<https://urldefense.com/v3/__https:/datatracker.ietf.org/ipr/search/?submit=draft&id=draft-many-lsr-power-group__;!!NpxR!iPWTa_HdgTs4cfKq-wRonK1P2gTSQHdnS6G14eA4oW_y_OIb6VUvnFZwy4DJlK0_xuExEoZ2KnHSBwyHIpbPHXJm$> Authors, please respond to the list indicating whether you are aware of any other IPR that applies to this draft. Thanks, Chris. [Call for adoption end date (2026-08-30)] _______________________________________________ Lsr mailing list -- [email protected]<mailto:[email protected]> To unsubscribe send an email to [email protected]<mailto:[email protected]> _______________________________________________ Lsr mailing list -- [email protected]<mailto:[email protected]> To unsubscribe send an email to [email protected]<mailto:[email protected]> _______________________________________________ Teas mailing list -- [email protected]<mailto:[email protected]> To unsubscribe send an email to [email protected]<mailto:[email protected]> _______________________________________________ Green mailing list -- [email protected]<mailto:[email protected]> To unsubscribe send an email to [email protected]<mailto:[email protected]>
_______________________________________________ Lsr mailing list -- [email protected] To unsubscribe send an email to [email protected]
