Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-ospf-segment-routing-extensions
Pushpasis Sarkar <psarkar@juniper.net> Mon, 05 January 2015 06:16 UTC
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From: Pushpasis Sarkar <psarkar@juniper.net>
To: Pushpasis Sarkar <psarkar@juniper.net>, "Les Ginsberg (ginsberg)" <ginsberg@cisco.com>, Shraddha Hegde <shraddha@juniper.net>, "Peter Psenak (ppsenak)" <ppsenak@cisco.com>, "draft-ietf-ospf-segment-routing-extensions@tools.ietf.org" <draft-ietf-ospf-segment-routing-extensions@tools.ietf.org>, "draft-ietf-isis-segment-routing-extensions@tools.ietf.org" <draft-ietf-isis-segment-routing-extensions@tools.ietf.org>, Hannes Gredler <hannes@juniper.net>
Thread-Topic: [OSPF] [Isis-wg] Mail regarding draft-ietf-ospf-segment-routing-extensions
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Date: Mon, 05 Jan 2015 06:16:35 +0000
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Subject: Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-ospf-segment-routing-extensions
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Some typo correction inline.. On 1/5/15, 11:43 AM, "Pushpasis Sarkar" <psarkar@juniper.net> wrote: >Hi Les, > > >On 1/5/15, 11:23 AM, "Les Ginsberg (ginsberg)" <ginsberg@cisco.com> wrote: > >>Pushpasis - >> >>The key point is that the proposal does not have any lasting impact on >>traffic flow. A simple topology should suffice to illustrate this. >> >> >>A----B----C----D >> | | >> E----F >> >>(All links have the same cost) >> >>Suppose we wish to have traffic entering at A flow along the path A-B-C-D >>- but if the link B---C fails we do NOT want traffic to take the path >>B--E--F--C. >> >>You propose to have C advertise an address with two node-sids - one which >>allows protection - call it C(P) - and one which does NOT allow >>protection - call it C(NP). >[Pushpasis] No. My proposal is for D to advertise two node sids, D1 with >NP set to 0 and D2 with NP set to 1. Applications on route A that do not >need B, >or C to protect the A-B-C-D path will use D2. B and C will not install >backup paths for D2. Other apps can use D1 as they are supposed to do >otherwise. Wether to protect D1 or not is a local decision of B and C. >Hope I could clarify enough :) > >> >>If the label stack specifies C(NP) - then while the link B--C is UP >>everything works as desired (primary path to C(NP) on Node B is via link >>B-C). >>However, when the link B--C goes down, the network will reconverge and in >>a modest amount of time the new primary path to C(NP) on node B will be >>via link B-E. >[Pushpasis] Yes agreed. But only applications on A will be injecting >traffic using D2. Once the B-C link-down event reaches router A will stop >injecting traffic using D2. A path re-compute will be triggered on A. Yes >I agree that if B converges D2 (not FRR) before A re-compute, there is >still chance that some small amount of traffic is sent over A-B-E-F-C-D. > >> >>The existence of C(NP) therefore only affects traffic flow during the >>reconvergence period i.e. if we assume B did NOT install a repair path >>for C(NP) traffic will be dropped only until a new primary path is >>calculated. I don’t see the value in this. >> >>As a (somewhat dangerous) aside, the functionality you are looking for is >>more akin to "not-via" as defined in RFC 6981 - though I am quick to add >>that I am NOT proposing to pursue that. :-) >>But reading that RFC might give you more insight into why simply setting >>"don't protect" for a prefix isn't useful for the purpose you have in >>mind. >> >> Les >> >> >> >>-----Original Message----- >>From: Pushpasis Sarkar [mailto:psarkar@juniper.net] >>Sent: Sunday, January 04, 2015 8:34 PM >>To: Les Ginsberg (ginsberg); Shraddha Hegde; Peter Psenak (ppsenak); >>draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>draft-ietf-isis-segment-routing-extensions@tools.ietf.org; Hannes Gredler >>Cc: ospf@ietf.org; isis-wg@ietf.org >>Subject: Re: [OSPF] [Isis-wg] Mail regarding >>draft-ietf-ospf-segment-routing-extensions >> >>Hi Les, >> >>Please find comments inline.. >> >>Authors, >> >>Here is my proposal. Please let me know if this sounds reasonable or not. >> >>- A new ŒNo-Potection-Required¹ or ŒNP¹ flag be added to the Prefix-SID >>Sub-TLV/TLV. Setting this flag means none of the transit routers should >>try to protect this node-segment. >>- Let nodes advertise two node-sid-index each (per address-family), one >>without and one with ŒNP¹ flag set. For node-sid advertised with ŒNP¹ >>flag 0, routers same behave the same way as today. But when they receive >>a node-sid with ŒNP¹ flag set, they avoid/skip finding a backup for that >>segment. >>- Finally ingress servers or TE-applications may use these 'node-sids >>with NP-flag set¹ for use cases where it is better to drop traffic on >>topology outages rather than diverting it to some other paths. For such >>cases ingress router or TE-applications should look for node-sids with >>ŒNP¹ flag set and not the regular node-sids. For all other normal use >>cases(including L3VPN/6VPE etc) traffic should be carried using node-sid >>without ŒNP‹flag set. >> >>Thanks and Regards, >>-Pushpasis >> >>On 1/5/15, 3:37 AM, "Les Ginsberg (ginsberg)" <ginsberg@cisco.com> wrote: >> >>>Pushpasis - >>> >>>I don't agree. >>> >>>The use of one node-sid vs another has nothing whatever to do with the >>>request Shraddha has made i.e. should we introduce a flag indicating >>>whether a particular prefix should be protected or not. A node-sid only >>>dictates what (intermediate) node traffic should be sent to - not what >>>link(s) are used to reach that node. >>[Pushpasis] This is not about which links to take. It is about wether >>transit routers should try to protect the node-segment to the this >>node-sid or not. I think this opens up a lot many number of possibilities >>on the ingress router and TE controller-based applications. >> >>> >>>Adjacency-sids have a different semantic - they identify the link over >>>which traffic is to be forwarded. Identifying an adjacency-sid as >>>unprotected means traffic will NEVER flow over a different link. There >>>is no equivalent behavior w a node-sid - which is what this discussion >>>has been about. >>[Pushpasis] I am not trying to draw a parallel between this new flag and >>the ŒB¹ flag in Adj-Sid SubTlv. Like said before >> >>> >>> Les >>> >>> >>>-----Original Message----- >>>From: Pushpasis Sarkar [mailto:psarkar@juniper.net] >>>Sent: Sunday, January 04, 2015 8:51 AM >>>To: Les Ginsberg (ginsberg); Shraddha Hegde; Peter Psenak (ppsenak); >>>draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>Cc: ospf@ietf.org; isis-wg@ietf.org >>>Subject: Re: [OSPF] [Isis-wg] Mail regarding >>>draft-ietf-ospf-segment-routing-extensions >>> >>>Hi Les, >>> >>>I think the requirement Shraddha is referring is about the choice of >>>exact node-sid to use while constructing the label-stack for a >>>explicit-LSP on the ingress router, which will be typically done after >>>running some CSPF on the SPRING topology. And not the IGP on ingress or >>>transit routers. >>> >>>Thanks >>>-Pushpasis >>> >>>On 1/3/15, 3:10 AM, "Les Ginsberg (ginsberg)" <ginsberg@cisco.com> >>>wrote: >>> >>>>Shraddha - >>>> >>>>IGPs today do NOT perform constraint based SPFs - so I don't know why >>>>you believe that the primary SPF will meet a set of constraints that >>>>an LFA calculation will not. In fact , it is the opposite which is >>>>true because implementations today do support preferences in choosing >>>>LFAs based on various configured policy - something which is NOT done >>>>for primary SPF. >>>> >>>>If you want a certain class of traffic to avoid a subset of the links >>>>in the topology then you need to have a way of identifying the links >>>>(NOT the node addresses) and a way of calculating a path which only >>>>uses the links which meet the constraints of that class of service. >>>>Identifying a particular prefix as protected or unprotected won't >>>>achieve that. >>>> >>>> Les >>>> >>>>-----Original Message----- >>>>From: Shraddha Hegde [mailto:shraddha@juniper.net] >>>>Sent: Friday, January 02, 2015 10:54 AM >>>>To: Les Ginsberg (ginsberg); Peter Psenak (ppsenak); >>>>draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>Cc: ospf@ietf.org; isis-wg@ietf.org >>>>Subject: RE: [Isis-wg] Mail regarding >>>>draft-ietf-ospf-segment-routing-extensions >>>> >>>>Hi Les/Peter, >>>> >>>> When reconvergence happens, the primary path will be calculated >>>>based on all constriants. >>>>This is not true with the protection path.Protection path is >>>>calculated locally (LFA/RLFA) and does not consider the >>>>characteristics of the services running on that path. >>>>It's easier for some services to pick the unprotected path when the >>>>nature of the service is that it can be restarted when there is a >>>>disconnection. >>>> >>>>Rgds >>>>Shraddha >>>>-----Original Message----- >>>>From: Les Ginsberg (ginsberg) [mailto:ginsberg@cisco.com] >>>>Sent: Friday, January 02, 2015 10:06 PM >>>>To: Peter Psenak (ppsenak); Shraddha Hegde; >>>>draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>Cc: ospf@ietf.org; isis-wg@ietf.org >>>>Subject: RE: [Isis-wg] Mail regarding >>>>draft-ietf-ospf-segment-routing-extensions >>>> >>>>Peter - >>>> >>>>The requirement Shraddha specified was to not allow a particular class >>>>of service ("heavy bandwidth services" was the example provided) to >>>>use certain links in the topology. My point is that advertising a flag >>>>for a given prefix which says "do not calculate a repair path for this >>>>prefix" >>>>does not help achieve this. Once the network reconverges following the >>>>failure of one of the links on which "heavy bandwidth services" is >>>>allowed/preferred it is quite likely that the new best path will be >>>>over a link on which "heavy bandwidth services" is NOT >>>>allowed/preferred. This will happen whether you have the new flag or >>>>not - so the flag will have no lasting effect. It would only affect >>>>traffic flow during the brief period during which the network is >>>>reconverging. >>>> >>>>I think you and I are actually in agreement - I am simply sending a >>>>stronger negative message - not only do I think the flag is not useful >>>>- I think it does not achieve the goal Shraddha has in mind. >>>> >>>> Les >>>> >>>> >>>>-----Original Message----- >>>>From: Peter Psenak (ppsenak) >>>>Sent: Friday, January 02, 2015 12:18 AM >>>>To: Les Ginsberg (ginsberg); Shraddha Hegde; >>>>draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>Cc: ospf@ietf.org; isis-wg@ietf.org >>>>Subject: Re: [Isis-wg] Mail regarding >>>>draft-ietf-ospf-segment-routing-extensions >>>> >>>>Hi Les, >>>> >>>>I believe the idea is not to exclude any particular link, it's >>>>actually much simpler - do not calculate backup for the prefix if the >>>>flag is set. >>>> >>>>I'm still not quite sure how useful above is, but technically it is >>>>possible. >>>> >>>>thanks, >>>>Peter >>>> >>>>On 12/30/14 17:22 , Les Ginsberg (ginsberg) wrote: >>>>> Shraddha - >>>>> >>>>> When performing a best path calculation whether a given link is in >>>>>the set of best paths (to be protectedED) or not (could be used as a >>>>>protectING path) is a function of the topology - not the link. If >>>>>there is a topology change it is quite likely that a given link will >>>>>change from being a protectED link to being a protectING link (or >>>>>vice versa). >>>>>So what you propose regarding node-SIDs would not work. >>>>> >>>>> In the use case you mention below if you don't want a certain class >>>>>of traffic to flow on a given link it requires a link attribute which >>>>>is persistent across topology changes. There are ways to do that - >>>>>using Adj-SIDs is one of them. But using node-SIDs in the way you >>>>>propose is NOT. >>>>> >>>>> Les >>>>> >>>>> -----Original Message----- >>>>> From: OSPF [mailto:ospf-bounces@ietf.org] On Behalf Of Shraddha >>>>> Hegde >>>>> Sent: Monday, December 29, 2014 10:12 PM >>>>> To: Peter Psenak (ppsenak); >>>>> draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>> draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>> Cc: ospf@ietf.org; isis-wg@ietf.org >>>>> Subject: Re: [OSPF] [Isis-wg] Mail regarding >>>>> draft-ietf-ospf-segment-routing-extensions >>>>> >>>>> Peter, >>>>> >>>>>> The requirement here is to get an un-protected path for services >>>>>>which do not want to divert the traffic on protected path in any >>>>>>case. >>>>> >>>>>> can you give an example of such a service and a reasoning why such >>>>>>service would want to avoid local protection along the path? >>>>> >>>>> Heavy bandwidth services are potential candidates. The network is >>>>>well planned and well provisioned for primary path but same is not >>>>>true for backup paths. >>>>> Diverting heavy bandwidth services along protection path can disrupt >>>>>the other services on that path, they are better-off un-protected so >>>>>that an event in the network Would result in disconnection and a >>>>>retry for such services. >>>>> >>>>> Rgds >>>>> Shraddha >>>>> >>>>> -----Original Message----- >>>>> From: Peter Psenak [mailto:ppsenak@cisco.com] >>>>> Sent: Monday, December 29, 2014 4:35 PM >>>>> To: Shraddha Hegde; >>>>> draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>> draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>> Cc: ospf@ietf.org; isis-wg@ietf.org >>>>> Subject: Re: [Isis-wg] Mail regarding >>>>> draft-ietf-ospf-segment-routing-extensions >>>>> >>>>> Shraddha, >>>>> >>>>> On 12/29/14 10:06 , Shraddha Hegde wrote: >>>>>> Peter, >>>>>> >>>>>> The requirement here is to get an un-protected path for services >>>>>>which do not want to divert the traffic on protected path in any >>>>>>case. >>>>> >>>>> can you give an example of such a service and a reasoning why such >>>>>service would want to avoid local protection along the path? >>>>> >>>>> thanks, >>>>> Peter >>>>> >>>>>> So when the originator of node-sid signals un-protected path >>>>>>requirement, there is always an unprotected path. >>>>>> >>>>>> Regarding the protected path, it is the default behavior as it >>>>>>exists today. You get protection if it's available otherwise you >>>>>>don't get protection. >>>>>> >>>>>> In fact, you can have the new flag to say "NP flag" meaning >>>>>>non-protected flag which can be set for the unprotected path. >>>>>> By default it remains off and gives the behavior as it exists today. >>>>>> >>>>>> >>>>>> Rgds >>>>>> Shraddha >>>>>> >>>>>> -----Original Message----- >>>>>> From: Peter Psenak [mailto:ppsenak@cisco.com] >>>>>> Sent: Monday, December 29, 2014 2:26 PM >>>>>> To: Shraddha Hegde; >>>>>> draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>>> draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>>> Cc: ospf@ietf.org; isis-wg@ietf.org >>>>>> Subject: Re: [Isis-wg] Mail regarding >>>>>> draft-ietf-ospf-segment-routing-extensions >>>>>> >>>>>> Shraddha, >>>>>> >>>>>> I do not see how an originator of the node-sid can mandate a >>>>>>protection for the prefix on other routers. What if there is no >>>>>>backup available on a certain node along the path? >>>>>> >>>>>> The parallel with the B-flag in adj-sids is not right - in case of >>>>>>adj-sid the originator has the knowledge about the local adjacency >>>>>>protection and as such can signal it it it's LSA. >>>>>> >>>>>> thanks, >>>>>> Peter >>>>>> >>>>>> >>>>>> On 12/29/14 09:47 , Shraddha Hegde wrote: >>>>>>> Peter, >>>>>>> >>>>>>> >>>>>>> Pls see inline. >>>>>>> >>>>>>> Rgds >>>>>>> Shraddha >>>>>>> >>>>>>> -----Original Message----- >>>>>>> From: Peter Psenak [mailto:ppsenak@cisco.com] >>>>>>> Sent: Monday, December 29, 2014 2:02 PM >>>>>>> To: Shraddha Hegde; >>>>>>> draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>>>> draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>>>> Cc: ospf@ietf.org; isis-wg@ietf.org >>>>>>> Subject: Re: [Isis-wg] Mail regarding >>>>>>> draft-ietf-ospf-segment-routing-extensions >>>>>>> >>>>>>> Shraddha, >>>>>>> >>>>>>> I do not see how an originator can set any flag regarding the >>>>>>>protection of the locally attached prefix. >>>>>>> <Shraddha> The originator advertises 2 node-sids. One with p flag >>>>>>>set and the other without the p-flag set. >>>>>>> >>>>>>> It's all the routers on the path towards such prefix that need >>>>>>>to deal with the protection. >>>>>>> <Shraddha> The receiving nodes will download protected path for >>>>>>>the node-sid with p-flag set and download Unprotected path for the >>>>>>>node-sid with p-flag unset. >>>>>>> >>>>>>> Signaling anything from the originator seems useless. >>>>>>> <Shraddha> For node-sids it's the others who need to build the >>>>>>>forwarding plane but it's only the originator who can signal which >>>>>>>of >>>>>>> Sid need to be built with protection >>>>>>>and which not. Other routers on the path cannot signal this >>>>>>>information. >>>>>> >>>>>> >>>>>> >>>>>>> >>>>>>> With this you have two paths for the node. One is protected and >>>>>>>the other is unprotected. This meets the requirement of having an >>>>>>>un-protected path. >>>>>>> >>>>>>> It's very much in parallel to B-flag in adj-sids. It is similar to >>>>>>>advertising multiple adj-sids one with B-flag on and other with >>>>>>>b-flag off , to get protected and unprotected Adj-sids. >>>>>>> >>>>>>> thanks, >>>>>>> Peter >>>>>>> >>>>>>> On 12/29/14 09:26 , Shraddha Hegde wrote: >>>>>>>> Yes.You are right. >>>>>>>> >>>>>>>> Lets say a prefix sid has a flag "p flag". If this is on it means >>>>>>>>build a path and provide protection. >>>>>>>> If this is off it means build a path with no protection. >>>>>>>> The receivers of the prefix-sid will build forwarding plane based >>>>>>>>on this flag. >>>>>>>> >>>>>>>> The applications building the paths will either use prefix-sids >>>>>>>>with p flag on or off based on the need of the service. >>>>>>>> Rgds >>>>>>>> Shraddha >>>>>>>> >>>>>>>> >>>>>>>> -----Original Message----- >>>>>>>> From: Peter Psenak [mailto:ppsenak@cisco.com] >>>>>>>> Sent: Monday, December 29, 2014 1:49 PM >>>>>>>> To: Shraddha Hegde; >>>>>>>> draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>>>>> draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>>>>> Cc: ospf@ietf.org; isis-wg@ietf.org >>>>>>>> Subject: Re: [Isis-wg] Mail regarding >>>>>>>> draft-ietf-ospf-segment-routing-extensions >>>>>>>> >>>>>>>> Shraddha, >>>>>>>> >>>>>>>> the problem is that the node that is advertising the node-sid can >>>>>>>>not advertise any data regarding the protection of such prefix, >>>>>>>>because the prefix is locally attached. >>>>>>>> >>>>>>>> thanks, >>>>>>>> Peter >>>>>>>> >>>>>>>> On 12/29/14 09:15 , Shraddha Hegde wrote: >>>>>>>>> Peter, >>>>>>>>> >>>>>>>>> If there is a service which has to use un-protected path and >>>>>>>>>while building such a path if the node-sids Need to be used (one >>>>>>>>>reason could be label stack compression) , then there has to be >>>>>>>>>unprotected node-sid that this service can make use of. >>>>>>>>> >>>>>>>>> Prefix -sids could also be used to represent different service >>>>>>>>>endpoints which makes it even more relevant to have A means of >>>>>>>>>representing unprotected paths. >>>>>>>>> >>>>>>>>> Would be good to hear from others on this, especially operators. >>>>>>>>> >>>>>>>>> Rgds >>>>>>>>> Shraddha >>>>>>>>> >>>>>>>>> >>>>>>>>> -----Original Message----- >>>>>>>>> From: Peter Psenak [mailto:ppsenak@cisco.com] >>>>>>>>> Sent: Monday, December 29, 2014 1:35 PM >>>>>>>>> To: Shraddha Hegde; >>>>>>>>> draft-ietf-ospf-segment-routing-extensions@tools.ietf.org; >>>>>>>>> draft-ietf-isis-segment-routing-extensions@tools.ietf.org >>>>>>>>> Cc: ospf@ietf.org; isis-wg@ietf.org >>>>>>>>> Subject: Re: [Isis-wg] Mail regarding >>>>>>>>> draft-ietf-ospf-segment-routing-extensions >>>>>>>>> >>>>>>>>> Shraddha, >>>>>>>>> >>>>>>>>> node-SID is advertised by the router for the prefix that is >>>>>>>>>directly attached to it. Protection for such local prefix does >>>>>>>>>not mean much. >>>>>>>>> >>>>>>>>> thanks, >>>>>>>>> Peter >>>>>>>>> >>>>>>>>> On 12/24/14 11:57 , Shraddha Hegde wrote: >>>>>>>>>> Authors, >>>>>>>>>> We have a "backup flag" in adjacency sid to indicate whether >>>>>>>>>> the label is protected or not. >>>>>>>>>> Similarly. I think we need a flag in prefix-sid as well to >>>>>>>>>> indicate whether the node-sid is to be protected or not. >>>>>>>>>> Any thoughts on this? >>>>>>>>>> Rgds >>>>>>>>>> Shraddha >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Isis-wg mailing list >>>>>>>>>> Isis-wg@ietf.org >>>>>>>>>> https://www.ietf.org/mailman/listinfo/isis-wg >>>>>>>>>> >>>>>>>>> >>>>>>>>> . >>>>>>>>> >>>>>>>> >>>>>>>> . >>>>>>>> >>>>>>> >>>>>>> . >>>>>>> >>>>>> >>>>>> . >>>>>> >>>>> >>>>> _______________________________________________ >>>>> OSPF mailing list >>>>> OSPF@ietf.org >>>>> https://www.ietf.org/mailman/listinfo/ospf >>>>> . >>>>> >>>> >>>>_______________________________________________ >>>>OSPF mailing list >>>>OSPF@ietf.org >>>>https://www.ietf.org/mailman/listinfo/ospf >>> >> > >_______________________________________________ >OSPF mailing list >OSPF@ietf.org >https://www.ietf.org/mailman/listinfo/ospf
- [OSPF] Mail regarding draft-ietf-ospf-segment-rou… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Peter Psenak
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Peter Psenak
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Peter Psenak
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Peter Psenak
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Rob Shakir
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Rob Shakir
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Rob Shakir
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Peter Psenak
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Les Ginsberg (ginsberg)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Peter Psenak
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Les Ginsberg (ginsberg)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Les Ginsberg (ginsberg)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Peter Psenak
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Pushpasis Sarkar
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Les Ginsberg (ginsberg)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Jeff Tantsura
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Pushpasis Sarkar
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Les Ginsberg (ginsberg)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Les Ginsberg (ginsberg)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Pushpasis Sarkar
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Pushpasis Sarkar
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Les Ginsberg (ginsberg)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Mitchell Erblich
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Shraddha Hegde
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Les Ginsberg (ginsberg)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Rob Shakir
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… stephane.litkowski
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… stephane.litkowski
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… stephane.litkowski
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… bruno.decraene
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… stephane.litkowski
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… bruno.decraene
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Henderickx, Wim (Wim)
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… stephane.litkowski
- Re: [OSPF] [Isis-wg] Mail regarding draft-ietf-os… Henderickx, Wim (Wim)