Re: [Lsr] draft-ietf-lsr-flex-algo
Gyan Mishra <hayabusagsm@gmail.com> Tue, 19 May 2020 01:52 UTC
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From: Gyan Mishra <hayabusagsm@gmail.com>
Date: Mon, 18 May 2020 21:52:02 -0400
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To: "Wang, Weibin (NSB - CN/Shanghai)" <weibin.wang@nokia-sbell.com>
Cc: Jeff Tantsura <jefftant.ietf@gmail.com>, "Ketan Talaulikar (ketant)" <ketant@cisco.com>, "lsr@ietf.org" <lsr@ietf.org>
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Subject: Re: [Lsr] draft-ietf-lsr-flex-algo
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Flex algo is usually mentioned in the context of SR-TE to help reduced SRH size to circumvent MSD issues for both SRV6 and SR-MPLS, however can the 0-127 flex algo extensions since it’s an IGP extension used in any pure IP network independent of SR flavors SR-MPLS or SRv6. Also can flex algo be used in conjunction with RSVP-TE or PPR(preferred path routing). Kind regards Gyan On Sat, May 9, 2020 at 9:25 PM Wang, Weibin (NSB - CN/Shanghai) < weibin.wang@nokia-sbell.com> wrote: > Jeff, I see what you said, thank you for sharing information; > > > > > > > > Cheers! > > > > Wang Weibin > > > > *From:* Jeff Tantsura <jefftant.ietf@gmail.com> > *Sent:* 2020年5月10日 3:24 > *To:* Wang, Weibin (NSB - CN/Shanghai) <weibin.wang@nokia-sbell.com> > *Cc:* Ketan Talaulikar (ketant) <ketant@cisco.com>; lsr@ietf.org > *Subject:* Re: [Lsr] draft-ietf-lsr-flex-algo > > > > Weibin, > > > > One could have an algo with MSD/ERLD as optimizations constrains, would be > quite similar to colored links. Note - ERLD has implemented node > capabilities only, so all links on a node will have to be pruned. > > The tradeoffs are - having centralized controller with global view > computing a path that meets the constraints(classical BGP-LS + PCEP > scenario) vs building a dynamic topology of connected nodes that meet a set > of constrains, in first case, change in topology/capabilities would cause > path recalculation/reoptimization on the PCE while in the second - IGP > would recompute the topology locally. > > > > Regards, > > Jeff > > > > On May 9, 2020, at 01:27, Wang, Weibin (NSB - CN/Shanghai) < > weibin.wang@nokia-sbell.com> wrote: > > > > Ketan, thank you for clarification. > > > > > > > > Cheers! > > > > Wang Weibin > > > > *From:* Ketan Talaulikar (ketant) <ketant@cisco.com> > *Sent:* 2020年5月9日 14:52 > *To:* Wang, Weibin (NSB - CN/Shanghai) <weibin.wang@nokia-sbell.com>; > lsr@ietf.org > *Subject:* RE: draft-ietf-lsr-flex-algo > > > > Hi Wang, > > > > You are correct. Though I wouldn’t call it a goal but rather a > benefit/advantage – same applies to SR-MPLS where the label stack can be > reduced. > > > > Thanks, > > Ketan > > > > *From:* Lsr <lsr-bounces@ietf.org> *On Behalf Of *Wang, Weibin (NSB - > CN/Shanghai) > *Sent:* 08 May 2020 19:07 > *To:* lsr@ietf.org > *Subject:* [Lsr] draft-ietf-lsr-flex-algo > > > > Hi authors: > > > > After reading through this draft lsr-flex-algo, I want to know whether > there is a potential goal of this draft to reduce the SRH size with > enabling flex-algo with admin group in SRv6 deployment, because without > flex-algo we have to have a big SRH size when the SRH include more SRv6 > SIDs, if we enable flex-algo under special topology and link constraint > condition, in theory we can even construct a end to end SR path/tunnel > without SRH, but it still meet TE requirement. So my question is whether > the flex-algo can be used as tool to reduce SRH size? > > > > > > > > *Cheers !* > > > > *WANG Weibin* > > _______________________________________________ > Lsr mailing list > Lsr@ietf.org > https://www.ietf.org/mailman/listinfo/lsr > > _______________________________________________ > Lsr mailing list > Lsr@ietf.org > https://www.ietf.org/mailman/listinfo/lsr > -- Gyan Mishra Network Engineering & Technology Verizon Silver Spring, MD 20904 Phone: 301 502-1347 Email: gyan.s.mishra@verizon.com
- [Lsr] draft-ietf-lsr-flex-algo Wang, Weibin (NSB - CN/Shanghai)
- Re: [Lsr] draft-ietf-lsr-flex-algo Ketan Talaulikar (ketant)
- Re: [Lsr] draft-ietf-lsr-flex-algo Wang, Weibin (NSB - CN/Shanghai)
- Re: [Lsr] draft-ietf-lsr-flex-algo Jeff Tantsura
- Re: [Lsr] draft-ietf-lsr-flex-algo Wang, Weibin (NSB - CN/Shanghai)
- Re: [Lsr] draft-ietf-lsr-flex-algo Gyan Mishra
- Re: [Lsr] draft-ietf-lsr-flex-algo Peter Psenak
- Re: [Lsr] draft-ietf-lsr-flex-algo Gyan Mishra
- Re: [Lsr] draft-ietf-lsr-flex-algo Peter Psenak
- Re: [Lsr] draft-ietf-lsr-flex-algo Gyan Mishra