Re: [Isis-wg] WG Last Call for draft-ietf-isis-reverse-metric-07
Christian Hopps <chopps@chopps.org> Wed, 24 January 2018 11:32 UTC
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From: Christian Hopps <chopps@chopps.org>
To: "Naiming Shen (naiming)" <naiming@cisco.com>
Cc: Les Ginsberg <ginsberg@cisco.com>, "isis-wg@ietf.org" <isis-wg@ietf.org>, "isis-ads@ietf.org" <isis-ads@ietf.org>
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Date: Wed, 24 Jan 2018 06:32:28 -0500
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Subject: Re: [Isis-wg] WG Last Call for draft-ietf-isis-reverse-metric-07
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Here are my comments on -08. The most important one would be the M-ISIS discrepancy. - 3.1 " If an IS-IS router is configured to originate a TE Default Metric sub-TLV for a link, but receives a Reverse Metric TLV from its neighbor that does not contain a TE Default Metric sub-TLV, then the IS-IS router MUST NOT change the value of its TE Default Metric sub- TLV for that link." - so this is a reversal from -07, where it said it MUST add the metric offset value to the TE default metric. Note this is also not updated in M-ISIS section. - 3.1 "Routers MUST scan the Metric Offset value and TE sub-TLVs in all subsequently received Reverse Metric TLVs. If changes are observed by a receiver of the Reverse Metric TLV in the Metric Offset value or TE Default Metric sub-TLV value, the receiving router MUST update its advertised IS-IS default metric or Traffic Engineering parameters in the appropriate TLVs, recompute its SPF tree and flood new LSPs to other IS-IS routers. - I don't like this, why do we have to say, "pay attention to and act on updates to the value?" When do we *not* do this in routing protocols? - If we keep this text, change to "subsequently received IIH" as one might read this meaning that we accept multiple TLVs per IIH which we don't. - 3.2 "The Reverse Metric TLV is applicable to Multi-Topology IS-IS (M-ISIS) [RFC5120] capable point-to-point links. If an IS-IS router is configured for M-ISIS it MUST send only a single Reverse Metric TLV in IIH PDUs toward its neighbor(s) on the designated link that is about to undergo maintenance." - There are other reasons to set the reverse metric (e.g., high BER on receive). - 3.2 "If an M-ISIS router is configured to advertise TE Default Metric sub-TLVs for one or more topologies, but does not receive a TE Default Metric sub-TLV in a Reverse Metric TLV, then the M-ISIS router MUST add the value in Metric Offset field of the Reverse Metric TLV to each of the TE Default Metric sub-TLVs for all topologies. The M-ISIS should flood its newly updated MT IS TLVs and recompute its SPF/CSPF accordingly." - This is opposite the changed behavior described in 3.1. - 3.4 P2P change says "Must Add" and removed the text about not going to overload-max value. (2^24-1), should probably say "must add according to the rules found in 3.1? Thanks, Chris. Naiming Shen (naiming) <naiming@cisco.com> writes: > Hi Chris, > >> On Jan 11, 2018, at 1:19 AM, Christian Hopps >> <chopps@chopps.org> wrote: >> >> >> Naiming Shen (naiming) <naiming@cisco.com> writes: >> >>> Hi, >>> >>> Sounds reasonable. At this stage of the draft, we’ll probably >>> skip this >>> capability. If it is found needed later, it can be added >>> easily. I suspect >>> there are a number of other things can be later ride on top of >>> this. >> >> Hi Naiming, >> >> Correct me if I'm wrong, but aren't you saying here that you >> would not >> add the 2^24-1 functionality? I'm asking b/c you also just >> published a >> new version -08 that appears to add this functionality. :) >> >> Was there any off-list discussion that led to the change of >> heart? > > Actually, this is not really a new functionality of the draft:-) > We also removed the section 3.6 “Link Overload Attribute Bit” of > sub-TLV of TLV 22 in the LSP. This change is due to several > factors: > > - the long discusion ongoing of OSPF mailing list of the name > “overload”, > which has disagreement on what does this “overload” really > meant, > and what to do if it’s “overloaded”. This version 7 borrowed > this from > OSPF, and now we got requests also to reconsider the name of > this > “Link Overload Attribute Bit” > > - More importantly we just realized that, to use this “overload” > bit in LSP, > the backwards compatibility is not possible anymore, as in the > other > “reverse-metric” feature which is all local to the link. So, if > we have to > use this “overload” bit in LSP, we have also to define the > router > “capabilities” to advertise this, and synchronize among > area/domain, > which we really don’t want to do in ‘reverse-metric' > > - Third with this “U” bit, it achieves the same effect of the > “overload” bit, > since the neighbor can optionally set the (2^24-1) and take out > the > link as ‘unusable’ for IGP or TE, while at the mean time keep > the same > backwards compatibility in the area/domain, which is a very > clean solution. > > - I have had long email/chat discussion on this with Les, since > we have > seen the email, this (2^24-1) has been part of the comments > discussion > during the last call. and at the time I didn’t think clearly and > mentioned on > the list we wouldn't do that, but with all the above mentioned > reasons, > we decided that is the right way to go. As mentioned, the reason > of doing > that is not to handle the multi-area LDP/IGP sync kind of > use-case, but > to support TE topology to take the link out just as in the > removed > section 3.6 in ver 7. > > thanks. > - Naiming > >> >> Thanks, >> Chris. >> >>> Regards, >>> - Naiming >>> >>> On Dec 30, 2017, at 4:05 PM, Les Ginsberg (ginsberg) >>> <ginsberg@cisco.com<mailto:ginsberg@cisco.com>> wrote: >>> >>> >>> >>> From: Alexander Okonnikov >>> [mailto:alexander.okonnikov@gmail.com] >>> Sent: Saturday, December 30, 2017 3:34 PM >>> To: Les Ginsberg (ginsberg) >>> <ginsberg@cisco.com<mailto:ginsberg@cisco.com>> >>> Cc: Naiming Shen (naiming) >>> <naiming@cisco.com<mailto:naiming@cisco.com>>; >>> isis-wg@ietf.org<mailto:isis-wg@ietf.org>; Christian Hopps >>> <chopps@chopps.org<mailto:chopps@chopps.org>>; >>> isis-ads@ietf.org<mailto:isis-ads@ietf.org> >>> Subject: Re: [Isis-wg] WG Last Call for >>> draft-ietf-isis-reverse-metric-07 >>> >>> Les, >>> >>> >>> 31 дек. 2017 г., в 2:25, Les Ginsberg (ginsberg) >>> <ginsberg@cisco.com<mailto:ginsberg@cisco.com>> написал(а): >>> >>> Alex - >>> >>> From: Alexander Okonnikov >>> [mailto:alexander.okonnikov@gmail.com] >>> Sent: Saturday, December 30, 2017 3:06 PM >>> To: Les Ginsberg (ginsberg) >>> <ginsberg@cisco.com<mailto:ginsberg@cisco.com>> >>> Cc: Naiming Shen (naiming) >>> <naiming@cisco.com<mailto:naiming@cisco.com>>; >>> isis-wg@ietf.org<mailto:isis-wg@ietf.org>; Christian Hopps >>> <chopps@chopps.org<mailto:chopps@chopps.org>>; >>> isis-ads@ietf.org<mailto:isis-ads@ietf.org> >>> Subject: Re: [Isis-wg] WG Last Call for >>> draft-ietf-isis-reverse-metric-07 >>> >>> Les, >>> >>> >>> >>> 31 дек. 2017 г., в 1:48, Les Ginsberg (ginsberg) >>> <ginsberg@cisco.com<mailto:ginsberg@cisco.com>> написал(а): >>> >>> Alex - >>> >>> From: Alexander Okonnikov >>> [mailto:alexander.okonnikov@gmail.com] >>> Sent: Saturday, December 30, 2017 2:38 PM >>> To: Les Ginsberg (ginsberg) >>> <ginsberg@cisco.com<mailto:ginsberg@cisco.com>> >>> Cc: Naiming Shen (naiming) >>> <naiming@cisco.com<mailto:naiming@cisco.com>>; >>> isis-wg@ietf.org<mailto:isis-wg@ietf.org>; Christian Hopps >>> <chopps@chopps.org<mailto:chopps@chopps.org>>; >>> isis-ads@ietf.org<mailto:isis-ads@ietf.org> >>> Subject: Re: [Isis-wg] WG Last Call for >>> draft-ietf-isis-reverse-metric-07 >>> >>> Hi Les, >>> >>> Don't advertise link and advertise it with metric 2^24-1 makes >>> sense again. In the former case that link cannot be used for >>> TE LSPs, while in latter one it is possible. This is also >>> described in RFC 5305: >>> >>> " If a link is advertised with the maximum link metric (2^24 >>> - 1), this >>> link MUST NOT be considered during the normal SPF computation. >>> This >>> will allow advertisement of a link for purposes other than >>> building >>> the normal Shortest Path Tree. An example is a link that is >>> available for traffic engineering, but not for hop-by-hop >>> routing." >>> >>> [Les:] I am well aware of this. My comment regarding (2^24 - >>> 1) is in the context of reverse metric. If the reason that you >>> want to advertise (2^24-1) is because the link is only >>> supposed to be used for TE purposes then this would already >>> have been done by the neighbor as part of their configuration >>> – and it has nothing to do with adjacency bringup. >>> Idea was to temporarily disable IP forwarding on the link >>> while preserve ability to use link for other transport. An >>> example when we need it - IGP-LDP sync. If you configure >>> 2^24-1 on the neighbor, then link will be excluded from IP >>> topology permanently. Also, it is not clear for me how it >>> could be done on LAN. >>> >>> >>> [Les:] My point is – if you do not want the link to be used at >>> all – even if only while waiting for LDP sync to complete – >>> then you simply don’t advertise the adjacency. In the case of >>> the LAN you don’t advertise the adjacency to the DIS – so >>> there is no 2-way connectivity on that circuit and no traffic >>> flows to/from the node via the interface in question. It does >>> not matter what the neighbor/DIS is advertising. >>> My point - to have ability to exclude link from IP topology, >>> but still use it in other topologies. This could be done by >>> advertising metric 2^24-1. If adjacency is not advertised, >>> then that link is excluded from all topologies, not only from >>> IP. In general my proposal is to make reverse-metric >>> functionality as flexible as possible and to don't restrict it >>> deliberately. >>> >>> [Les:] This is exactly what I object to. Reverse-metric is not >>> and should not be a general purpose mechanism to have one node >>> override the configuration of its neighbors for any and all >>> possible reasons. It has well defined use cases which the >>> draft describes and its use should be limited to those cases. >>> >>> The additional use cases you have suggested can already be >>> handled by existing mechanisms which are local to each node >>> and that should always be the preferred means. The potential >>> for chaos that results when each node utilizes this mechanism >>> to adjust the SPF outcome on other routers based on its local >>> view of the current state of convergence is not something I >>> want to embrace. >>> >>> Les >>> >>> >>> >>> Regarding L1 circuit between L1/L2 routers - it is not always >>> possible or is not desired. >>> >>> [Les:] I was covering the example you provided. It was clear >>> from your example that although L2 only was enabled between >>> the L1/L2 routers, you were allowing intra-area traffic to >>> flow over that link. >>> If you do not want intra-area traffic to flow over that link >>> at all, then you need to insure that L1 destinations are not >>> leaked into L2 – in which case the proposed change you are >>> suggesting for reverse-metric would not help. >>> >>> If you think you have a different example that justifies your >>> proposal I would be happy to review it – but the one you have >>> come up with isn’t compelling. >>> Two L1/L2 routers could be geographically dispersed. >>> [Les:] Only if the L1/L2 routers are in different areas – in >>> which case your example does not apply. >>> Not necessary. There could be area represented by sub-ring >>> physical topology. >>> >>> >>> There could be L2 subdomain which provides L2 path between >>> them. But sometimes it is not optimal to configure L1/L2 on >>> all transit L2 routers between two ones. Also, for redundancy >>> you will need to provide alternative L1 path in the core (to >>> avoid routing traffic via access). >>> >>> Another case, when having looped L1 is not desired - when R3 >>> has reachability to the network via two ABRs (R1 and R2), and >>> R2 is closer to R3 than R1 to R3. In case link (path) from R3 >>> to R2 is broken, it is more optimal from data path perspective >>> to reroute traffic to R1 rather than to R2 via R1. It is not >>> case for regular IP routing, but becomes sensitive when we >>> have deal with L2VPN services, such that MS-PW or H-VPLS, >>> where R1 and R2 are S-PEs or Hub PEs, respectively. >>> >>> [Les:] We are not discussing all possible network topologies. >>> The topic here is the Reverse-Metric draft and whether there >>> is a use case for a node to tell its neighbor to advertise >>> max-metric (2^24-1). >>> Please stay on topic. If you have an example that justifies >>> your proposal I would like to hear it – but please stay >>> focused on this use case. >>> >>> Les >>> >>> >>> >>> Les >>> >>> Thank you. >>> >>> >>> >>> >>> 31 дек. 2017 г., в 1:33, Les Ginsberg (ginsberg) >>> <ginsberg@cisco.com<mailto:ginsberg@cisco.com>> написал(а): >>> >>> I strongly disagree with this proposed change. >>> >>> If you want to take the link totally out of the topology then >>> simply don’t advertise the adjacency. This works for both P2P >>> and LAN cases. >>> This is why the draft states >>> >>> “a receiver of a >>> Reverse Metric TLV MUST use the numerically smallest value of >>> either >>> the sum of its existing default metric and the Metric Offset >>> value in >>> the Reverse Metric TLV or (2^24 - 2)” >>> >>> There is no use case for (2^24 - 1). >>> >>> As for the L1/L2 example topology that Alex used to justify >>> his proposal, there is a much better way to prevent the >>> premature use of the L1 link. That is to enable L1 on the link >>> between the two L1L2 routers but configure a larger metric >>> (e.g. 100000) so that the L1/L2 link will only be used for L1 >>> traffic when there is no viable L1 only link. There is no need >>> to use Reverse-Metric to do so and I believe this is an >>> inappropriate use of this extension. >>> >>> Les >>> >>> >>> From: Isis-wg [mailto:isis-wg-bounces@ietf.org] On Behalf Of >>> Naiming Shen (naiming) >>> Sent: Saturday, December 30, 2017 11:59 AM >>> To: Alexander Okonnikov >>> <alexander.okonnikov@gmail.com<mailto:alexander.okonnikov@gmail.com>> >>> Cc: isis-wg@ietf.org<mailto:isis-wg@ietf.org>; Christian Hopps >>> <chopps@chopps.org<mailto:chopps@chopps.org>>; >>> isis-ads@ietf.org<mailto:isis-ads@ietf.org> >>> Subject: Re: [Isis-wg] WG Last Call for >>> draft-ietf-isis-reverse-metric-07 >>> >>> >>> Hi Alex, >>> >>> Ok. We’ll add a bit to the flag (the 2nd bit) of the >>> ‘reverse-metric TLV’, to indicate >>> the originator requesting the inbound direction of the link >>> not to be used and the >>> metric should be raised by the peer to (2^24 - 1) regardless >>> the value of the ‘offset metric’ >>> value in the TLV. >>> >>> thanks. >>> - Naiming >>> >>> On Dec 29, 2017, at 11:46 AM, Alexander Okonnikov >>> <alexander.okonnikov@gmail.com<mailto:alexander.okonnikov@gmail.com>> >>> wrote: >>> >>> Hi Naiming, >>> >>> >>> >>> >>> >>> 29 дек. 2017 г., в 6:10, Naiming Shen (naiming) >>> <naiming@cisco.com<mailto:naiming@cisco.com>> написал(а): >>> >>> >>> Hi Alexander, >>> >>> Thanks for the comments, see more replies inline. >>> >>> >>> >>> >>> >>> On Dec 14, 2017, at 9:24 AM, Alexander Okonnikov >>> <alexander.okonnikov@gmail.com<mailto:alexander.okonnikov@gmail.com>> >>> wrote: >>> >>> Hi authors, >>> >>> >>> I have some comments below regarding the draft: >>> >>> >>> 1) Section 2: "There is currently only two Flag bits defined." >>> Per -07 only one flag is defined. S flag was deprecated since >>> version -06 (implicit signaling of presence of Sub-TLVs is >>> used via "Sub-TLV Len" field non-zero value. Text in the >>> beginning of the chapter 2 about flag S is to be removed as >>> well. >>> >>> NS> will fix. >>> >>> >>> >>> >>> >>> >>> 2) Section 3.1: "In order to ensure that an individual TE link >>> is used as a link of last resort during SPF computation, ..." >>> I guess that you meant regular link rather than TE link. >>> >>> 3) For the same section: Per my understanding, this section >>> assumes that overloaded link will always be considered as >>> last-resort link. I.e. it cannot be excluded from topology (as >>> link with metric 2^24-1), unless originator of the TLV sets >>> appropriate bit in corresponding Link Attributes Sub-TLV (RFC >>> 5029) AND receiving ISs support that Sub-TLV. As alternative >>> it could be done by allowing for originator to specify reverse >>> metric special value 2^24-1 which would indicate to receivers >>> that the link is to be excluded from topology completely >>> rather than used as last resort. If reverse metric value is >>> between 0 - 2^24-2 then link could be used in path >>> calculation. The same rules for TE metric. >>> >>> >>> NS> I don’t see there is much difference between not used or >>> last resort in the use cases we mentioned. >>> also, this metric value is an ‘offset metric’ being added on >>> top of the existing local metric. It would not >>> be always feasible to make the reverse-metric off by one to >>> mean two completely different operations. >>> >>> One use case when unusable link vs last resort one makes sense >>> is for IGP-LDP sync. Let's assume we have two-level IS-IS >>> domain. There are three ISs in the domain: R1 and R2 are L1/L2 >>> ISs, and R3 is L1-only. R1 and R2 are connected to each other >>> via L2 circuit, and R3 is connected to R1 and R2 via L1 >>> circuits. The link between R2 and R3 was broken and now is >>> being restored. While adjacency has not been established on >>> failed link, R3 has inter-area route towards R2's loopback. >>> Once adjacency has been established, but LDP session has not >>> yet, R3 and R2 maximize metric (2^24-2) on corresponding link. >>> But now R2 and R3 have routes to each other as L1 intra-area, >>> though with max metric. Because L1 intra-area route wins, R2 >>> and R3 replace inter-area routes to each other by intra-area >>> ones. As a result, LDP LSPs are blackholed. On the other hand, >>> if two routers mark corresponding link as unusable (with >>> metric 2^24-1), they would use inter-area routes until IGP-LDP >>> sync will be com >> pleted. >>> >>> An IS can make decision on whether to mark link as unusable or >>> as last resort, using the same principle as proposed in RFC >>> 6138. >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> 4) For the same section: The draft says that if originator >>> uses narrow metric-type, it should use value 63 as max-metric. >>> But on receiving reverse metric with such value receivers have >>> no idea whether this is "narrow" max-metric or offset 63 for >>> "wide" metric. I.e. the draft assumes that all ISs use the >>> same type of metric, and using of two metric types at the same >>> time is not covered. May be it would be appropriate to define >>> two Reverse Metric TLVs, like IS Neighbors TLV and Extended IS >>> Reachability TLV. Or to specify new flag to mark type of the >>> reverse metric. >>> >>> >>> NS> to be simple, we have to assume a network is either run >>> wide or narrow. It can not be fixed. The >>> document is trying to be complete to mention the ‘narrow’ >>> case. >>> >>> >>> >>> >>> >>> >>> 5) For the same section: It is not clear for me why DIS should >>> use min(63, (Metric + Reverse Metric)) while composing >>> pseudonode LSP. If DIS is configured for using "wide" >>> metric-type, it will use Extended IS Reachability TLVs for >>> describing its neighbors. Moreover, in this case DIS is not >>> obligated to still insert IS Neighbors TLVs in its Pseudonode >>> LSP (in addition to Extended IS Reachability TLVs) when it is >>> configured for "wide-only" mode. >>> >>> NS> agreed. will remove this, to keep the same goal as above, >>> to be simple. Not to mix them. >>> >>> >>> >>> >>> >>> >>> 6) For the same section: It is not clear for me why in case >>> when TE metric offset is not advertised in Reverse Metric TLV, >>> receiving IS must modify its TE metric by adding IGP reverse >>> metric value. In my mind, it would be straightforward to use >>> follow rule: if originator doesn't include TE metric part then >>> it doesn't wish to overload TE link, but only IGP link. For >>> example, originator advertises Reverse metric TLV as part of >>> IGP-LDP synchronization procedure (section 3.5). It is not >>> reason to impact TE properties (metric in this case) of the >>> link. Hence, originator could advertise Reverse metric TLV >>> without TE metric Sub-TLV, in order to signal that "TE metric >>> is left intact”. >>> >>> NS> sounds resonable. Will change this to say if the sub-TLV >>> of TE is not received, the TE properties will not change >>> by receiving this ‘reverse-metric’ TLV. >>> >>> >>> >>> >>> >>> >>> 7) Section 3.3: The draft is not clear about handling of TE >>> metric by DIS. Usually DIS implementations don't insert TE >>> Sub-TLVs into Extended IS Reachability TLVs in Pseudonode LSP. >>> May be it would be better to add explicit text that: if DIS >>> receives TE metric Sub-TLV in Reverse Metric TLV it should >>> update TE Default Metric Sub-TLV value of corresponding >>> Extended IS Reachability TLV OR insert new one if it was not >>> present there. >>> >>> NS> To me, there is not much difference between DIS and other >>> nodes. Will try to add some words to that. >>> >>> thanks. >>> - Naiming >>> >>> >>> >>> >>> >>> >>> >>> Thanks! >>> >>> >>> 30.11.2017 01:47, Naiming Shen (naiming) пишет: >>> >>> >>> >>> >>> Hi Ketan, >>> >>> thanks for the support and comments. some clarification >>> inline, >>> >>> >>> >>> >>> >>> On Nov 28, 2017, at 11:54 PM, Ketan Talaulikar (ketant) >>> <ketant@cisco.com<mailto:ketant@cisco.com>> wrote: >>> >>> Hello, >>> >>> I support this draft, however would like the following >>> aspect/scenario clarified. >>> >>> Consider the scenario where both the neighbours on a p2p link >>> initiate the reverse metric procedure (i.e. include the TLV in >>> their hellos concurrently). How are implementations supposed >>> to handle this? Normally the choice of metric conveyed via >>> this TLV is based on a particular condition (which need not >>> just be "overload") on the local router which requires the >>> neighbour to use shift to using the reverse metric supplied. >>> So when both neighbours initiate this process, it would be >>> good to have the specification provide a deterministic >>> behaviour since the reverse metric values provided may >>> conflict in certain "non-overload" conditions. If both routers >>> simply accept the value supplied by their neighbour, it may >>> not achieve the original purpose/design of this triggering >>> this mechanism? >>> When you say if both sides initiated this ‘reverse metric’, >>> you implied >>> there is a timing issue with this procedure in the draft. >>> >>> The value of this ‘metric offset’ (or whatever will be called) >>> of this TLV, >>> is just a number. The draft does not say this number is equal >>> to the >>> configured ‘metric’ value plus the received ‘reverse metrc’ >>> value, that >>> would be non-deterministic and both sides would keep going up >>> until it’s >>> overloaded:-) >>> >>> Each side of IS-IS link decides if it needs to send a ‘reverse >>> metric’ over the link, >>> either in link-overloading case, or other cases. It’s a static >>> number, it does not >>> depend on the other side sending a ‘reverse metric’ or not. >>> This both sides >>> sending a ‘reverse-metric’ over a link is equivalent to an >>> operator provisions >>> new metric (say both plus 10 to the old metric) on both sides >>> of the link at >>> the same time, there is no non-determinitic thing in this. >>> >>> thanks. >>> - Naiming >>> >>> >>> >>> >>> >>> Following options come to my mind: >>> a) when this condition is detected, none of the routers >>> actually apply the reverse metric procedure >>> b) when this condition is detected, the router with >>> higher/lower system-id value (or some such tiebreaker) wins >>> and the other withdraws its reverse metric (until then (a) >>> applies) >>> c) some mechanism/rule that is based on the value of metric >>> offset specified perhaps (made harder since the actual metric >>> is not signalled but the offset) which determines the "winner" >>> so the other withdraws their TLV. >>> >>> Since the mechanism is not specific to overload conditions >>> (where this is not an issue), it may be necessary for the >>> specification to clarify this behaviour to ensure >>> interoperability. >>> >>> Thanks, >>> Ketan >>> >>> -----Original Message----- >>> From: Isis-wg [mailto:isis-wg-bounces@ietf.org] On Behalf Of >>> Christian Hopps >>> Sent: 16 November 2017 04:13 >>> To: isis-wg@ietf.org<mailto:isis-wg@ietf.org> >>> Cc: isis-ads@ietf.org<mailto:isis-ads@ietf.org> >>> Subject: [Isis-wg] WG Last Call for >>> draft-ietf-isis-reverse-metric-07 >>> >>> >>> The authors have asked for and we are starting a WG Last Call >>> on >>> >>> https://datatracker.ietf.org/doc/draft-ietf-isis-reverse-metric/ >>> >>> which will last an extended 3 weeks to allow for IETF100. >>> >>> Thanks, >>> Chris. >>> >>> _______________________________________________ >>> Isis-wg mailing list >>> Isis-wg@ietf.org<mailto:Isis-wg@ietf.org> >>> https://www.ietf.org/mailman/listinfo/isis-wg >>> >>> _______________________________________________ >>> Isis-wg mailing list >>> Isis-wg@ietf.org<mailto:Isis-wg@ietf.org> >>> https://www.ietf.org/mailman/listinfo/isis-wg >>> _______________________________________________ >>> Isis-wg mailing list >>> Isis-wg@ietf.org<mailto:Isis-wg@ietf.org> >>> https://www.ietf.org/mailman/listinfo/isis-wg >>> >>> >>> _______________________________________________ >>> Isis-wg mailing list >>> Isis-wg@ietf.org >>> https://www.ietf.org/mailman/listinfo/isis-wg
- [Isis-wg] WG Last Call for draft-ietf-isis-revers… Christian Hopps
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Acee Lindem (acee)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Acee Lindem (acee)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Acee Lindem (acee)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Acee Lindem (acee)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Ketan Talaulikar (ketant)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Alexander Okonnikov
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… t.petch
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Alexander Okonnikov
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Alexander Okonnikov
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Alexander Okonnikov
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Alexander Okonnikov
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… t.petch
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Christian Hopps
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Les Ginsberg (ginsberg)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Alexander Okonnikov
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Alexander Okonnikov
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Alexander Okonnikov
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Christian Hopps
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- Re: [Isis-wg] WG Last Call for draft-ietf-isis-re… Naiming Shen (naiming)
- [Isis-wg] WG Last Call for draft-ietf-isis-revers… Christian Hopps