Re: [Lsr] LSR WG Adoption Call for "Algorithm Related IGP-Adjacency SID Advertisement"

Hi PSF,

Thanks for your pointer to another document which defines the encodings of per-Algo TE link attributes.

But my comments are related to the text in section 3 and 5 of this document, which describes new use cases and operation of Flex-Algo with per Flex-Algo resource reservation or per Flex-Algo QoS policy on the same link. These require extensions to the function of Flex-Algo, which IMO needs to be discussed and compared with other alternative mechanisms. And as you indicated, there are related encoding extensions proposed in other document, thus it may not be just a local behavior. 

So could you reply to the comments in my previous mail?

Best regards,
Jie

> -----Original Message-----
> From: peng.shaofu@zte.com.cn [mailto:peng.shaofu@zte.com.cn]
> Sent: Friday, May 28, 2021 12:00 PM
> To: Dongjie (Jimmy) <jie.dong@huawei.com>
> Cc: chopps@chopps.org; lsr@ietf.org
> Subject: Re:[Lsr] LSR WG Adoption Call for "Algorithm Related IGP-Adjacency
> SID Advertisement"
> 
> Hi Jie,
> 
> Thanks for your comments.
> 
> In this document, there are not any extensions to describe resource reservation
> per algo. Are you aiming at another draft
> (https://datatracker.ietf.org/doc/draft-cp-lsr-fa-aware-te/) ?  Please find out
> what you are talking about first.
> Adj-SID per algo can distinguish traffic behavior in local. You are welcome to
> add more usecases based on section 3.
> 
> Regards,
> PSF
> 
> 
> ------------------原始邮件------------------
> 发件人：Dongjie(Jimmy)
> 收件人：Christian Hopps;lsr@ietf.org;
> 日 期 ：2021年05月28日 11:40
> 主 题 ：Re: [Lsr] LSR WG Adoption Call for "Algorithm Related IGP-Adjacency
> SID Advertisement"
> Hi,
> I don't support the adoption of this document.
> It seems this document aims to introduce per Flex-Algo Adj-SID to SR-MPLS, its
> typical use case is to provide protection path with Flex-Algo constraints for
> Adj-SID of a particular Flex-Algo, which is described in the case 3 of section 3.
> However, section 3 and section 5 shows that it also aims to introduce further
> changes to the usage and operation of Flex-Algo, which is to provide resource
> reservation based on Flex-Algo. IMO these changes to Flex-Algo deserves
> further discussion and is not only related to the per Flex-Algo Adj-SID extension.
> Here are some comments about this change to Flex-Algo:
> 1. Flex-Algo defines the constraints for path computation in a distributed
> manner, it is not for resource reservation.
> 2. Reserving resources for each Flex-Algo on a link does not make sense. The
> correlation between Flex-Algo and the network links is based on administrative
> groups (color), and the color of the link may or may not be included in the
> Flex-Algo definition. To follow the color based link correlation, a more practical
> approach would be to use Flex-Algo with L2 bundle as defined in
> draft-zhu-lsr-isis-sr-vtn-flexalgo, which uses color to correlate the L3 link and
> the L2 member link to a Flex-Algo, this avoids the extension for per-FlexAlgo
> resource reservation.
> 3. The Flex-Algo link TE attributes are advertised using ASLA, the TE attributes
> are shared by all Flex-Algos which include the link according to the FAD, and
> based on previous discussion, it seems there is no intention to introduce per
> Flex-Algo ID link attributes.
> Best regards,
> Jie
> > -----Original Message-----
> > From: Lsr [mailto:lsr-bounces@ietf.org] On Behalf Of Christian Hopps
> > Sent: Thursday, May 27, 2021 4:57 AM
> > To: lsr@ietf.org
> > Cc: chopps@chopps.org
> > Subject: [Lsr] LSR WG Adoption Call for "Algorithm Related
> > IGP-Adjacency SID Advertisement"
> >
> >
> > Hi Folks,
> >
> > This begins a 2 week WG Adoption Call for the following draft:
> >
> > https://datatracker.ietf.org/doc/draft-peng-lsr-algorithm-related-adja
> > cency-sid
> > /
> >
> > Please indicate your support or objections by June 9th, 2021
> >
> > Authors, please respond to the list indicating whether you are aware
> > of any IPR that applies to this draft.
> >
> > Thanks,
> > Acee and Chris.
> >
> > _______________________________________________
> > Lsr mailing list
> > Lsr@ietf.org
> > https://www.ietf.org/mailman/listinfo/lsr
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