Re: Poll to adopt initial milestones for the new L3VPN charter

[Thomas Morin <[e-mail]>]

  Hi Eric,

Eric Rosen:
> Thomas Morin:
>> There are absolutely no technical reasons to couple acceptance of the
>> Wildcard and the Extranet documents with either using PE-PE PIM in the
>> absence of MI-PMSI or a new document on using Bidir P-Tunnels.
> [...] I think the real decision to be made is whether the WG really wants to finish
> the work and tie up all the loose ends, or whether the WG wants to continue
> its dormancy and wait to see what gets implemented and deployed ("rough
> consensus and running code").

I don't think you really answered the question I asked, but based on 
your previous emails, I will still try to interpret your answer as a 
reply addressing my question : are you implying that if, beyond 
"Extranet mVPN" and "Wildcard S-PMSI", we do not also adopt some 
milestone on "bidir P-tunnel" and "PIM without an MI-PMSI", then we 
would not "tie up all loose ends" ?

If, so let me disagree, and try to be a bit more nuanced than 
categorizing each item as being a "loose end" or not :
- Extranet mVPN: this is a requirement of RFC4834, and the mVPN base 
specs do not document how this can be done, (i.e. can be seen as a 
"loose end")
- Wildcard S-PMSI: there are two aspects to this subject, on the one 
hand it is an improvement on how S-PMSI bindings are advertised, on the 
other hand it is a key building block of the "PIM over MS-PMSI" approach 
you propose  (ie. *not* a "loose end")
- mVPN fast-failover: targets improving convergence times for mVPN PE 
failures (i.e. targets an "improvement")
- bidir P-tunnels: although the precise subject may not be fully defined 
yet, it seems to be (a) can be a possible P-tunnel scaling improvement 
in the general case but that the base specs may not fully cover (that 
part is in the gray zone between a "loose end" and an "improvement"), 
and (b) something at the core the core of the "PIM over MS-PMSI" 
approach (/that/ part is *not* a "loose end", but totally in the 
category of what targets an "improvement")
- PIM without an MI-PMSI: based on the claims of your draft 
corresponding to this subject, it seems clear that this proposal targets 
an "improvement" of the number of P-tunnel states (i.e. not a "loose end")

It seems to me that:
* fixing "loose ends" should certainly be part of the work the working 
group should tackle (and as such, it makes sense to make Extranet mVPN a 
milestone)
* we shall not sleep and wait for extensive feedback on all deployment 
variants to decide to work on improvements; if we do so, we'll be 3 or 5 
years too late when some operator wants to deploy such an improvements; 
we should instead anticipate, but "anticipating" does not mean that each 
proposed/claimed improvement needs to become a milestone, or a standard 
track working group document, or even become a working group document at 
all; it does not mean either that these statuses have to be decided all 
at once today : this can very much be decided on a case by case basis 
(...this is what is done most of the time in the IETF !!)
* if there is a need to make the working group charter more explicit, 
then we can certainly adopt milestones related to stuff that people seem 
to agree they are valid subjects (that includes the "Wildcard S-PMSI" idea)

Said differently, I think that the milestones in Ben Niven-Jenkins' 
"Poll to adopt initial milestones for the new L3VPN charter" form a good 
set of milestones.

-Thomas