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

["Acee Lindem (acee)" <[e-mail]>]

Hi Hannes, 

On 1/19/17, 11:30 PM, "Hannes Gredler" <[e-mail]> wrote:

>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.

I agree but was just trying to get a better idea of precisely how the
information will be used and whether interface is the right granularity.

Thanks,
Acee 




>
>/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 node¹s RTM
>> capabilities and distribute them to the other nodes is undefined.
>> Further, one of the ways by which an omniscient controller learns a
>> node¹s 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.
>> 
>>  
>> 
>> I¹m sorry but I focused mainly on the OSPF protocol aspects then and
>> didn¹t 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
>>             wouldn¹t always be advertised doesn¹t 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, we¹ve 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].
>> 
>> 
>>                 
>> 
>>                 
>> 
>>                 
>> 
>>                 
>> 
>>              
>> 
>>          
>>