Re: 3gpp-analysis document and automatic tunneling

[Pekka Savola <pekkas@netcore.fi>]

On Thu, 29 May 2003, Fred Templin wrote:
> >On Thu, 29 May 2003, Fred Templin wrote:
> >  
> >
> >>>The client is
> >>>in different admin domain as the router
> >>>
> >>>      
> >>>
> >>No. The client gets an RA from the router that contains a non-zero
> >>router lifetime and adds it to the default router list. The client is in
> >>the same admin domain as the router.
> >>    
> >>
> >
> >No.  AFAICS, the router belongs to the 3GPP operator.  The client belongs 
> >to the 3GPP user (user device).  Right?  These are different entities.  
> >Whether RA is used makes no difference.
>
> OK, but there is no difference between this and the model in which the
> GGSN is serving the mobile a native IPv6 PDP context (i.e., the GGSN
> belongs to the 3GPP operator and the client belongs to the 3GPP user.)

Careful: there could be a lot of difference; that is not the original 
ISATAP model.
 
> >>>(tradeoffs of this might be
> >>>manageable), as is in a different admin domain as all the other clients
> >>>(which would also appear to be on the same link).
> >>>
> >>>      
> >>>
> >>All the other clients would also be on the same link as the router. 
> >>    
> >>
> >
> >But also on the same link as other clients in the same 3GPP operator (or
> >maybe the particular GGSN), right?  In any case, it's *NOT* a 
> >point-to-point link between the router and one client, right?
>
> No - it's a multiaccess link just like any other multiaccess link used 
> for IPv6.

Thanks for confirmation.  (It isn't 100% clear what you refer to with
"No", but I'm assuming the latter sentence.)

So, other clients are reachable on the same multiccess link, using
link-local addresses.  That seems pretty significant to me.

All in all, it seems ISATAP is applied in a scenario which it hasn't been
originally designed for, but consideration to the differences in scenarios
are overlooked.

-- 
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings