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

[Jonathan Hui <[e-mail]>]

On Nov 17, 2009, at 9:20 AM, Pascal Thubert (pthubert) wrote:

> When you run the MANEMO trilogy (tree discovery, nina (DAO) and RRH
> (source route)), you see the source route RH2/4 grow upon movement and
> quickly shrink again as the NINA (DAO) states are reestablished.
> When things are stable you only see as many entries as non DAO capable
> nodes along the path. In my case, the source route is done on a MIP/ 
> NEMO
> tunnel, so the RH states are stored in eth binding cache on the home
> agent. But we could store that at the root with exactly the same
> process.
> I can demo that next time we meet if you wish.
>
> http://tools.ietf.org/html/draft-thubert-nemo-reverse-routing-header
> details the RRH, since there is not LSRR in IPv6.
>
> Note that in our case, the information in the header should be locally
> significant, like a label.

Here lies the disconnect.  The real benefit of storing state among  
nodes within the network is to reduce the size of the source route  
header not some attempt to support point-to-point traffic.  If you buy  
that, then the mechanism to establish such state could be much better  
than what's currently defined in the draft.  In particular, there are  
some interesting things we could achieve if we start treating next-hop  
information using locally significant labels rather than globally  
significant IP addresses, as you suggested.  But if done properly, I  
think we can specify such a mechanism as an optimization to basic  
source-route/record-route.

--
Jonathan Hui