Hi Peter, 

On 1/30/20, 12:25 PM, "Peter Psenak" <ppse...@cisco.com> wrote:

    Hi Acee,
    
    On 30/01/2020 18:12, Acee Lindem (acee) wrote:
    > Hi Peter,
    > 
    > On 1/30/20, 11:36 AM, "Peter Psenak" <ppse...@cisco.com> wrote:
    > 
    >      Hi Acee,
    >      
    >      On 30/01/2020 17:11, Acee Lindem (acee) wrote:
    >      > Hi Ketan,
    >      >
    >      > In that case, it doesn’t make sense to include it in the End.X
    >      > advertisement since you need to look it up to check it anyway. I 
don’t
    >      > see any benefit here.
    >      The benefit is to make sure that the END.X SID that was configured 
for
    >      the algo X is covered by the locator that has the same algo.
    >      
    >      If you do not advertise the algo with END.X SID, you have no way of
    >      checking that on rcv side.
    > 
    > Ok - so it is to verify that algorithm for the adjacency matches that 
algorithm for the longest match locator - which may be advertised by a 
>different OSPFv3 router. Correct? 
    
    yes.
    
    
    >I guess I don't see why the algorithm for the END.X SID just isn't defined 
as the algorithm from the longest match locator. That way, everyone in >the 
area would use the same one and there would be less that could go wrong. What 
am I missing?
    
    locators may change over time. During the reconfiguration a END.X SID 
    may wrongly be associated with the incorrect locator from a different algo.
    
    Also if for some reason the right locator is not advertised (due to a 
    bug on the originator), END.X SID traffic may be sent using a wrong 
    algo. We wanted to avoid it as that can be seen as a security issue.

Ok - makes sense. It would be good to capture these reasons in the along with 
the test for ignoring END.X SIDs that have conflicting algorithms with their 
longest matching locator. 
    
    thanks,
    Peter
    
    
    
    > 
    > Thanks,
    > Acee
    > 
    >      
    >      thanks,
    >      Peter
    >      
    >      >
    >      > Thanks,
    >      >
    >      > Acee
    >      >
    >      > *From: *"Ketan Talaulikar (ketant)" <ket...@cisco.com>
    >      > *Date: *Thursday, January 30, 2020 at 11:06 AM
    >      > *To: *Acee Lindem <a...@cisco.com>, "li_zhenqi...@hotmail.com"
    >      > <li_zhenqi...@hotmail.com>, Christian Hopps <cho...@chopps.org>, 
lsr
    >      > <lsr@ietf.org>
    >      > *Cc: *draft-li-lsr-ospfv3-srv6-extensions
    >      > <draft-li-lsr-ospfv3-srv6-extensi...@ietf.org>, lsr-ads 
<lsr-...@ietf.org>
    >      > *Subject: *RE: [Lsr] WG Adoption Call for
    >      > draft-li-lsr-ospfv3-srv6-extensions
    >      >
    >      > Hi Acee/Zhen,
    >      >
    >      > The sec 8 of the draft has the following text which specifies the
    >      > handling of this condition.
    >      >
    >      >     All End.X SIDs MUST be subsumed by the subnet of a Locator 
with the
    >      >
    >      >     matching algorithm which is advertised by the same node in an 
SRv6
    >      >
    >      >     Locator TLV.  End.X SIDs which do not meet this requirement 
MUST be
    >      >
    >      >     ignored.
    >      >
    >      > Thanks,
    >      >
    >      > Ketan
    >      >
    >      > *From:* Acee Lindem (acee) <a...@cisco.com>
    >      > *Sent:* 30 January 2020 21:01
    >      > *To:* li_zhenqi...@hotmail.com; Ketan Talaulikar (ketant)
    >      > <ket...@cisco.com>; Christian Hopps <cho...@chopps.org>; lsr 
<lsr@ietf.org>
    >      > *Cc:* draft-li-lsr-ospfv3-srv6-extensions
    >      > <draft-li-lsr-ospfv3-srv6-extensi...@ietf.org>; lsr-ads 
<lsr-...@ietf.org>
    >      > *Subject:* Re: [Lsr] WG Adoption Call for
    >      > draft-li-lsr-ospfv3-srv6-extensions
    >      >
    >      > Hi Ketan, Zhen,
    >      >
    >      > What happens if there an algorithm conflict between the Adjacency 
END.X
    >      > SID and the longest match Locator SID? Either one has to take 
precedence
    >      > or this is an error condition. In either case, it needs to be 
documented.
    >      >
    >      > Thanks,
    >      >
    >      > Acee
    >      >
    >      > *From: *"li_zhenqi...@hotmail.com 
<mailto:li_zhenqi...@hotmail.com>"
    >      > <li_zhenqi...@hotmail.com <mailto:li_zhenqi...@hotmail.com>>
    >      > *Date: *Thursday, January 30, 2020 at 10:20 AM
    >      > *To: *"Ketan Talaulikar (ketant)" <ket...@cisco.com
    >      > <mailto:ket...@cisco.com>>, Christian Hopps <cho...@chopps.org
    >      > <mailto:cho...@chopps.org>>, lsr <lsr@ietf.org 
<mailto:lsr@ietf.org>>
    >      > *Cc: *draft-li-lsr-ospfv3-srv6-extensions
    >      > <draft-li-lsr-ospfv3-srv6-extensi...@ietf.org
    >      > <mailto:draft-li-lsr-ospfv3-srv6-extensi...@ietf.org>>, lsr-ads
    >      > <lsr-...@ietf.org <mailto:lsr-...@ietf.org>>, Christian Hopps
    >      > <cho...@chopps.org <mailto:cho...@chopps.org>>, Acee Lindem
    >      > <a...@cisco.com <mailto:a...@cisco.com>>
    >      > *Subject: *Re: RE: [Lsr] WG Adoption Call for
    >      > draft-li-lsr-ospfv3-srv6-extensions
    >      >
    >      > For the third concern, I think it is better to list the 
considerations
    >      > behind the format design of the TLVs to help readers understand 
them
    >      > better. For the specification behavior you mention, this doc SHOULD
    >      > specify it explicitly.
    >      >
    >      > By the way, what a router should do when it receives END.X SID
    >      > containing algorithm that is different from the one carried in the
    >      > convering locator?
    >      >
    >      > Best Regards,
    >      >
    >      > Zhenqiang Li
    >      >
    >      > 
------------------------------------------------------------------------
    >      >
    >      > li_zhenqi...@hotmail.com <mailto:li_zhenqi...@hotmail.com>
    >      >
    >      >     *From:*Ketan Talaulikar (ketant) <mailto:ket...@cisco.com>
    >      >
    >      >     *Date:* 2020-01-30 16:44
    >      >
    >      >     *To:*li_zhenqi...@hotmail.com 
<mailto:li_zhenqi...@hotmail.com>;
    >      >     Christian Hopps <mailto:cho...@chopps.org>; lsr 
<mailto:lsr@ietf.org>
    >      >
    >      >     *CC:*draft-li-lsr-ospfv3-srv6-extensions
    >      >     <mailto:draft-li-lsr-ospfv3-srv6-extensi...@ietf.org>; lsr-ads
    >      >     <mailto:lsr-...@ietf.org>; Christian Hopps
    >      >     <mailto:cho...@chopps.org>; Acee Lindem (acee) 
<mailto:a...@cisco.com>
    >      >
    >      >     *Subject:* RE: RE: [Lsr] WG Adoption Call for
    >      >     draft-li-lsr-ospfv3-srv6-extensions
    >      >
    >      >     Please check inline again.
    >      >
    >      >     *From:* li_zhenqi...@hotmail.com 
<mailto:li_zhenqi...@hotmail.com>
    >      >     <li_zhenqi...@hotmail.com <mailto:li_zhenqi...@hotmail.com>>
    >      >     *Sent:* 30 January 2020 13:46
    >      >     *To:* Ketan Talaulikar (ketant) <ket...@cisco.com
    >      >     <mailto:ket...@cisco.com>>; Christian Hopps <cho...@chopps.org
    >      >     <mailto:cho...@chopps.org>>; lsr <lsr@ietf.org 
<mailto:lsr@ietf.org>>
    >      >     *Cc:* draft-li-lsr-ospfv3-srv6-extensions
    >      >     <draft-li-lsr-ospfv3-srv6-extensi...@ietf.org
    >      >     <mailto:draft-li-lsr-ospfv3-srv6-extensi...@ietf.org>>; lsr-ads
    >      >     <lsr-...@ietf.org <mailto:lsr-...@ietf.org>>; Christian Hopps
    >      >     <cho...@chopps.org <mailto:cho...@chopps.org>>; Acee Lindem 
(acee)
    >      >     <a...@cisco.com <mailto:a...@cisco.com>>
    >      >     *Subject:* Re: RE: [Lsr] WG Adoption Call for
    >      >     draft-li-lsr-ospfv3-srv6-extensions
    >      >
    >      >     Thank you KT for your quick response. Please see my reply 
begins
    >      >     with [ZQ].
    >      >
    >      >     Best Regards,
    >      >
    >      >     Zhenqiang Li
    >      >
    >      >     
------------------------------------------------------------------------
    >      >
    >      >     li_zhenqi...@hotmail.com <mailto:li_zhenqi...@hotmail.com>
    >      >
    >      >         *From:*Ketan Talaulikar (ketant) <mailto:ket...@cisco.com>
    >      >
    >      >         *Date:* 2020-01-30 13:42
    >      >
    >      >         *To:*li_zhenqi...@hotmail.com 
<mailto:li_zhenqi...@hotmail.com>;
    >      >         Christian Hopps <mailto:cho...@chopps.org>; lsr
    >      >         <mailto:lsr@ietf.org>
    >      >
    >      >         *CC:*draft-li-lsr-ospfv3-srv6-extensions
    >      >         <mailto:draft-li-lsr-ospfv3-srv6-extensi...@ietf.org>; 
lsr-ads
    >      >         <mailto:lsr-...@ietf.org>; Christian Hopps
    >      >         <mailto:cho...@chopps.org>; Acee Lindem (acee)
    >      >         <mailto:a...@cisco.com>
    >      >
    >      >         *Subject:* RE: [Lsr] WG Adoption Call for
    >      >         draft-li-lsr-ospfv3-srv6-extensions
    >      >
    >      >         Hello Zhenqiang Li,
    >      >
    >      >         Thanks for your review and comments. Please check inline 
below.
    >      >
    >      >         *From:*li_zhenqi...@hotmail.com
    >      >         <mailto:li_zhenqi...@hotmail.com> <li_zhenqi...@hotmail.com
    >      >         <mailto:li_zhenqi...@hotmail.com>>
    >      >         *Sent:* 30 January 2020 08:46
    >      >         *To:* Christian Hopps <cho...@chopps.org
    >      >         <mailto:cho...@chopps.org>>; lsr <lsr@ietf.org
    >      >         <mailto:lsr@ietf.org>>
    >      >         *Cc:* draft-li-lsr-ospfv3-srv6-extensions
    >      >         <draft-li-lsr-ospfv3-srv6-extensi...@ietf.org
    >      >         <mailto:draft-li-lsr-ospfv3-srv6-extensi...@ietf.org>>; 
lsr-ads
    >      >         <lsr-...@ietf.org <mailto:lsr-...@ietf.org>>; Christian 
Hopps
    >      >         <cho...@chopps.org <mailto:cho...@chopps.org>>; Acee Lindem
    >      >         (acee) <a...@cisco.com <mailto:a...@cisco.com>>
    >      >         *Subject:* Re: [Lsr] WG Adoption Call for
    >      >         draft-li-lsr-ospfv3-srv6-extensions
    >      >
    >      >         support the adoption with the following comments.
    >      >
    >      >         1. What does SRH stack mean in section 4.2? AS specified in
    >      >         RFC8200 and draft-ietf-6man-segment-routing-header, only 
one SRH
    >      >         can be presented in one IPv6 header.
    >      >
    >      >         */[KT] Thanks for catching this error and will fix as 
below:/*
    >      >
    >      >         *//*
    >      >
    >      >         */OLD: /*The Maximum End Pop MSD Type specifies the 
maximum number of SIDs in
    >      >
    >      >             the top SRH in an SRH stack to which the router can 
apply
    >      >         Penultimate
    >      >
    >      >             Segment Pop (PSP) or Ultimate Segment Pop (USP)
    >      >
    >      >         *//*
    >      >
    >      >         */NEW:/*The Maximum End Pop MSD Type specifies the maximum 
number of SIDs in
    >      >
    >      >             the SRH for which the router can apply Penultimate
    >      >
    >      >             Segment Pop (PSP) or Ultimate Segment Pop (USP)
    >      >
    >      >
    >      >
    >      >
    >      >         [ZQ] Fine.
    >      >
    >      >         2. The abbreviations used in this draft should be listed 
in a
    >      >         seperated section or point out where they are defined.
    >      >
    >      >         */[KT] We’ve followed the convention of expanding on first 
use
    >      >         as also providing reference where necessary. Please do let 
know
    >      >         if we’ve missed doing so anywhere./*
    >      >
    >      >         [ZQ] Some examples: SPF computation in secction 5,  TBD in
    >      >         section 2.
    >      >
    >      >         */[KT] Will expand SPF and some other such on first use 
:-). The
    >      >         TBD (to be decided) is for use until the code point are
    >      >         allocated by IANA./*
    >      >
    >      >         3. Algorithm field is defined for End.x SID to carry the
    >      >         algorithm the end.x sid associates. But no algorithm field 
is
    >      >         defined for End SID in section 7. May I know the reason?
    >      >
    >      >         */[KT] The SRv6 Locator TLV that is the parent of the SRv6 
End
    >      >         SID Sub-TLV carries the algorithm and hence there is no 
need to
    >      >         repeat in the Sub-TLV. This is not the case for SRv6 End.X 
SID
    >      >         Sub-TLV and hence it has the algorithm field./*
    >      >
    >      >         */
    >      >
    >      >
    >      >         /*
    >      >
    >      >         [ZQ] Make sense but still a little bit weird. Since any SID
    >      >         belongs to a locator, or it is not routable, the algorithm 
field
    >      >         in the end.x sid is not needed, end.x sid associates the
    >      >         algorithm carried in the corresponding locator tlv.
    >      >
    >      >         */[KT] Having an algorithm field advertised with the End.X 
SID
    >      >         makes it easier for implementation to find the algorithm
    >      >         specific End.X SID without making the longest prefix match 
on
    >      >         all locators advertised by the node to find the algorithm 
to
    >      >         which the SID belongs. It also makes it possible to verify 
that
    >      >         the algorithm associated with the End.X SID matches that 
of the
    >      >         covering Locator when the link advertisement with End.X 
SID is
    >      >         received. /*
    >      >
    >      >         *//*
    >      >
    >      >         */Thanks,/*
    >      >
    >      >         */Ketan/*
    >      >
    >      >         *//*
    >      >
    >      >         */Thanks,/*
    >      >
    >      >         */Ketan/*
    >      >
    >      >         Best Regards,
    >      >
    >      >         Zhenqiang Li
    >      >
    >      >         
------------------------------------------------------------------------
    >      >
    >      >         li_zhenqi...@hotmail.com <mailto:li_zhenqi...@hotmail.com>
    >      >
    >      >             *From:*Christian Hopps <mailto:cho...@chopps.org>
    >      >
    >      >             *Date:* 2020-01-24 04:24
    >      >
    >      >             *To:*lsr <mailto:lsr@ietf.org>
    >      >
    >      >             *CC:*draft-li-lsr-ospfv3-srv6-extensions
    >      >             <mailto:draft-li-lsr-ospfv3-srv6-extensi...@ietf.org>;
    >      >             lsr-ads <mailto:lsr-...@ietf.org>; Christian Hopps
    >      >             <mailto:cho...@chopps.org>; Acee Lindem \(acee\)
    >      >             <mailto:a...@cisco.com>
    >      >
    >      >             *Subject:* [Lsr] WG Adoption Call for
    >      >             draft-li-lsr-ospfv3-srv6-extensions
    >      >
    >      >             Hi LSR WG and Draft Authors,
    >      >
    >      >             The authors originally requested adoption back @ 105;
    >      >             however, some comments were received and new version 
was
    >      >             produced. Moving forward...
    >      >
    >      >             This begins a 2 week WG adoption poll for the 
following draft:
    >      >
    >      >             
https://datatracker.ietf.org/doc/draft-li-lsr-ospfv3-srv6-extensions/
    >      >
    >      >             Please indicate your support or objection by Feb 6, 
2020.
    >      >
    >      >             Authors, please respond indicating whether you are 
aware of
    >      >             any IPR that applies to this draft.
    >      >
    >      >             Thanks,
    >      >
    >      >             Chris & Acee.
    >      >
    >      >             _______________________________________________
    >      >
    >      >             Lsr mailing list
    >      >
    >      >             Lsr@ietf.org <mailto:Lsr@ietf.org>
    >      >
    >      >             https://www.ietf.org/mailman/listinfo/lsr
    >      >
    >      
    >      
    > 
    > 
    > 
    
    

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