Re: [Roll] updating DAO caches (was Re: Something to ADD)

[Richard Kelsey <richard.kelsey at ember.com>]

> From: JP Vasseur <jvasseur at cisco.com>
> Date: Thu, 19 Nov 2009 11:36:49 +0100
>
> On Nov 17, 2009, at 5:38 PM, Jonathan Hui wrote:
>
> > I'll have to admit that I'm not yet convinced of the benefits in  
> > storing DAO state as it currently exists in the draft.  [...]
> > 
> I do agree with the first statement but not with the second paragraph.  
> I do see several deployment cases where no storing DAO would lead to  
> extremely sub-optimal paths and even more importantly traffic  
> congestion when getting closer to the root of course. 

Can you share these cases with us?  I agree with Jonathan
that storing DAO states will typically not provide much
improvement in P2P routing.

> I do see several deployment cases where no storing DAO would lead to  
> extremely sub-optimal paths and even more importantly traffic  
> congestion when getting closer to the root of course. This is true  
> with several networks where the amount of P2P traffic may ned up being  
> not so negligible. The beauty with the current spec is that it allows  
> both deployment models.

It claims to allow both, but fails to actually do so.  That
is the point of the example that I gave and the reason I
keep going on about this.  While the draft says that
intermediate nodes can cache DAOs, it doesn't say how those
caches are updated after a node changes parents.  And
however this is done, we need to avoid the cost of sending
cache updates in the absense of any actual caches.

                                 -Richard Kelsey