Re: [nemo] WG Last Call on draft-ietf-nemo-terminology

[Chan-Wah Ng <[e-mail]>]

On Mon, 2005-11-21 at 11:47 +0900, Romain KUNTZ wrote:
> Hello Chan-Wah,
> 
> Chan-Wah Ng wrote:
> >>A split NEMO occurs when a single mobile subnet connected to multiple 
> >>Mobile Routers, or multiple mobile subnets interconnected with routers, 
> >>become two or more independant mobile subnets.
> > 
> > It all depends on what is the motivation for the inclusion of the
> > split-NEMO definition.  I thought the motivation was to assist in
> > illustrating the problem of split NEMO as documented in
> > draft-ietf-nemo-multihoming-issues.  If this is indeed the case, then
> > the definition of split-NEMO should define cases only when the problem
> > of split NEMO occurs.
> 
> I agree. So do you see other case than (n,1,1) with the following topology:
> 
> 
>      |    |             |      |
>     MR1  MR2           MR1    MR2
>      |    |      ->     |      |
>    ----------         -----  -----
> 
> (ie multiple MRs attached to the same mobile subnet on their ingress 
> interface, registering the same prefix to the same HA)
> 
> where split NEMO is a problem?
> 

No, I do not at this moment.  Although strictly speaking , all
(n,>=1,>=1) networks will face the same problem, but these can always be
decomposed to multiple (n,1,1)s.

Hence, I would modify the definition of split-NEMO to:

        Split-NEMO refers to case where a mobile network that has
        multiple mobile routers handling the same MNP (or MNPs) becoming
        two or more independent mobile networks.

One can go on to be more specific, such as adding "where the
aforementioned group of mobile routers handling the same MNP(s) are no
longer all residing in the same mobile network".  That may seems messy,
but is more accurate.

The above definition avoids the use of mobile subnet, in case someone in
the future, against all odds, come up with a split-NEMO configuration
that has a LFR in between, the definition still fits :).

/rgds
/cwng