Re: [DNA] [Issue X] LinkID v.s. Landmark Prefix

[JinHyeock Choi <jinchoe@gmail.com>]

Dear Erik

> > If we need to have the similar confidence in determining the link change
> > with
> > graceful prefix addition/deletion, we need similar techniques for all of
> > the
> > prefixes on the link incase of Landmark/CompleteRA.
> 
> Syam,
> You keep making this statement, but I think it is factually incorrect.
> See my other email responding to JinHyoeck.

In linkid scheme, a prefix addition or deletion would not 
cause an incorrect decision, whereas there is such a 
possibility for Landmark/ CompleteRA. 

Allow me an example. 

Assume a link with a router R and host H. 
R advertises Prefix1. 

R1 happens to stop advertising Prefix1 and 
start advertising a new prefix Prefix2. 

R announces it by sending an RA but H 
doesn't receive it. 

Then next time H receives CompleteRA with
Prefix2, it will falsely assume a link change.   

Linkid scheme deal with such a temporary flapping by adopting 
extra techniques such as "Linkid Prefix List" or "LEAST_VALID_LIFETIME". 

I don't know how Landmark/ CompleteRA can make a correct decision
under flapping without such an extra techniques. 

Thanks in advance for your kind consideration. 

Best Regards

JinHyeock