Re: [manet] draft-ietf-manet-aodvv2-13 review - a couple of big ticket Items

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> On 17 Mar 2016, at 17:25, Lotte Steenbrink <[e-mail]> wrote:
> 
> Hi Thomas, 
> 
>> Am 17.03.2016 um 17:00 schrieb [e-mail] <mailto:[e-mail]>:
>> 
>> Dear all,
>> 
>> Apologies for not having gotten this done sooner - day-job leaving few spare cycles.
>> 
>> I’ve previously offered reviews and comments, and some of those have been addressed in the latest I-D — others have not, but should be. I recall that there was some mail attempting to rebut parts of the review, and I will dig it out and reply to that.
>> 
>> With that being said, I have reviewed the latest version of the document, and full details will be forthcoming. There’re a couple of big-ticket/architectural items that I want to address up front, as I believe that before we have those hammered out, it will be useless to go into details. Note, I do not claim that this is an exhaustive list of “big ticket items”, but that’s as far as I have gotten in thinking this through.
>> 
>> I also bring these up as they are items that have been brought up repeatedly over the past years, but not resolved nor discussed.
>> 
>> Loops
>> Just to bring this out: I share Chris’ worry about conflicting and concurrent statements from the authors on “There are no loops possible” and “We need to fix two situations where loops can occur” and “we are still investigating some loop conditions”
> 
> Just one thing until I can go through your entire review: the conflict was between „There are no loops possible“ and „There were two loops possible and we’ve fixed them.“. I’ve written down the fixes for said loops under the description how they can occur.

On March 1, Perkins wrote:
> Other discussion about routing loops has not identified routing loop problems in the existing specification.  Use of unconfirmed or invalid routes for routing might lead to errors, but that doesn't carry over to produce loops in the route table.

On March 2, Chris wrote:
> My concerns have been that your co-authors have continued to discuss whether looping could occur since you published to the list saying all was well. (An issue to do with multiple unconfirmed routes.) Maybe that’s a problem, maybe it isn’t. But it lacks transparency, because it hasn’t been discussed here.

Which yesterday, March 16, you replied to by saying:
> The loop possibility you’re referring to was a different one than the one discussed by Charlie. We’ve been contacted by researchers who are model checking MANET protocols to see if they permit any unwanted behaviour. They’ve used AODVv2 as a case study for the framework they’ve implemented to do this, and they’ve found the following loop:



Of course, not being privy to non-mane-list-discussions,  all I can go by is public record. Which is that Perkins clearly affirmed (on the list) that there had been looping discussions, but no loop possibilities identified, on March 1, and you wrote March 16 that apparently there was another loop possibility discussed, brought t you by some researchers …