Re: [mpls] Review of draft-ietf-mpls-residence-time-12

[Hannes Gredler <[e-mail]>]

hi les,

we have taken turns long-time ago to advertise non-routing
related information which is only relevant to controllers
(l2bundles comes into mind ;-)).

while it would have been nice to get at least notice that
an IS-IS extension is being worked on (i mean prior to
IANA asking for expert review :-/ ) i see no reason why we
should hold this back. - we can argue perhaps whether it should
be part of GENAPP or ROUTERCAP TLVs, but i cannot see the
sky falling to advertise a non-routing related capability,
that does not change frequently.

/hannes

On 1/19/17 18:24, Les Ginsberg (ginsberg) wrote:
> John –
> 
>  
> 
> For me, this raises the age-old question of when it is/is not
> appropriate to use IGPs for flooding information.
> 
>  
> 
> This is clearly not TE information – you just happen to be using this in
> conjunction with MPLS – but it is a generic capability. I do not see the
> IGPs as the appropriate mechanism to flood generic interface
> capabilities. It also, as Acee has pointed out, results in flooding
> information to all nodes in the domain when only a few care about it.
> 
>  
> 
>    Les
> 
>  
> 
> *From:*John E Drake [mailto:[e-mail]]
> *Sent:* Thursday, January 19, 2017 8:54 AM
> *To:* Acee Lindem (acee); Alexander Vainshtein; Greg Mirsky; Les
> Ginsberg (ginsberg)
> *Cc:* Robert Sparks; [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; Abhay Roy (akr)
> *Subject:* RE: [mpls] Review of draft-ietf-mpls-residence-time-12
> 
>  
> 
> Acee,
> 
>  
> 
> Relying on an omniscient controller is a non-starter in general and in
> particular because the protocol by which it would learn each node’s RTM
> capabilities and distribute them to the other nodes is undefined. 
> Further, one of the ways by which an omniscient controller learns a
> node’s capabilities is by snooping the link/state database.
> 
>  
> 
> Yours Irrespectively,
> 
>  
> 
> John
> 
>  
> 
> *From:*Acee Lindem (acee) [mailto:[e-mail]]
> *Sent:* Thursday, January 19, 2017 11:47 AM
> *To:* John E Drake <[e-mail] <mailto:[e-mail]>>;
> Alexander Vainshtein <[e-mail]
> <mailto:[e-mail]>>; Greg Mirsky
> <[e-mail] <mailto:[e-mail]>>; Les Ginsberg
> (ginsberg) <[e-mail] <mailto:[e-mail]>>
> *Cc:* Robert Sparks <[e-mail]
> <mailto:[e-mail]>>; [e-mail] <mailto:[e-mail]>;
> [e-mail] <mailto:[e-mail]>;
> [e-mail]
> <mailto:[e-mail]>; [e-mail]
> <mailto:[e-mail]>; [e-mail]
> <mailto:[e-mail]>; Abhay Roy (akr) <[e-mail]
> <mailto:[e-mail]>>
> *Subject:* Re: [mpls] Review of draft-ietf-mpls-residence-time-12
> 
>  
> 
> Hi John, 
> 
>  
> 
> *From: *John E Drake <[e-mail] <mailto:[e-mail]>>
> *Date: *Thursday, January 19, 2017 at 10:43 AM
> *To: *Acee Lindem <[e-mail] <mailto:[e-mail]>>, Alexander
> Vainshtein <[e-mail]
> <mailto:[e-mail]>>, Greg Mirsky
> <[e-mail] <mailto:[e-mail]>>, "Les Ginsberg
> (ginsberg)" <[e-mail] <mailto:[e-mail]>>
> *Cc: *Robert Sparks <[e-mail]
> <mailto:[e-mail]>>, "[e-mail] <mailto:[e-mail]>"
> <[e-mail] <mailto:[e-mail]>>, "[e-mail]
> <mailto:[e-mail]>" <[e-mail] <mailto:[e-mail]>>,
> "[e-mail]
> <mailto:[e-mail]>"
> <[e-mail]
> <mailto:[e-mail]>>, "[e-mail]
> <mailto:[e-mail]>" <[e-mail] <mailto:[e-mail]>>,
> "[e-mail] <mailto:[e-mail]>"
> <[e-mail] <mailto:[e-mail]>>, "Abhay Roy (akr)"
> <[e-mail] <mailto:[e-mail]>>
> *Subject: *RE: [mpls] Review of draft-ietf-mpls-residence-time-12
> 
>  
> 
>     Acee,
> 
>      
> 
>     We discussed all of this with you over a year ago and used your
>     guidance in adding the indication of RTM capability to OSPF.
> 
>  
> 
> I’m sorry but I focused mainly on the OSPF protocol aspects then and
> didn’t question the use case. This question came up in the IS-IS WG
> discussions. 
> 
>  
> 
> Thanks,
> 
> Acee
> 
>  
> 
>      
> 
>     Yours Irrespectively,
> 
>      
> 
>     John
> 
>      
> 
>     *From:*Acee Lindem (acee) [mailto:[e-mail]]
>     *Sent:* Thursday, January 19, 2017 11:38 AM
>     *To:* Alexander Vainshtein <[e-mail]
>     <mailto:[e-mail]>>; Greg Mirsky
>     <[e-mail] <mailto:[e-mail]>>; Les Ginsberg
>     (ginsberg) <[e-mail] <mailto:[e-mail]>>
>     *Cc:* Robert Sparks <[e-mail]
>     <mailto:[e-mail]>>; [e-mail]
>     <mailto:[e-mail]>; [e-mail] <mailto:[e-mail]>;
>     [e-mail]
>     <mailto:[e-mail]>; [e-mail]
>     <mailto:[e-mail]>; [e-mail]
>     <mailto:[e-mail]>; Abhay Roy (akr) <[e-mail]
>     <mailto:[e-mail]>>
>     *Subject:* Re: [mpls] Review of draft-ietf-mpls-residence-time-12
> 
>      
> 
>     I guess what we were trying to envision the use case and whether it
>     makes sense for all the nodes in the IGP routing domain to have this
>     information. Would the LSP ingress LSR only need to if the egress
>     LSR supports RTM and it is best effort recording for transit LSRs in
>     the path?  
> 
>      
> 
>     Additionally, if it is needed in the IGPs, should there also be a
>     BGP-LS Link Attribute TLV proposed? 
> 
>      
> 
>     Thanks,
> 
>     Acee 
> 
>      
> 
>     *From: *Alexander Vainshtein <[e-mail]
>     <mailto:[e-mail]>>
>     *Date: *Thursday, January 19, 2017 at 10:15 AM
>     *To: *Greg Mirsky <[e-mail]
>     <mailto:[e-mail]>>, "Les Ginsberg (ginsberg)"
>     <[e-mail] <mailto:[e-mail]>>
>     *Cc: *Acee Lindem <[e-mail] <mailto:[e-mail]>>, Robert
>     Sparks <[e-mail] <mailto:[e-mail]>>,
>     "[e-mail] <mailto:[e-mail]>" <[e-mail]
>     <mailto:[e-mail]>>, "[e-mail]
>     <mailto:[e-mail]>" <[e-mail]
>     <mailto:[e-mail]>>,
>     "[e-mail]
>     <mailto:[e-mail]>"
>     <[e-mail]
>     <mailto:[e-mail]>>,
>     "[e-mail] <mailto:[e-mail]>" <[e-mail]
>     <mailto:[e-mail]>>, "[e-mail]
>     <mailto:[e-mail]>" <[e-mail]
>     <mailto:[e-mail]>>, "Abhay Roy (akr)" <[e-mail]
>     <mailto:[e-mail]>>
>     *Subject: *RE: [mpls] Review of draft-ietf-mpls-residence-time-12
> 
>      
> 
>         Hi all,
> 
>         I concur with Greg: from my POV an interoperable solution should
>         not depend on an omniscient NMS client distributing information
>         about capabilities of each node to each other node.
> 
>          
> 
>          
> 
>         Regards,
> 
>         Sasha
> 
>          
> 
>         Office: [phone]
> 
>         Cell:      [phone]
> 
>         Email:   [e-mail]
>         <mailto:[e-mail]>
> 
>          
> 
>         *From:*Greg Mirsky [mailto:[e-mail]]
>         *Sent:* Thursday, January 19, 2017 6:01 PM
>         *To:* Les Ginsberg (ginsberg) <[e-mail]
>         <mailto:[e-mail]>>
>         *Cc:* Acee Lindem (acee) <[e-mail]
>         <mailto:[e-mail]>>; Robert Sparks <[e-mail]
>         <mailto:[e-mail]>>; [e-mail]
>         <mailto:[e-mail]>; [e-mail]
>         <mailto:[e-mail]>;
>         [e-mail]
>         <mailto:[e-mail]>;
>         [e-mail] <mailto:[e-mail]>; [e-mail]
>         <mailto:[e-mail]>; Abhay Roy (akr) <[e-mail]
>         <mailto:[e-mail]>>
>         *Subject:* Re: [mpls] Review of draft-ietf-mpls-residence-time-12
> 
>          
> 
>         Hi Les,
> 
>         I believe that IGP extensions to advertise RTM capability are
>         required.
> 
>          
> 
>         Regards,
> 
>         Greg
> 
>          
> 
>         On Thu, Jan 19, 2017 at 7:57 AM, Les Ginsberg (ginsberg)
>         <[e-mail] <mailto:[e-mail]>> wrote:
> 
>             Greg –
> 
>              
> 
>             I am having trouble understanding your response.
> 
>             The question we are raising is whether we should extend the
>             IGPs to support advertising RTM capability – an alternative
>             being to retrieve the capability via network management.
> 
>              
> 
>             Saying that the IGP functionality is optional and/or
>             wouldn’t always be advertised doesn’t really answer the
>             question of whether we should or should not define the IGP
>             extensions.
> 
>              
> 
>             Could you respond more directly to this point?
> 
>              
> 
>                Les
> 
>              
> 
>              
> 
>             *From:*Greg Mirsky [mailto:[e-mail]
>             <mailto:[e-mail]>]
>             *Sent:* Thursday, January 19, 2017 7:44 AM
>             *To:* Acee Lindem (acee)
>             *Cc:* Robert Sparks; [e-mail] <mailto:[e-mail]>;
>             [e-mail] <mailto:[e-mail]>;
>             [e-mail]
>             <mailto:[e-mail]>;
>             [e-mail] <mailto:[e-mail]>; Les Ginsberg
>             (ginsberg); [e-mail]
>             <mailto:[e-mail]>; Abhay Roy (akr)
> 
> 
>             *Subject:* Re: [mpls] Review of
>             draft-ietf-mpls-residence-time-12
> 
>              
> 
>             Hi Acee,
> 
>             the draft defines optional functionality. If an operator has
>             no use neither for PTP's Transparent Clock, nor RTM itself
>             as performance metric, then RTM sub-TLV would not be
>             included and thus it would not be flooded. Of course, it be
>             right to reflect RTM capability through YANG data model,
>             thus allowing SDN scenario you've described.
> 
>              
> 
>             Regards,
> 
>             Greg
> 
>              
> 
>             On Wed, Jan 18, 2017 at 2:51 PM, Acee Lindem (acee)
>             <[e-mail] <mailto:[e-mail]>> wrote:
> 
>             Hi Greg, 
> 
>              
> 
>             Although it is a bit late, we’ve had some discussions
>             amongst the IS-IS and OSPF chairs and are wondering whether
>             the interface capability belongs in the IGPs. This will be
>             flooded throughout the entire routing domain – is it really
>             needed on every node or will it the RTM testing be initiated
>             from an omniscient NMS client that would know the
>             capabilities of each node or easily query them using YANG? 
> 
>              
> 
>             Thanks,
> 
>             Acee  
> 
>              
> 
>             *From: *mpls <[e-mail]
>             <mailto:[e-mail]>> on behalf of Greg Mirsky
>             <[e-mail] <mailto:[e-mail]>>
>             *Date: *Wednesday, January 18, 2017 at 1:25 PM
>             *To: *Robert Sparks <[e-mail]
>             <mailto:[e-mail]>>
>             *Cc: *"[e-mail] <mailto:[e-mail]>" <[e-mail]
>             <mailto:[e-mail]>>, "[e-mail]
>             <mailto:[e-mail]>" <[e-mail]
>             <mailto:[e-mail]>>,
>             "[e-mail]
>             <mailto:[e-mail]>"
>             <[e-mail]
>             <mailto:[e-mail]>>,
>             "[e-mail] <mailto:[e-mail]>" <[e-mail]
>             <mailto:[e-mail]>>
>             *Subject: *Re: [mpls] Review of
>             draft-ietf-mpls-residence-time-12
> 
>              
> 
>                 Hi Robert,
> 
>                 thank you for the most expedient review and comments.
>                 I'll make changes in Section 2 per your suggestion.
> 
>                  
> 
>                 Regards,
> 
>                 Greg
> 
>                  
> 
>                 On Wed, Jan 18, 2017 at 10:34 AM, Robert Sparks
>                 <[e-mail] <mailto:[e-mail]>> wrote:
> 
>                 The changes all look good.
> 
>                 I still think you should say something in the document
>                 about what "the time of packet arrival" and
>                 "transmission" means, and call out the point you made
>                 about being careful to not introduce apparent jitter by
>                 not making those measurements consistently. (The
>                 definitions you point to in your earlier mail from
>                 G.8013 don't really help - they just say "time of packet
>                 arrival". Again, the first and last bit are likely to be
>                 several nanoseconds apart so I think it matters. Perhaps
>                 you're saying it doesn't matter as long as each node is
>                 consistent (there will be error in the residence time
>                 measurement, but it will be constant at each node, so
>                 the sum of errors will be constant, and the clocks will
>                 be ok?)
> 
>                 Please look at the new first paragraph of section 2 -
>                 there's a mix of "as case" and "in case" that should be
>                 made consistent. I suspect it would be easiest to simply
>                 say "referred to as using a one-step clock" and
>                 "referred to as using a two-step clock" or similar.
> 
>                 RjS
> 
>                  
> 
>                 On 1/18/17 12:03 PM, Greg Mirsky wrote:
> 
>                     Hi Robert,
> 
>                     Sasha Vainshtein came with elegant idea to address
>                     disconnection between discussion of one-step and
>                     two-step modes that you've pointed out. We've moved
>                     Section 7 as sub-section into Section 2 now.
>                     Attached are updated diff and the proposed new
>                     version -13.
> 
>                      
> 
>                     Regards,
> 
>                     Greg
> 
>                      
> 
>                     On Wed, Jan 18, 2017 at 8:13 AM, Greg Mirsky
>                     <[e-mail]
>                     <mailto:[e-mail]>> wrote:
> 
>                     Hi Robert,
> 
>                     once again, thank you for your thorough review and
>                     the most detailed comments. I've prepared updated
>                     version and would greatly appreciate if you review
>                     the changes and let us know whether your comments
>                     been addressed. Attached are diff and the new version.
> 
>                      
> 
>                     Regards,
> 
>                     Greg
> 
>                      
> 
>                     On Wed, Jan 11, 2017 at 7:48 AM, Robert Sparks
>                     <[e-mail] <mailto:[e-mail]>>
>                     wrote:
> 
>                         Reviewer: Robert Sparks
>                         Review result: Ready with Nits
> 
>                         I am the assigned Gen-ART reviewer for this
>                         draft. The General Area
>                         Review Team (Gen-ART) reviews all IETF documents
>                         being processed
>                         by the IESG for the IETF Chair.  Please treat
>                         these comments just
>                         like any other last call comments.
> 
>                         For more information, please see the FAQ at
>                         <https://trac.ietf.org/trac/gen/wiki/GenArtfaq>.
> 
>                         Document: draft-ietf-mpls-residence-time-12
>                         Reviewer: Robert Sparks
>                         Review Date: 2017-01-10
>                         IETF LC End Date: 2017-01-17
>                         IESG Telechat date: 2017-02-02
> 
>                         Summary: Ready (with nits) for publication as a
>                         Proposed Standard
> 
>                         I have two primary comments. I expect both are
>                         rooted in the authors
>                         and working group knowing what the document
>                         means instead of seeing
>                         what
>                         it says or doesn't say:
> 
>                         1) The document is loose with its use of
>                         'packet', and where TTLs
>                         appear when
>                         they are discussed. It might be helpful to
>                         rephrase the text that
>                         speaks
>                         of RTM packets in terms of RTM messages that are
>                         encoded as G-ACh
>                         messages and
>                         not refer to packets unless you mean the whole
>                         encapsulated packet
>                         with MPLS
>                         header, ACH, and G-ACh message.
> 
>                         2) Since this new mechanic speaks in terms of
>                         fractional nanoseconds,
>                         some
>                         discussion of what trigger-point you intend
>                         people to use for taking
>                         the
>                         precise time of a packet's arrival or departure
>                         seems warranted. (The
>                         first and
>                         last bit of the whole encapsulated packet above
>                         are going to appear at
>                         the
>                         physical layer many nanoseconds apart at OC192
>                         speeds if I've done the
>                         math
>                         right). It may be obvious to the folks
>                         discussing this, but it's not
>                         obvious
>                         from the document.  If it's _not_ obvious and
>                         variation in technique
>                         is
>                         expected, then some discussion about issues that
>                         might arise from
>                         different
>                         implementation choices would be welcome.
> 
>                         The rest of these are editorial nits:
> 
>                         It would help to pull an overview description of
>                         the difference
>                         between
>                         one-step and two-step much earlier in the
>                         document. I suggest in the
>                         overview
>                         in section 2. Otherwise, the reader really has
>                         to jump forward and
>                         read section
>                         7 before section 3's 5th bullet makes any sense.
> 
>                         In section 3, "IANA will be asked" should be
>                         made active. Say "This
>                         document
>                         asks IANA to" and point to the IANA
>                         consideration section. Apply
>                         similar
>                         treatment to the other places where you talk
>                         about future IANA
>                         actions.
> 
>                         There are several places where there are missing
>                         words (typically
>                         articles or
>                         prepositions). You're less likely to end up with
>                         misinterpretations
>                         during the
>                         RFC Editor phase if you provide them before the
>                         document gets that far
>                         in the
>                         process. The spots I found most disruptive were
>                         these (this is not
>                         intended to
>                         be exhaustive):
> 
>                           Section 3: "set 1 according" -> "set to 1
>                         according"
>                           Section 3: "the Table 19 [IEEE..." -> "Table
>                         19 of [IEEE..."
>                           Section 4.2: "Detailed discussion of ... modes
>                         in Section 7."
>                                                 -> "Detailed discussion
>                         of ... modes appears
>                         in Section 7."
>                           Section 10: "most of" -> "most of all"
> 
>                         In Setion 3.1 at "identity of the source port",
>                         please point into the
>                         document
>                         that defines this identity and its
>                         representation. I suspect this is a
>                         pointer
>                         into a specific section in IEEE.1588.2008].
> 
> 
>                      
> 
>                      
> 
>                  
> 
>                  
> 
>              
> 
>          
>