[DNA] Re: Route vs Advertise

[Erik Nordmark <erik.nordmark@sun.com>]

Sathya Narayanan wrote:
> Erik -
> 
> It was my understanding that, a host can choose a prefix advertised by
> R1 for its address configuration and use R2 as the default router
> through which it sends is packets; i.e. advertising a prefix doesn't
> mean the router is the only one that can route it.

Your understanding is correct.

Should we move the SEND discussion/clarification to the SEND list until 
we have an answer?

    Erik

> In SEND, 3971, section 7.3:
> 
> Constrained
> 
>       If the network operator wants to constrain which routers are
>       allowed to route particular subnet prefixes, routers should be
>       configured with certificates having subnet prefixes listed in the
>       prefix extension.  These routers SHOULD advertise the subnet
>       prefixes that they are certified to route, or a subset thereof.
> 
> ....
> 
>    Nodes SHOULD use one of the certified subnet prefixes for stateless
>    autoconfiguration.  If none of the advertised subnet prefixes match,
>    the host SHOULD use a different advertising router as its default
>    router, if one is available.
> 
> 
> This text seems to imply that routers advertising a prefix means they
> are the ones allowed to route it.
> Am I missing something?
> 
> thanks,
> Sathya